Thuyết Tương Đối Hẹp Và Rộng Của Albert Einstein

["\u0111\u00e3\tti\u1ebfp\tthu\t\u0111\u01b0\u1ee3c. M\u1ed9t\ttr\u01b0\u1eddng\th\u1ee3p\tkh\u00e1c\tc\u1ee7a\ts\u1ef1\ttr\u00f9ng\th\u1ee3p\ts\u00e2u\tr\u1ed9ng\tc\u1ee7a\tc\u00e1c\th\u1ec7\tqu\u1ea3 l\u00e0\tc\u01a1\th\u1ecdc\tNewton\tm\u1ed9t\tm\u1eb7t,\tv\u00e0\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng\tm\u1eb7t\tkh\u00e1c.\tS\u1ef1 tr\u00f9ng\t h\u1ee3p\t n\u00e0y\t \u0111\u1ea1t\t t\u1edbi\t m\u1ee9c\t \u0111\u1ed9\t r\u1ed9ng\t cho\t \u0111\u1ebfn\t nay\t ng\u01b0\u1eddi\t ta\t ch\u1ec9\t c\u00f3 th\u1ec3\tt\u00ecm\tth\u1ea5y\tm\u1ed9t\ts\u1ed1\t\u00edt\th\u1ec7\tlu\u1eadn\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\tki\u1ec3m\tch\u1ee9ng\t\u0111\u01b0\u1ee3c\tb\u1eb1ng th\u1ef1c\tnghi\u1ec7m\tc\u1ee7a\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng\tm\u00e0\tv\u1eadt\tl\u00fd\tti\u1ec1n-t\u01b0\u01a1ng-\u0111\u1ed1i kh\u00f4ng\tth\u1ec3\tv\u1edbi\tt\u1edbi\t\u0111\u01b0\u1ee3c;\t\u0111i\u1ec1u\tn\u00e0y,\tm\u1eb7c\td\u00f9\tt\u00ednh\td\u1ecb\tbi\u1ec7t\ts\u00e2u\ts\u1eafc\tc\u1ee7a c\u00e1c\tti\u00ean\t\u0111\u1ec1\tc\u1ee7a\thai\tl\u00fd\tthuy\u1ebft.\tSau\t\u0111\u00e2y\tch\u00fang\tta\tmu\u1ed1n\txem\tx\u00e9t\tc\u00e1c h\u1ec7\t lu\u1eadn\t quan\t tr\u1ecdng\t n\u00e0y\t m\u1ed9t\t l\u1ea7n\t n\u1eefa,\t v\u00e0\t th\u1ea3o\t lu\u1eadn\t c\u00e1c\t kinh nghi\u1ec7m\tli\u00ean\tquan\t\u0111\u00e3\tthu\tth\u1eadp\t\u0111\u01b0\u1ee3c\t\u0111\u1ebfn\tnay. A.\tCHUY\u1ec2N\t\u0110\u1ed8NG\tC\u1ee6A\t\u0110I\u1ec2M\tC\u1eacN\tNH\u1eacT\tC\u1ee6A\tSAO\tTH\u1ee6Y Theo\t c\u01a1\t h\u1ecdc\t Newton\t v\u00e0\t \u0111\u1ecbnh\t lu\u1eadt\t h\u1ea5p\t d\u1eabn\t Newton,\t m\u1ed9t\t h\u00e0nh tinh\tquay\tquanh\tm\u1eb7t\ttr\u1eddi\ts\u1ebd\tv\u1ebd\tl\u00ean\tm\u1ed9t\tqu\u1ef9\t\u0111\u1ea1o\tellip\tquanh\tm\u1eb7t tr\u1eddi,\thay\tch\u00ednh\tx\u00e1c\th\u01a1n,\tquanh\ttr\u1ecdng\tt\u00e2m\tchung\tc\u1ee7a\tm\u1eb7t\ttr\u1eddi\tv\u00e0 h\u00e0nh\ttinh.\tTrong\tm\u1ed9t\th\u1ec7\tth\u1ed1ng\tnh\u01b0\tth\u1ebf,\tm\u1eb7t\ttr\u1eddi\thay\ttr\u1ecdng\tt\u00e2m chung\t n\u1eb1m\t t\u1ea1i\t m\u1ed9t\t ti\u00eau\t \u0111i\u1ec3m\t c\u1ee7a\t qu\u1ef9\t \u0111\u1ea1o\t ellip,\t sao\t cho\t trong m\u1ed9t\tn\u0103m-h\u00e0nh-tinh\tkho\u1ea3ng\tc\u00e1ch\tn\u1ed1i\tli\u1ec1n\tm\u1eb7t\ttr\u1eddi\tv\u00e0\th\u00e0nh\ttinh t\u0103ng\tt\u1eeb\tm\u1ed9t\ttr\u1ecb\ts\u1ed1\tc\u1ef1c\tti\u1ec3u\t\u0111\u1ebfn\ttr\u1ecb\ts\u1ed1\tc\u1ef1c\t\u0111\u1ea1i\tr\u1ed3i\tsau\t\u0111\u00f3\ttr\u1edf\tv\u1ec1\tc\u1ef1c ti\u1ec3u\t l\u1ea1i.\t N\u1ebfu\t thay\t \u0111\u1ecbnh\t lu\u1eadt\t h\u1ea5p\t d\u1eabn\t Newton\t b\u1eb1ng\t m\u1ed9t\t \u0111\u1ecbnh\t lu\u1eadt h\u1ea5p\td\u1eabn\tc\u00f3\tph\u1ea7n\tkh\u00e1c\t\u0111i,\tng\u01b0\u1eddi\tta\ts\u1ebd\tt\u00ecm\tth\u1ea5y,\ttheo\t\u0111\u1ecbnh\tlu\u1eadt\tm\u1edbi n\u00e0y,\tchuy\u1ec3n\t\u0111\u1ed9ng\tv\u1eabn\tdi\u1ec5n\tra\tv\u1edbi\tt\u00ednh\tch\u1ea5t\tkho\u1ea3ng\tc\u00e1ch\tm\u1eb7t\ttr\u1eddi -\t h\u00e0nh\t tinh\t bi\u1ebfn\t thi\u00ean\t th\u0103ng\t gi\u1ea3m;\t nh\u01b0ng\t sau\t m\u1ed9t\t chu\t k\u1ef3\t [t\u1eeb \u0111i\u1ec3m\t c\u1eadn\t nh\u1eadt\t (\u0111i\u1ec3m\t g\u1ea7n\t m\u1eb7t\t tr\u1eddi\t nh\u1ea5t)\t \u0111\u1ebfn\t \u0111i\u1ec3m\t c\u1eadn\t nh\u1eadt]\t th\u00ec g\u00f3c\t qu\u00e9t\t b\u1edfi\t \u0111\u01b0\u1eddng\t th\u1eb3ng\t n\u1ed1i\t m\u1eb7t\t tr\u1eddi\t v\u00e0\t h\u00e0nh\t tinh\t s\u1ebd\t kh\u00e1c\t v\u1edbi 360\u00b0.\tQu\u1ef9\t\u0111\u1ea1o\tc\u0169ng\tkh\u00f4ng\tph\u1ea3i\tl\u00e0\tm\u1ed9t\t\u0111\u01b0\u1eddng\tkh\u00e9p\tk\u00edn,\tm\u00e0\ttheo th\u1eddi\tgian\tn\u00f3\ts\u1ebd\tl\u1ea5p\t\u0111\u1ea7y\tph\u1ea7n\tv\u00e0nh\tc\u1ee7a\tm\u1eb7t\tph\u1eb3ng\tqu\u1ef9\t\u0111\u1ea1o\t(n\u1eb1m gi\u1eefa\t h\u00ecnh\t tr\u00f2n\t c\u1ee7a\t kho\u1ea3ng\t c\u00e1ch\t nh\u1ecf\t nh\u1ea5t,\t v\u00e0\t h\u00ecnh\t tr\u00f2n\t c\u1ee7a kho\u1ea3ng\tc\u00e1ch\tl\u1edbn\tnh\u1ea5t\tc\u1ee7a\th\u00e0nh\ttinh\t\u0111\u1ebfn\tm\u1eb7t\ttr\u1eddi). Theo\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng,\td\u0129\tnhi\u00ean\tkh\u00e1c\tv\u1edbi\tthuy\u1ebft\tNewton, m\u1ed9t\t s\u1ef1\t l\u1ec7ch\t nh\u1ecf\t nh\u01b0\t th\u1ebf\t \u0111\u1ed1i\t v\u1edbi\t chuy\u1ec3n\t \u0111\u1ed9ng\t qu\u1ef9\t \u0111\u1ea1o\t Kepler- Newton\t c\u0169ng\t s\u1ebd\t x\u1ea3y\t ra,\t v\u1edbi\t t\u00ednh\t ch\u1ea5t\t g\u00f3c\t qu\u00e9t\t b\u1edfi\t b\u00e1n\t k\u00ednh\t m\u1eb7t tr\u1eddi-h\u00e0nh\ttinh\tgi\u1eefa\thai\tl\u1ea7n\t\u0111i\u1ec3m\tc\u1eadn\tnh\u1eadt\tli\u00ean\tti\u1ebfp\tv\u01b0\u1ee3t\tqu\u00e1\tg\u00f3c c\u1ee7a\tm\u1ed9t\tv\u00f2ng\tquay\tho\u00e0n\tch\u1ec9nh\t(ngh\u0129a\tl\u00e0\t2\u03c0\ttrong\t\u0111\u01a1n\tv\u1ecb\t\u0111o\tg\u00f3c tuy\u1ec7t\t\u0111\u1ed1i\ttrong\tv\u1eadt\tl\u00fd)\tb\u1edfi\tm\u1ed9t\ttr\u1ecb\ts\u1ed1\tl\u00e0","(Trong\tn\u00e0y,\ta\tl\u00e0\tb\u00e1n\ttr\u1ee5c\tl\u1edbn\tc\u1ee7a\tellip,\te\tl\u00e0\tt\u00e2m\tsai\tc\u1ee7a\tn\u00f3,\tc\tl\u00e0 v\u1eadn\t t\u1ed1c\t \u00e1nh\t s\u00e1ng\t v\u00e0\t T\t l\u00e0\t th\u1eddi\t gian\t quay\t v\u00f2ng\t c\u1ee7a\t h\u00e0nh\t tinh). Ng\u01b0\u1eddi\t ta\t c\u0169ng\t c\u00f3\t th\u1ec3\t di\u1ec5n\t gi\u1ea3i\t \u0111i\u1ec1u\t n\u00e0y\t nh\u01b0\t sau:\t Theo\t thuy\u1ebft t\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng,\ttr\u1ee5c\tl\u1edbn\tc\u1ee7a\tellip\tquay\txung\tquanh\tm\u1eb7t\ttr\u1eddi\tnh\u01b0 chuy\u1ec3n\t \u0111\u1ed9ng\t qu\u1ef9\t \u0111\u1ea1o\t quanh\t m\u1eb7t\t tr\u1eddi\t c\u1ee7a\t h\u00e0nh\t tinh.\t \u0110\u1ed9\t quay n\u00e0y,\t nh\u01b0\t m\u1ed9t\t k\u1ebft\t qu\u1ea3\t c\u1ee7a\t l\u00fd\t thuy\u1ebft,\t c\u00f3\t tr\u1ecb\t s\u1ed1\t b\u1eb1ng\t 43\t gi\u00e2y\t cung trong\tm\u1ed9t\ttr\u0103m\tn\u0103m\t\u0111\u1ed1i\tv\u1edbi\tSao\tTh\u1ee7y,\tnh\u01b0ng\tl\u1ea1i\tqu\u00e1\tnh\u1ecf\t\u0111\u1ed1i\tv\u1edbi c\u00e1c\t h\u00e0nh\t tinh\t kh\u00e1c\t c\u1ee7a\t h\u1ec7\t m\u1eb7t\t tr\u1eddi\t c\u1ee7a\t ch\u00fang\t ta\t khi\u1ebfn\t n\u00f3\t vu\u1ed9t kh\u1ecfi\ts\u1ef1\tquan\ts\u00e1t.[69] Nh\u01b0\t m\u1ed9t\t s\u1ef1\t th\u1eadt,\t c\u00e1c\t nh\u00e0\t thi\u00ean\t v\u0103n\t h\u1ecdc\t \u0111\u00e3\t t\u00ecm\t th\u1ea5y\t thuy\u1ebft Newton\t kh\u00f4ng\t \u0111\u1ee7\t s\u1ee9c\t t\u00ednh\t to\u00e1n\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t quan\t s\u00e1t c\u1ee7a\t Sao\t Th\u1ee7y\t v\u1edbi\t \u0111\u1ed9\t ch\u00ednh\t x\u00e1c\t m\u00e0\t kh\u1ea3\t n\u0103ng\t quan\t s\u00e1t\t c\u1ee7a\t khoa h\u1ecdc\t h\u00f4m\t nay\t cho\t ph\u00e9p.\t Sau\t khi\t \u0111\u00e3\t \u0111\u1ec3\t \u00fd\t \u0111\u1ebfn\t c\u00e1c\t \u1ea3nh\t h\u01b0\u1edfng\t g\u00e2y r\u1ed1i\t l\u00ean\t Sao\t Th\u1ee7y\t t\u1eeb\t c\u00e1c\t h\u00e0nh\t tinh\t c\u00f2n\t l\u1ea1i,\t ng\u01b0\u1eddi\t ta\t t\u00ecm\t th\u1ea5y\t (Le Verrier,\t 1859\t v\u00e0\t Newkomb,\t 1895)\t v\u1eabn\t c\u00f2n\t t\u1ed3n\t t\u1ea1i\t m\u1ed9t\t chuy\u1ec3n \u0111\u1ed9ng\t kh\u00f4ng\t gi\u1ea3i\t th\u00edch\t \u0111\u01b0\u1ee3c\t c\u1ee7a\t \u0111i\u1ec3m\t c\u1eadn\t nh\u1eadt\t c\u1ee7a\t qu\u1ef9\t \u0111\u1ea1o\t Sao Th\u1ee7y\t v\u1edbi\t m\u1ed9t\t tr\u1ecb\t s\u1ed1\t kh\u00f4ng\t kh\u00e1c\t bao\t nhi\u00eau\t so\t v\u1edbi\t +43\t gi\u00e2y\t cung cho\tm\u1ed9t\tth\u1ebf\tk\u1ef7\t\u0111\u00e3\tn\u00f3i.\t\u0110\u1ed9\tc\u00e1ch\tbi\u1ec7t\tc\u1ee7a\tk\u1ebft\tqu\u1ea3\tth\u1ef1c\tnghi\u1ec7m\tn\u00e0y (k\u1ebft\tqu\u1ea3\ttr\u00f9ng\tkh\u1edbp\tv\u1edbi\tl\u00fd\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng)\tch\u1ec9\tl\u00e0\tv\u00e0i\tgi\u00e2y. B.\tS\u1ef0\tL\u1ec6CH\tC\u1ee6A\t\u00c1NH\tS\u00c1NG\tTRONG\tTR\u01af\u1edcNG\tH\u1ea4P\tD\u1eaaN Trong\t \u00a7\t 22\t ch\u00fang\t ta\t \u0111\u00e3\t tr\u00ecnh\t b\u00e0y\t r\u1eb1ng\t theo\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i r\u1ed9ng,\ttia\ts\u00e1ng\tph\u1ea3i\tch\u1ecbu\tm\u1ed9t\ts\u1ef1\tu\u1ed1n\tcong\tkhi\t\u0111i\tqua\tm\u1ed9t\ttr\u01b0\u1eddng h\u1ea5p\t d\u1eabn,\t gi\u1ed1ng\t nh\u01b0\t s\u1ef1\t u\u1ed1n\t cong\t m\u00e0\t qu\u1ef9\t \u0111\u1ea1o\t c\u1ee7a\t m\u1ed9t\t v\u1eadt\t th\u1ec3 chuy\u1ec3n\t \u0111\u1ed9ng\t xuy\u00ean\t qua\t tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn\t ph\u1ea3i\t ch\u1ecbu.\t Nh\u01b0\t m\u1ed9t\t h\u1ec7 qu\u1ea3\t thuy\u1ebft\t n\u00e0y,\t m\u1ed9t\t tia\t s\u00e1ng\t \u0111i\t ngang\t qua\t m\u1ed9t\t thi\u00ean\t th\u1ec3\t s\u1ebd\t b\u1ecb u\u1ed1n\tcong\tv\u1ec1\tph\u00eda\tthi\u00ean\tth\u1ec3.\tM\u1ed9t\ttia\ts\u00e1ng\t\u0111i\tqua\tm\u1eb7t\ttr\u1eddi,\tv\u1edbi\tm\u1ed9t kho\u1ea3ng\tc\u00e1ch\t\u0394\t(l\u1ea7n)\tb\u00e1n\tk\u00ednh\tm\u1eb7t\ttr\u1eddi[70],\ts\u1ebd\tc\u00f3\tg\u00f3c\tl\u1ec7ch\tc\u00f3\ttr\u1ecb\ts\u1ed1 b\u1eb1ng C\u1ea7n\t n\u00f3i\t th\u00eam\t r\u1eb1ng\t theo\t l\u00fd\t thuy\u1ebft,\t m\u1ed9t\t n\u1eeda\t \u0111\u1ed9\t l\u1ec7ch\t n\u00e0y\t l\u00e0\t do t\u00e1c\td\u1ee5ng\tc\u1ee7a\ttr\u01b0\u1eddng\th\u1ea5p\td\u1eabn\tNewton\tc\u1ee7a\tm\u1eb7t\ttr\u1eddi,\tm\u1ed9t\tn\u1eeda\tdo\ts\u1ef1 bi\u1ebfn\t d\u1ea1ng\t h\u00ecnh\t h\u1ecdc\t (\\\"s\u1ef1\t u\u1ed1n\t cong\\\")\t c\u1ee7a\t kh\u00f4ng\t gian\t g\u00e2y\t ra\t b\u1edfi m\u1eb7t\ttr\u1eddi. K\u1ebft\t qu\u1ea3\t n\u00e0y\t cho\t ph\u00e9p\t m\u1ed9t\t s\u1ef1\t th\u1ea9m\t tra\t th\u1ef1c\t nghi\u1ec7m\t b\u1eb1ng","ph\u01b0\u01a1ng\t ph\u00e1p\t ch\u1ee5p\t \u1ea3nh\t c\u00e1c\t v\u00ec\t sao\t v\u00e0o\t l\u00fac\t nh\u1eadt\t th\u1ef1c\t to\u00e0n\t ph\u1ea7n. S\u1edf\td\u0129\tch\u00fang\tta\tph\u1ea3i\tch\u1edd\t\u0111\u1ebfn\thi\u1ec7n\tt\u01b0\u1ee3ng\tn\u00e0y\tl\u00e0\tv\u00ec\tv\u00e0o\tnh\u1eefng\tth\u1eddi \u0111i\u1ec3m\tkh\u00e1c,\tb\u1ea7u\tkh\u00ed\tquy\u1ec3n\tb\u1ecb\tm\u1eb7t\ttr\u1eddi\tchi\u1ebfu\ts\u00e1ng\tm\u1ea1nh\tl\u00e0m\tch\u00f3i m\u1eaft\tkhi\u1ebfn\tkh\u00f4ng\tth\u1ec3\tth\u1ea5y\t\u0111\u01b0\u1ee3c\tc\u00e1c\tv\u00ec\tsao\tg\u1ea7n\tm\u1eb7t\ttr\u1eddi. 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Ch\u00fang\tta\tc\u00e1m\t\u01a1n\tVi\u1ec7n\th\u00e0n\tl\u00e2m\tAnh\tv\u00e0\tVi\u1ec7n\th\u00e0n\tl\u00e2m\tthi\u00ean\tv\u0103n Anh\tv\u1ec1\ts\u1ef1\tki\u1ec3m\ttra\ts\u1ef1\tki\u1ec7n\tquan\ttr\u1ecdng\tn\u00e0y.\tKh\u00f4ng\t\u0111\u1ec3\tn\u1ea3n\tl\u00f2ng\tv\u00ec chi\u1ebfn\t tranh\t (th\u1ebf\t gi\u1edbi\t l\u1ea7n\t th\u1ee9\t nh\u1ea5t)\t v\u00e0\t nh\u1eefng\t kh\u00f3\t kh\u0103n\t v\u1ec1\t m\u1eb7t t\u00e2m\tl\u00fd\tdo\tn\u00f3\tg\u00e2y\tra,\tc\u00e1c\tvi\u1ec7n\tn\u00e0y\t\u0111\u00e3\tg\u1eedi\tnhi\u1ec1u\tnh\u00e0\tthi\u00ean\tv\u0103n\th\u1ecdc t\u1ea7m\t c\u1ee1\t nh\u1ea5t\t (Eddington,\t Cottingham,\t Crommelin,\t Davidson)\t v\u00e0 trang\tb\u1ecb\thai\t\u0111o\u00e0n\tth\u00e1m\thi\u1ec3m\t\u0111\u1ec3\tc\u00f3\t\u0111\u01b0\u1ee3c\tnh\u1eefng\tt\u1ea5m\t\u1ea3nh\tc\u1ee7a\tnh\u1eadt th\u1ef1c\tv\u00e0o\tng\u00e0y\t19\tth\u00e1ng\t5\tn\u0103m\t1919\t\u1edf\tSobral\t(Brazil)\tv\u00e0\ttr\u00ean\t\u0111\u1ea3o Principe\t (T\u00e2y\t Phi).\t \u0110\u1ed9\t l\u1ec7ch\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t ng\u01b0\u1eddi\t ta\t ch\u1edd\t \u0111\u1ee3i\t gi\u1eefa\t c\u00e1c \u1ea3nh\t nh\u1eadt\t th\u1ef1c\t v\u00e0\t \u1ea3nh\t \u0111\u1ed1i\t chi\u1ebfu\t ch\u1ec9\t b\u1eb1ng\t v\u00e0i\t ph\u1ea7n\t tr\u0103m\t c\u1ee7a milim\u00e9t.\tCho\tn\u00ean\tnh\u1eefng\t\u0111\u00f2i\th\u1ecfi\tv\u1ec1\t\u0111\u1ed9\tch\u00ednh\tx\u00e1c\t\u0111\u01b0\u1ee3c\t\u0111\u1eb7t\tra\tcho vi\u1ec7c\tch\u1ee5p\t\u1ea3nh\tv\u00e0\t\u0111o\t\u0111\u1ea1c\tsau\t\u0111\u00f3\tl\u00e0\tkh\u00f4ng\tnh\u1ecf. K\u1ebft\tqu\u1ea3\t\u0111o\t\u0111\u1ea1c\t\u0111\u00e3\tx\u00e1c\tnh\u1eadn\tl\u00fd\tthuy\u1ebft\tm\u1ed9t\tc\u00e1ch\tho\u00e0n\tto\u00e0n\tth\u1ecfa \u0111\u00e1ng.\tC\u00e1c\tth\u00e0nh\tph\u1ea7n\tg\u00f3c\tc\u1ee7a\tc\u00e1c\t\u0111\u1ed9\tl\u1ec7ch,\ttheo\tquan\ts\u00e1t\tv\u00e0\ttheo t\u00ednh\t to\u00e1n\t t\u1eeb\t l\u00fd\t thuy\u1ebft\t c\u1ee7a\t c\u00e1c\t sao\t (t\u00ednh\t b\u1eb1ng\t gi\u00e2y\t cung)\t \u0111\u01b0\u1ee3c \u0111\u01b0\u1ee3c\ttr\u00ecnh\tb\u00e0y\ttrong\tb\u1ea3ng\td\u01b0\u1edbi\t\u0111\u00e2y[71]: S\u1ed1\tl\u01b0\u1ee3ng T\u1ecda\t\u0111\u1ed9\tth\u1ee9\tnh\u1ea5t T\u1ecda\t\u0111\u1ed9\tth\u1ee9\thai sao[72] theo\tquan theo\tt\u00ednh theo\tquan theo\tt\u00ednh s\u00e1t to\u00e1n s\u00e1t to\u00e1n 11 -\t0,19 -\t0,22 +\t0,16 +\t0,02 5 -\t0,29 -\t0,31 -\t0,46 -\t0,43 4 -\t0,11 -\t0,10 +\t0,83 +\t0,74 3 -\t0,20 -\t0,12 +\t1,00 +\t0,87 6 -\t0,10 -\t0,04 +\t0,57 +\t0,40","10 -\t0,08 +\t0,09 +\t0,35 +\t0,32 2 +\t0,95 +\t0,85 -\t0,27 -\t0,09 C.\tS\u1ef0\tD\u1ecaCH\tCHUY\u1ec2N\tC\u1ee6A\tC\u00c1C\tV\u1ea0CH\tQUANG\tPH\u1ed4\tV\u1ec0\tPH\u00cdA \u0110\u1ece[73] Trong\t \u00a7\t 23\t ch\u00fang\t ta\t \u0111\u00e3\t ch\u1ee9ng\t minh,\t trong\t m\u1ed9t\t h\u1ec7\t th\u1ed1ng\t K\u2019 chuy\u1ec3n\t\u0111\u1ed9ng\tquay\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7\tGalilei\tK,\tc\u00e1c\t\u0111\u1ed3ng\th\u1ed3\t\u0111\u01b0\u1ee3c\tc\u1ea5u t\u1ea1o\tgi\u1ed1ng\tnhau\tv\u00e0\t\u0111\u01b0\u1ee3c\txem\t\u0111\u1ee9ng\ty\u00ean\t\u0111\u1ed1i\tv\u1edbi\th\u1ec7\tquy\tchi\u1ebfu\tquay K\u2019\ts\u1ebd\tch\u1ea1y\tv\u1edbi\tc\u00e1c\tv\u1eadn\tt\u1ed1c\tl\u1ec7\tthu\u1ed9c\tv\u00e0o\tv\u1ecb\ttr\u00ed\tc\u1ee7a\tch\u00fang.\tCh\u00fang\tta mu\u1ed1n\t nghi\u00ean\t c\u1ee9u\t s\u1ef1\t l\u1ec7\t thu\u1ed9c\t n\u00e0y\t m\u1ed9t\t c\u00e1ch\t \u0111\u1ecbnh\t l\u01b0\u1ee3ng.\t M\u1ed9t \u0111\u1ed3ng\th\u1ed3,\tgi\u1ea3\tthi\u1ebft\t\u0111\u01b0\u1ee3c\t\u0111\u1eb7t\t\u1edf\tm\u1ed9t\tkho\u1ea3ng\tc\u00e1ch\tr\tt\u1eeb\ttrung\tt\u00e2m\t\u0111\u0129a quay\ts\u1ebd\tc\u00f3\tm\u1ed9t\tv\u1eadn\tt\u1ed1c\t\u0111\u1ed1i\tv\u1edbi\tK\t\u0111\u01b0\u1ee3c\tcho\tb\u1edfi\tc\u00f4ng\tth\u1ee9c v\t=\t\u03c9\tr trong\t\u0111\u00f3\t\u03c9\tl\u00e0\tv\u1eadn\tt\u1ed1c\tquay\tc\u1ee7a\t\u0111\u0129a\t(K\u2019)\t\u0111\u1ed1i\tv\u1edbi\tK.\tN\u1ebfu\tg\u1ecdi\tvo\tl\u00e0 s\u1ed1\tl\u1ea7n\tt\u00edc\tt\u1eafc\tc\u1ee7a\t\u0111\u1ed3ng\th\u1ed3\ttrong\t\u0111\u01a1n\tv\u1ecb\tgi\u00e2y\t(v\u1eadn\tt\u1ed1c\tc\u1ee7a\t\u0111\u1ed3ng\th\u1ed3) \u0111\u1ed1i\t v\u1edbi\t K,\t khi\t \u0111\u1ed3ng\t h\u1ed3\t \u0111\u1ee9ng\t y\u00ean,\t th\u00ec\t v\u1eadn\t t\u1ed1c\t v\t c\u1ee7a\t \u0111\u1ed3ng\t h\u1ed3 chuy\u1ec3n\t\u0111\u1ed9ng\tv\u1edbi\tv\u1eadn\tt\u1ed1c\tv\t\u0111\u1ed1i\tv\u1edbi\tK,\t\u0111\u1ee9ng\ty\u00ean\t\u0111\u1ed1i\tv\u1edbi\t\u0111\u0129a,\ttheo\t\u00a7 12\tl\u00e0 hay\tv\u1edbi\t\u0111\u1ed9\tch\u00ednh\tx\u00e1c\tth\u1ecfa\t\u0111\u00e1ng ho\u1eb7c\tc\u0169ng\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\tvi\u1ebft\tl\u1ea1i\td\u01b0\u1edbi\td\u1ea1ng N\u1ebfu\t ch\u00fang\t ta\t g\u1ecdi\t l\u00e0\t \u0424\t hi\u1ec7u\t s\u1ed1\t c\u1ee7a\t th\u1ebf[74]\t c\u1ee7a\t l\u1ef1c\t ly\t t\u00e2m\t gi\u1eefa \u0111i\u1ec3m\t v\u1ecb\t tr\u00ed\t c\u1ee7a\t \u0111\u1ed3ng\t h\u1ed3\t v\u00e0\t t\u00e2m\t \u0111i\u1ec3m\t c\u1ee7a\t \u0111\u0129a,\t ngh\u0129a\t l\u00e0\t c\u00f4ng[75] (\u0111\u01b0\u1ee3c\t xem\t \u00e2m)\t m\u00e0\t ng\u01b0\u1eddi\t ta\t c\u1ea7n\t th\u1ef1c\t hi\u1ec7n\t tr\u00ean\t m\u1ed9t\t \u0111\u01a1n\t v\u1ecb\t kh\u1ed1i l\u01b0\u1ee3ng\t ng\u01b0\u1ee3c\t v\u1edbi\t l\u1ef1c\t ly\t t\u00e2m,\t \u0111\u1ec3\t c\u00f3\t th\u1ec3\t di\t chuy\u1ec3n\t n\u00f3\t t\u1eeb\t v\u1ecb\t tr\u00ed\t c\u1ee7a","\u0111\u1ed3ng\t h\u1ed3\t tr\u00ean\t \u0111\u0129a\t \u0111ang\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u1ebfn\t t\u00e2m\t \u0111i\u1ec3m\t c\u1ee7a\t \u0111\u0129a,\t th\u00ec ch\u00fang\tta\tc\u00f3 Do\t\u0111\u00f3 Tr\u01b0\u1edbc\tnh\u1ea5t,\tch\u00fang\tta\tth\u1ea5y\tt\u1eeb\tbi\u1ec3u\tth\u1ee9c\tn\u00e0y,\thai\t\u0111\u1ed3ng\th\u1ed3\t\u0111\u01b0\u1ee3c c\u1ea5u\tt\u1ea1o\tgi\u1ed1ng\tnhau\ts\u1ebd\tch\u1ea1y\tv\u1edbi\thai\tv\u1eadn\tt\u1ed1c\tkh\u00e1c\tnhau\tn\u1ebfu\tch\u00fang \u0111\u01b0\u1ee3c\t\u0111\u1eb7t\tt\u1ea1i\thai\tkho\u1ea3ng\tc\u00e1ch\tkh\u00e1c\tnhau\tt\u1eeb\tt\u00e2m\t\u0111\u0129a.\tK\u1ebft\tqu\u1ea3\tn\u00e0y c\u0169ng\t\u0111\u00fang\tt\u1eeb\tquan\t\u0111i\u1ec3m\tc\u1ee7a\tm\u1ed9t\tng\u01b0\u1eddi\tquan\ts\u00e1t\tquay\ttheo\t\u0111\u0129a. Nh\u01b0ng\t b\u00e2y\t gi\u1edd,\t n\u1ebfu\t x\u00e9t\t \u0111o\u00e1n\t t\u1eeb\t \u0111\u0129a,\t c\u00f3\t m\u1ed9t\t tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn t\u1ed3n\tt\u1ea1i\tv\u1edbi\tth\u1ebf\tl\u00e0\t\u0424,\tcho\tn\u00ean\tk\u1ebft\tqu\u1ea3\tv\u1eeba\tt\u00ecm\tth\u1ea5y\tn\u00f3i\tchung\tc\u0169ng c\u00f3\tgi\u00e1\ttr\u1ecb\tcho\tc\u00e1c\ttr\u01b0\u1eddng\th\u1ea5p\td\u1eabn. H\u01a1n\t n\u1eefa,\t v\u00ec\t ch\u00fang\t ta\t \u0111\u01b0\u1ee3c\t ph\u00e9p\t xem\t m\u1ed9t\t nguy\u00ean\t t\u1eed\t ph\u00e1t\t ra c\u00e1c\tv\u1ea1ch\tquang\tph\u1ed5\tnh\u01b0\tm\u1ed9t\t\u0111\u1ed3ng\th\u1ed3,\tcho\tn\u00ean\tch\u00fang\tta\tc\u00f3\t\u0111\u1ecbnh l\u00fd: M\u1ed9t\t nguy\u00ean\t t\u1eed\t h\u1ea5p\t thu\t hay\t ph\u00e1t\t ra\t \u00e1nh\t s\u00e1ng\t v\u1edbi\t m\u1ed9t\t t\u1ea7n\t s\u1ed1\t l\u1ec7 thu\u1ed9c\tv\u00e0o\tth\u1ebf\tc\u1ee7a\ttr\u01b0\u1eddng\th\u1ea5p\td\u1eabn\tm\u00e0\tn\u00f3\tn\u1eb1m\ttrong\t\u0111\u00f3. T\u1ea7n\ts\u1ed1\tc\u1ee7a\tm\u1ed9t\tnguy\u00ean\tt\u1eed\t\u1edf\tb\u1ec1\tm\u1eb7t\tc\u1ee7a\tm\u1ed9t\tthi\u00ean\tth\u1ec3\tdo\t\u0111\u00f3\ts\u1ebd c\u00f3\tph\u1ea7n\tnh\u1ecf\th\u01a1n\tt\u1ea7n\ts\u1ed1\tc\u1ee7a\tm\u1ed9t\tnguy\u00ean\tt\u1eed\tc\u00f9ng\tnguy\u00ean\tt\u1ed1\t\u0111\u01b0\u1ee3c \u0111\u1eb7t\t trong\t kh\u00f4ng\t gian\t t\u1ef1\t do\t (hay\t tr\u00ean\t b\u1ec1\t m\u1eb7t\t c\u1ee7a\t m\u1ed9t\t thi\u00ean\t th\u1ec3 nh\u1ecf\th\u01a1n). B\u00e2y\tgi\u1edd,\tv\u00ec\t\u0424\t=\t-\tKM\/r,\ttrong\t\u0111\u00f3\tK\tl\u00e0\th\u1eb1ng\ts\u1ed1\th\u1ea5p\td\u1eabn\tNewton, M\t kh\u1ed1i\t l\u01b0\u1ee3ng\t c\u1ee7a\t thi\u00ean\t th\u1ec3,\t r\t b\u00e1n\t k\u00ednh\t c\u1ee7a\t thi\u00ean\t th\u1ec3,\t cho\t n\u00ean m\u1ed9t\ts\u1ef1\td\u1ecbch\tchuy\u1ec3n\tv\u1ec1\tv\u00f9ng\t\u0111\u1ecf\tc\u1ee7a\tc\u00e1c\tv\u1ea1ch\tquang\tph\u1ed5\t\u0111\u01b0\u1ee3c\tt\u1ea1o ra\ttr\u00ean\tb\u1ec1\tm\u1eb7t\tc\u1ee7a\tc\u00e1c\tthi\u00ean\tth\u1ec3,\tso\tv\u1edbi\tc\u00e1c\tv\u1ea1ch\tquang\tph\u1ed5\t\u0111\u01b0\u1ee3c t\u1ea1o\tra\t\u1edf\tb\u1ec1\tm\u1eb7t\tc\u1ee7a\ttr\u00e1i\t\u0111\u1ea5t,\tph\u1ea3i\tdi\u1ec5n\tra\tv\u1edbi\tm\u1ed9t\t\u0111\u1ed9\tl\u1ec7ch\tl\u00e0 Trong\t tr\u01b0\u1eddng\t h\u1ee3p\t c\u1ee7a\t m\u1eb7t\t tr\u1eddi,\t \u0111\u1ed9\t d\u1ecbch\t chuy\u1ec3n\t v\u1ec1\t ph\u00eda\t \u0111\u1ecf \u0111\u01b0\u1ee3c\tti\u00ean\t\u0111o\u00e1n\tb\u1edfi\tl\u00fd\tthuy\u1ebft\tc\u00f3\ttr\u1ecb\ts\u1ed1\tkho\u1ea3ng\thai\tph\u1ea7n\ttri\u1ec7u\tc\u1ee7a \u0111\u1ed9\t d\u00e0i\t s\u00f3ng.\t \u0110\u1ed1i\t v\u1edbi\t c\u00e1c\t v\u00ec\t sao\t c\u1ed1\t \u0111\u1ecbnh,\t m\u1ed9t\t s\u1ef1\t t\u00ednh\t to\u00e1n\t tin\t c\u1eady","kh\u00f4ng\t th\u1ec3\t c\u00f3\t \u0111\u01b0\u1ee3c,\t b\u1edfi\t c\u1ea3\t kh\u1ed1i\t l\u01b0\u1ee3ng\t M\t l\u1eabn\t b\u00e1n\t k\u00ednh\t r\t th\u00f4ng th\u01b0\u1eddng\tkh\u00f4ng\t\u0111\u01b0\u1ee3c\tbi\u1ebft. Nh\u01b0ng\t hi\u1ec7u\t \u1ee9ng\t n\u00e0y\t th\u1eadt\t s\u1ef1\t c\u00f3\t t\u1ed3n\t t\u1ea1i\t hay\t kh\u00f4ng,\t \u0111\u00f3\t l\u00e0\t m\u1ed9t c\u00e2u\th\u1ecfi\tch\u01b0a\t\u0111\u01b0\u1ee3c\tgi\u1ea3i\t\u0111\u00e1p\tm\u00e0\thi\u1ec7n\tt\u1ea1i\t(1920)\tc\u00e1c\tnh\u00e0\tthi\u00ean\tv\u0103n h\u1ecdc\t \u0111ang\t l\u00e0m\t vi\u1ec7c\t h\u1ebft\t s\u1ee9c\t kh\u1ea9n\t tr\u01b0\u01a1ng\t \u0111\u1ec3\t t\u00ecm\t l\u1eddi\t gi\u1ea3i\t cho\t n\u00f3. Trong\t tr\u01b0\u1eddng\t h\u1ee3p\t m\u1eb7t\t tr\u1eddi,\t b\u1edfi\t s\u1ef1\t nh\u1ecf\t b\u00e9\t c\u1ee7a\t hi\u1ec7u\t \u1ee9ng\t n\u00ean\t h\u00e3y c\u00f2n\t kh\u00f3\t kh\u0103n\t trong\t vi\u1ec7c\t quy\u1ebft\t \u0111\u1ecbnh\t v\u1ec1\t s\u1ef1\t t\u1ed3n\t t\u1ea1i\t c\u1ee7a\t n\u00f3.\t Trong khi\t Grebe\t v\u00e0\t Bachem\t (Bonn),\t d\u1ef1a\t tr\u00ean\t c\u01a1\t s\u1edf\t c\u1ee7a\t nh\u1eefng\t \u0111o\t \u0111\u1ea1c ri\u00eang\tc\u0169ng\tnh\u01b0\tnh\u1eefng\t\u0111o\t\u0111\u1ea1c\tc\u1ee7a\tEvershed\tv\u00e0\tSchwarzschild\ttr\u00ean c\u00e1c\td\u00e3y\tcyanogen,\t\u0111\u00e3\tkh\u1eb3ng\t\u0111\u1ecbnh\ts\u1ef1\tt\u1ed3n\tt\u1ea1i\tc\u1ee7a\thi\u1ec7u\t\u1ee9ng\tl\u00e0\tch\u1eafc ch\u1eafn,\t th\u00ec\t c\u00e1c\t nh\u00e0\t khoa\t h\u1ecdc\t kh\u00e1c,\t \u0111\u1eb7c\t bi\u1ec7t\t W.H.\tJulius\t v\u00e0\t S.John, tr\u00ean\tc\u01a1\ts\u1edf\tnh\u1eefng\t\u0111o\t\u0111\u1ea1c\tc\u1ee7a\th\u1ecd\t\u0111\u00e3\t\u0111i\t\u0111\u1ebfn\t\u00fd\tki\u1ebfn\tng\u01b0\u1ee3c\tl\u1ea1i. C\u00e1c\t \u0111\u1ed9\t d\u1ecbch\t chuy\u1ec3n\t trung\t b\u00ecnh\t c\u1ee7a\t c\u00e1c\t v\u1ea1ch\t v\u1ec1\t ph\u00eda\t quang ph\u1ed5\t\u00edt\tkh\u00fac\tx\u1ea1\th\u01a1n\tc\u1ee7a\tnh\u1eefng\ts\u00f3ng\td\u00e0i\tch\u1eafc\tch\u1eafn\tph\u1ea3i\t\u0111\u01b0\u1ee3c\tb\u1ed9c l\u1ed9\t ra\t qua\t c\u00e1c\t nghi\u00ean\t c\u1ee9u\t th\u1ed1ng\t k\u00ea\t \u1edf\t c\u00e1c\t v\u00ec\t sao\t c\u1ed1\t \u0111\u1ecbnh.\t Nh\u01b0ng cho\t \u0111\u1ebfn\t nay\t vi\u1ec7c\t nghi\u00ean\t c\u1ee9u\t c\u00e1c\t s\u1ed1\t li\u1ec7u\t c\u00f3\t \u0111\u01b0\u1ee3c\t v\u1eabn\t ch\u01b0a\t cho ph\u00e9p\t \u0111i\t \u0111\u1ebfn\t m\u1ed9t\t quy\u1ebft\t \u0111\u1ecbnh\t ch\u1eafc\t ch\u1eafn,\t r\u1eb1ng\t c\u00f3\t ph\u1ea3i\t c\u00e1c\t s\u1ef1\t d\u1ecbch chuy\u1ec3n\t kia\t th\u1ef1c\t s\u1ef1\t do\t l\u1ef1c\t h\u1ea5p\t d\u1eabn\t g\u00e2y\t n\u00ean\t hay\t kh\u00f4ng.\t C\u00e1c\t k\u1ebft qu\u1ea3\t c\u1ee7a\t quan\t s\u00e1t\t \u0111\u01b0\u1ee3c\t thu\t th\u1eadp\t v\u00e0\t th\u1ea3o\t lu\u1eadn\t chi\t ti\u1ebft\t t\u1eeb\t quan \u0111i\u1ec3m\t c\u1ee7a\t c\u00e2u\t h\u1ecfi\t l\u00e0m\t ch\u00fang\t ta\t quan\t t\u00e2m\t trong\t m\u1ed9t\t c\u00f4ng\t tr\u00ecnh c\u1ee7a\t E.\t Freundlich\t c\u00f3\t ti\u00eau\t \u0111\u1ec1\t \\\"Ki\u1ec3m\t tra\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng\\\" \\\"Priifung\t der\t allgemeinen\t Relativit\u00e3tstheorie\\\"\t (trong\t t\u1ea1p\t ch\u00ed\t Die Naturwissenschaften\t 1919,\t S\u1ed1\t 35,\t tr.\t 530,\t Nxb.\t Julius\t Springer, Berlin). Nh\u1eefng\tn\u0103m\tt\u1edbi\tnh\u1ea5t\t\u0111\u1ecbnh\ts\u1ebd\t\u0111em\tl\u1ea1i\tc\u00e2u\ttr\u1ea3\tl\u1eddi\tch\u1eafc\tch\u1eafn.\tN\u1ebfu s\u1ef1\td\u1ecbch\tchuy\u1ec3n\t\u0111\u1ecf\tc\u1ee7a\tc\u00e1c\tv\u1ea1ch\tquang\tph\u1ed5\tdo\tth\u1ebf\th\u1ea5p\td\u1eabn\tkh\u00f4ng t\u1ed3n\t t\u1ea1i,\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng\t s\u1ebd\t kh\u00f4ng\t \u0111\u1ee9ng\t v\u1eefng.\t M\u1eb7t\t kh\u00e1c, n\u1ebfu\t ngu\u1ed3n\t g\u1ed1c\t c\u1ee7a\t s\u1ef1\t chuy\u1ec3n\t d\u1ecbch\t \u0111\u01b0\u1ee3c\t x\u00e1c\t \u0111\u1ecbnh\t ch\u1eafc\t ch\u1eafn\t t\u1eeb th\u1ebf\th\u1ea5p\td\u1eabn[76]\tth\u00ec\ts\u1ef1\tnghi\u00ean\tc\u1ee9u\tc\u1ee7a\ts\u1ef1\td\u1ecbch\tchuy\u1ec3n\tc\u00e1c\tv\u1ea1ch\ts\u1ebd mang\t l\u1ea1i\t nh\u1eefng\t th\u00f4ng\t tin\t quan\t tr\u1ecdng\t v\u1ec1\t kh\u1ed1i\t l\u01b0\u1ee3ng\t c\u1ee7a\t c\u00e1c thi\u00ean\tth\u1ec3.","Ph\u1ee5\tL\u1ee5c\tIV C\u1ea5u\tTr\u00fac\tc\u1ee7a\tKh\u00f4ng\tGian\ttrong\tM\u1ed1i\tLi\u00ean\tH\u1ec7\tv\u1edbi\tThuy\u1ebft T\u01b0\u01a1ng\t\u0110\u1ed1i\tR\u1ed9ng (B\u1ed5\tsung\t\u00a7\t32) T\u1eeb\t l\u1ea7n\t xu\u1ea5t\t b\u1ea3n\t th\u1ee9\t nh\u1ea5t\t c\u1ee7a\t cu\u1ed1n\t s\u00e1ch\t nh\u1ecf\t n\u00e0y\t nh\u1eadn\t th\u1ee9c c\u1ee7a\tch\u00fang\tta\tv\u1ec1\tc\u1ea5u\ttr\u00fac\tc\u1ee7a\tkh\u00f4ng\tgian\t\u1edf\tm\u1ee9c\t\u0111\u1ed9\tl\u1edbn\t(\\\"b\u00e0i\tto\u00e1n v\u0169\t tr\u1ee5\t h\u1ecdc\\\")\t \u0111\u00e3\t c\u00f3\t b\u01b0\u1edbc\t ph\u00e1t\t tri\u1ec3n\t quan\t tr\u1ecdng\t m\u00e0\t m\u1ed9t\t s\u1ef1\t tr\u00ecnh b\u00e0y\t\u0111\u1ea1i\tch\u00fang\tv\u1ec1\t\u0111\u1ec1\tt\u00e0i\tl\u00e0\tc\u1ea7n\tthi\u1ebft. C\u00e1c\tsuy\tngh\u0129\tban\t\u0111\u1ea7u\tc\u1ee7a\tt\u00f4i\tv\u1ec1\t\u0111\u1ec1\tt\u00e0i\t\u0111\u00e3\t\u0111\u01b0\u1ee3c\td\u1ef1a\ttr\u00ean\thai\tgi\u1ea3 thuy\u1ebft\tsau\t\u0111\u00e2y: 1.\t C\u00f3\t m\u1ed9t\t m\u1eadt\t \u0111\u1ed9\t trung\t b\u00ecnh\t kh\u00e1c\t kh\u00f4ng\t (0)\t c\u1ee7a\t v\u1eadt\t ch\u1ea5t\t t\u1ed3n t\u1ea1i\ttrong\tc\u1ea3\tkh\u00f4ng\tgian,\tv\u00e0\tb\u1eb1ng\tnhau\t\u1edf\tkh\u1eafp)\tn\u01a1i. 2.\t \u0110\u1ed9\t l\u1edbn\t (hay\t \\\"b\u00e1n\t k\u00ednh\\\")\t c\u1ee7a\t kh\u00f4ng\t gian\t l\u00e0\t \u0111\u1ed9c\t l\u1eadp\t v\u1edbi\t th\u1eddi gian. Hai\tgi\u1ea3\tthuy\u1ebft\tn\u00e0y\t\u0111\u00e3\tch\u1ee9ng\tt\u1ecf,\ttheo\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng,\tl\u00e0 nh\u1ea5t\t qu\u00e1n\t nhau,\t nh\u01b0ng\t ch\u1ec9\t sau\t khi\t ng\u01b0\u1eddi\t ta\t th\u00eam\t v\u00e0o\t c\u00e1c ph\u01b0\u01a1ng\t tr\u00ecnh\t tr\u01b0\u1eddng\t m\u1ed9t\t s\u1ed1\t h\u1ea1ng\t c\u00f3\t t\u00ednh\t c\u00e1ch\t gi\u1ea3\t \u0111\u1ecbnh,\t kh\u00f4ng ph\u1ea3i\t do\t l\u00fd\t thuy\u1ebft\t \u0111\u00f2i\t h\u1ecfi,\t n\u00f3\t c\u0169ng\t kh\u00f4ng\t ph\u1ea3i\t l\u00e0\t t\u1ef1\t nhi\u00ean\t n\u1ebfu nh\u00ecn\tt\u1eeb\tquan\t\u0111i\u1ec3m\tl\u00fd\tthuy\u1ebft\t(\u0111\u00f3\tl\u00e0\t\\\"s\u1ed1\th\u1ea1ng\tv\u0169\ttr\u1ee5\th\u1ecdc\ttrong\tc\u00e1c ph\u01b0\u01a1ng\ttr\u00ecnh\ttr\u01b0\u1eddng\\\"). Gi\u1ea3\tthuy\u1ebft\t(2)\t\u0111\u1ed1i\tv\u1edbi\tt\u00f4i\ttr\u01b0\u1edbc\t\u0111\u00e2y\tl\u00e0\tkh\u00f4ng\ttr\u00e1nh\tkh\u1ecfi,\tv\u00ec\tt\u00f4i ngh\u0129,\tr\u1eddi\tkh\u1ecfi\tn\u00f3\tng\u01b0\u1eddi\tta\ts\u1ebd\tr\u01a1i\tv\u00e0o\tnh\u1eefng\tsuy\t\u0111o\u00e1n\tv\u00f4\tb\u1edd\tb\u1ebfn. Tuy\t nhi\u00ean\t trong\t nh\u1eefng\t n\u0103m\t 1920,\t nh\u00e0\t to\u00e1n\t h\u1ecdc\t Nga Friedman\t kh\u00e1m\t ph\u00e1\t r\u1eb1ng\t m\u1ed9t\t gi\u1ea3\t thuy\u1ebft\t kh\u00e1c\t m\u1edbi\t l\u00e0\t t\u1ef1\t nhi\u00ean h\u01a1n,\tn\u1ebfu\t\u0111\u1ee9ng\ttr\u00ean\tquan\t\u0111i\u1ec3m\tthu\u1ea7n\tt\u00fay\tl\u00fd\tthuy\u1ebft.\tM\u1ed9t\tc\u00e1ch\tc\u1ee5 th\u1ec3,\t \u00f4ng\t nh\u1eadn\t th\u1ea5y\t r\u1eb1ng\t c\u00f3\t th\u1ec3\t gi\u1eef\t l\u1ea1i\t gi\u1ea3\t thuy\u1ebft\t (1)\t m\u00e0\t kh\u00f4ng c\u1ea7n\t ph\u1ea3i\t \u0111\u01b0a\t v\u00e0o\t s\u1ed1\t h\u1ea1ng\t v\u0169\t tr\u1ee5\t h\u1ecdc\t v\u1ed1n\t \u00edt\t t\u1ef1\t nhi\u00ean\t h\u01a1n\t v\u00e0o ph\u01b0\u01a1ng\t tr\u00ecnh\t tr\u01b0\u1eddng\t c\u1ee7a\t l\u1ef1c\t h\u1ea5p\t d\u1eabn,\t n\u1ebfu\t ch\u00fang\t ta\t quy\u1ebft\t \u0111\u1ecbnh b\u1ecf\tgi\u1ea3\tthuy\u1ebft\ts\u1ed1\t(2).\tTh\u1ef1c\tv\u1eady,\tc\u00e1c\tph\u01b0\u01a1ng\ttr\u00ecnh\ttr\u01b0\u1eddng\tnguy\u00ean th\u1ee7y\t cho\t ph\u00e9p\t c\u00f3\t m\u1ed9t\t nghi\u1ec7m\t s\u1ed1\t ,\t trong\t \u0111\u00f3\t \\\"b\u00e1n\t k\u00ednh\t v\u0169\t tr\u1ee5\\\"\t l\u1ec7 thu\u1ed9c\tv\u00e0o\tth\u1eddi\tgian\t(kh\u00f4ng\tgian\tb\u00e0nh\ttr\u01b0\u1edbng).\tTrong\tngh\u0129a\tn\u00e0y, ng\u01b0\u1eddi\tta\tc\u00f3\tth\u1ec3\tn\u00f3i\tc\u00f9ng\tv\u1edbi\tFriedman\tr\u1eb1ng\tl\u00fd\tthuy\u1ebft\t\u0111\u00f2i\th\u1ecfi\tm\u1ed9t s\u1ef1\tb\u00e0nh\ttr\u01b0\u1edbng\tc\u1ee7a\tkh\u00f4ng\tgian. \u00cdt\t n\u0103m\t sau\t \u0111\u00f3,\t Hubble\t \u0111\u00e3\t ch\u1ee9ng\t minh\t b\u1eb1ng\t m\u1ed9t\t nghi\u00ean\t c\u1ee9u","\u0111\u1eb7c\tbi\u1ec7t\t\u1edf\tquang\tph\u1ed5\tc\u1ee7a\tnh\u1eefng\t\\\"tinh\tv\u00e2n\tngo\u00e0i\tthi\u00ean\th\u00e0\\\"[77]\t(c\u00e1c \\\"ng\u00e2n\th\u00e0\\\"),\tr\u1eb1ng\tc\u00e1c\tv\u1ea1ch\tph\u00e1t\tra\tt\u1eeb\tc\u00e1c\ttinh\tv\u00e2n\tn\u00e0y\tch\u1ecbu\tm\u1ed9t\ts\u1ef1 d\u1ecbch\t chuy\u1ec3n\t \u0111\u1ecf\t c\u00f3\t t\u00ednh\t ch\u1ea5t\t t\u0103ng\t \u0111\u1ec1u\t \u0111\u1eb7n\t v\u1edbi\t kho\u1ea3ng\t c\u00e1ch\t c\u1ee7a c\u00e1c\ttinh\tv\u00e2n.\tTheo\ts\u1ef1\thi\u1ec3u\tbi\u1ebft\thi\u1ec7n\tt\u1ea1i\tc\u1ee7a\tch\u00fang\tta,\t\u0111i\u1ec1u\tn\u00e0y\tc\u00f3 th\u1ec3\t\u0111\u01b0\u1ee3c\tdi\u1ec5n\tgi\u1ea3i\ttheo\tnguy\u00ean\tl\u00fd\tDoppler\tl\u00e0\tkh\u00f4ng\t g\u00ec\tkh\u00e1c\t h\u01a1n m\u1ed9t\t chuy\u1ec3n\t \u0111\u1ed9ng\t b\u00e0nh\t tr\u01b0\u1edbng\t c\u1ee7a\t h\u1ec7\t tinh\t t\u00fa\t tr\u00ean\t di\u1ec7n\t r\u1ed9ng, nh\u01b0\t theo\t y\u00eau\t c\u1ea7u\t c\u1ee7a\t c\u00e1c\t ph\u01b0\u01a1ng\t tr\u00ecnh\t tr\u01b0\u1eddng\t c\u1ee7a\t l\u1ef1c\t h\u1ea5p\t d\u1eabn qua\tnghi\u00ean\tc\u1ee9u\tc\u1ee7a\tFriedman.\tPh\u00e1t\thi\u1ec7n\tc\u1ee7a\tHubble\tdo\t\u0111\u00f3\ttrong ch\u1eebng\t m\u1ef1c\t n\u00e0o\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t xem\t nh\u01b0\t m\u1ed9t\t s\u1ef1\t x\u00e1c\t nh\u1eadn\t c\u1ee7a\t l\u00fd thuy\u1ebft. Nh\u01b0ng\tr\u1ed3i\tm\u1ed9t\tkh\u00f3\tkh\u0103n\tl\u1ea1\tth\u01b0\u1eddng\tx\u1ea3y\t\u0111\u1ebfn.\tS\u1ef1\tdi\u1ec5n\tgi\u1ea3i\tc\u00e1c\ts\u1ef1 d\u1ecbch\t chuy\u1ec3n\t v\u1ea1ch\t c\u1ee7a\t thi\u00ean\t h\u00e0\t \u0111\u01b0\u1ee3c\t kh\u00e1m\t ph\u00e1\t b\u1edfi\t Hubble\t nh\u01b0 m\u1ed9t\ts\u1ef1\tb\u00e0nh\ttr\u01b0\u1edbng\t(v\u1ec1\tl\u00fd\tthuy\u1ebft\th\u1ea7u\tnh\u01b0\tkh\u00f4ng\tnghi\tng\u1edd\tn\u1eefa) \u0111\u01b0a\t \u0111\u1ebfn\t m\u1ed9t\t s\u1ef1\t kh\u1edfi\t \u0111\u1ea7u\t c\u1ee7a\t s\u1ef1\t b\u00e0nh\t tr\u01b0\u1edbng\t n\u00e0y,\t x\u1ea3y\t ra\t \\\"ch\u1ec9\\\" c\u00e1ch\t \u0111\u00e2y\t kho\u1ea3ng\t 109\t n\u0103m,\t trong\t khi\t thi\u00ean\t v\u0103n\t h\u1ecdc\t v\u1eadt\t l\u00fd\t cho th\u1ea5y\tc\u00f3\tkh\u1ea3\tn\u0103ng,\tr\u1eb1ng\ts\u1ef1\tph\u00e1t\ttri\u1ec3n\tc\u00e1c\tv\u00ec\tsao\tc\u00e1\tnh\u00e2n\tv\u00e0\tc\u00e1c\th\u1ec7 th\u1ed1ng\ttinh\tt\u00fa\tc\u1ea7n\tnh\u1eefng\tth\u1eddi\tgian\t\u0111\u00e1ng\tk\u1ec3\tl\u00e2u\th\u01a1n.\tHi\u1ec7n\tt\u1ea1i\tv\u1eabn ch\u01b0a\t bi\u1ebft\t ch\u1eafc\t s\u1ef1\t kh\u00f4ng\t nh\u1ea5t\t qu\u00e1n\t n\u00e0y\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t v\u01b0\u1ee3t\t qua b\u1eb1ng\tc\u00e1ch\tn\u00e0o. T\u00f4i\tc\u0169ng\txin\tch\u00fa\tth\u00edch\tr\u1eb1ng\tl\u00fd\tthuy\u1ebft\tkh\u00f4ng\tgian\tb\u00e0nh\ttr\u01b0\u1edbng c\u00f9ng\t v\u1edbi\t nh\u1eefng\t d\u1eef\t li\u1ec7u\t th\u1ef1c\t nghi\u1ec7m\t ch\u01b0a\t cho\t ph\u00e9p\t k\u1ebft\t lu\u1eadn\t v\u1ec1 t\u00ednh\th\u1eefu\th\u1ea1n\thay\tv\u00f4\th\u1ea1n\tc\u1ee7a\tkh\u00f4ng\tgian\t(ba\tchi\u1ec1u),\ttrong\tkhi\tgi\u1ea3 thuy\u1ebft\t \\\"t\u0129nh\\\"\t ban\t \u0111\u1ea7u\t v\u1ec1\t kh\u00f4ng\t gian\t cho\t ph\u00e9p\t k\u1ebft\t lu\u1eadn\t s\u1ef1\t kh\u00e9p k\u00edn\t(t\u00ednh\th\u1eefu\th\u1ea1n)\tc\u1ee7a\tkh\u00f4ng\tgian.","Ph\u1ee5\tL\u1ee5c\tV Thuy\u1ebft\tT\u01b0\u01a1ng\t\u0110\u1ed1i\tv\u00e0\tV\u1ea5n\t\u0110\u1ec1\tKh\u00f4ng\tGian Trong\t l\u1ea7n\t t\u00e1i\t b\u1ea3n\t n\u00e0y\t (th\u1ee9\t m\u01b0\u1eddi\t l\u0103m,\t b\u1eb1ng\t ti\u1ebfng\t Anh),\t t\u00f4i\t \u0111\u00e3 th\u00eam,\tnh\u01b0\tm\u1ed9t\tph\u1ee5\tl\u1ee5c\tth\u1ee9\tn\u0103m,\tph\u1ea7n\ttr\u00ecnh\tb\u00e0y\tc\u00e1c\tquan\t\u0111i\u1ec3m c\u1ee7a\t t\u00f4i\t v\u1ec1\t v\u1ea5n\t \u0111\u1ec1\t c\u1ee7a\t kh\u00f4ng\t gian\t n\u00f3i\t chung,\t v\u00e0\t v\u1ec1\t nh\u1eefng\t thay \u0111\u1ed5i\tt\u1eebng\tb\u01b0\u1edbc\tc\u1ee7a\tc\u00e1c\t\u00fd\tt\u01b0\u1edfng\tc\u1ee7a\tch\u00fang\tt\u00f4i\tv\u1ec1\tkh\u00f4ng\tgian\tr\u00fat\tra t\u1eeb\t\u1ea3nh\th\u01b0\u1edfng\tc\u1ee7a\tquan\t\u0111i\u1ec3m\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i.\tT\u00f4i\tmu\u1ed1n\tch\u1ee9ng minh\t r\u1eb1ng\t kh\u00f4ng-th\u1eddi-gian\t kh\u00f4ng\t nh\u1ea5t\t thi\u1ebft\t l\u00e0\t c\u00e1i\t g\u00ec\t ng\u01b0\u1eddi\t ta c\u00f3\tth\u1ec3\tg\u00e1n\tcho\tn\u00f3\tm\u1ed9t\ts\u1ef1\tt\u1ed3n\tt\u1ea1i\tt\u00e1ch\tbi\u1ec7t,\t\u0111\u1ed9c\tl\u1eadp\tv\u1edbi\tc\u00e1c\tv\u1eadt\tth\u1ec3 th\u1ef1c\t c\u1ee7a\t th\u1ef1c\t t\u1ea1i\t v\u1eadt\t l\u00fd.\t C\u00e1c\t v\u1eadt\t th\u1ec3\t v\u1eadt\t l\u00fd\t kh\u00f4ng\t ph\u1ea3i\t \u1edf\t trong kh\u00f4ng\tgian,\tm\u00e0\tnh\u1eefng\tv\u1eadt\t th\u1ec3\tn\u00e0y\t l\u00e0\ts\u1ef1\tn\u1edbi\t r\u1ed9ng\tc\u1ee7a\t kh\u00f4ng gian.\t Theo\t c\u00e1ch\t n\u00e0y,\t kh\u00e1i\t ni\u1ec7m\t \\\"kh\u00f4ng\t gian\t r\u1ed7ng\\\"\t m\u1ea5t\t \u0111i\t \u00fd ngh\u0129a\tc\u1ee7a\tn\u00f3. EINSTEIN Ng\u00e0y\t9\tth\u00e1ng\t6\tn\u0103m\t1952 \u0110\u1eb7c\ttr\u01b0ng\tc\u1ee7a\tv\u1eadt\tl\u00fd\tNewton\tl\u00e0\tn\u00f3\tph\u1ea3i\tc\u00f4ng\tnh\u1eadn\tm\u1ed9t\ts\u1ef1\tt\u1ed3n t\u1ea1i\t th\u1ef1c\t v\u00e0\t \u0111\u1ed9c\t l\u1eadp\t cho\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian,\t b\u00ean\t c\u1ea1nh\t v\u1eadt ch\u1ea5t.\t B\u1edfi\t v\u00ec\t trong\t \u0111\u1ecbnh\t lu\u1eadt\t chuy\u1ec3n\t \u0111\u1ed9ng\t Newton\t kh\u00e1i\t ni\u1ec7m\t gia t\u1ed1c\t xu\u1ea5t\t hi\u1ec7n.\t Nh\u01b0ng\t trong\t thuy\u1ebft\t n\u00e0y,\t gia\t t\u1ed1c\t ch\u1ec9\t c\u00f3\t th\u1ec3\t c\u00f3 ngh\u0129a\tl\u00e0\t\\\"gia\tt\u1ed1c\t\u0111\u1ed1i\tv\u1edbi\tkh\u00f4ng\tgian\\\".\tKh\u00f4ng\tgian\tc\u1ee7a\tNewton\tdo \u0111\u00f3\t ph\u1ea3i\t \u0111\u01b0\u1ee3c\t quan\t ni\u1ec7m\t nh\u01b0\t \\\"y\u00ean\t t\u0129nh\\\",\t hay\t \u00edt\t nh\u1ea5t\t \\\"kh\u00f4ng\t gia t\u1ed1c\\\",\t \u0111\u1ec3\t ng\u01b0\u1eddi\t ta\t c\u00f3\t th\u1ec3\t xem\t gia\t t\u1ed1c\t xu\u1ea5t\t hi\u1ec7n\t trong\t \u0111\u1ecbnh\t lu\u1eadt chuy\u1ec3n\t\u0111\u1ed9ng\tl\u00e0\tm\u1ed9t\t\u0111\u1ea1i\tl\u01b0\u1ee3ng\tc\u00f3\t\u00fd\tngh\u0129a.\tC\u0169ng\tt\u01b0\u01a1ng\tt\u1ef1\tnh\u01b0\tth\u1ebf \u0111\u1ed1i\t v\u1edbi\t th\u1eddi\t gian,\t \u0111\u1ea1i\t l\u01b0\u1ee3ng\t c\u0169ng\t \u0111i\t v\u00e0o\t kh\u00e1i\t ni\u1ec7m\t gia\t t\u1ed1c.\t B\u1ea3n th\u00e2n\t Newton\t v\u00e0\t nh\u1eefng\t ng\u01b0\u1eddi\t \u0111\u01b0\u01a1ng\t th\u1eddi\t c\u00f3\t \u00f3c\t ph\u00ea\t ph\u00e1n\t \u00f4ng c\u0169ng\t \u0111\u00e3\t c\u1ea3m\t th\u1ea5y\t s\u1ef1\t kh\u00f3\t ch\u1ecbu\t khi\t ng\u01b0\u1eddi\t ta\t ph\u1ea3i\t th\u1eeba\t nh\u1eadn\t cho kh\u00f4ng\t gian\t l\u1eabn\t tr\u1ea1ng\t th\u00e1i\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t n\u00f3\t m\u1ed9t\t th\u1ef1c\t t\u1ea1i\t v\u1eadt l\u00fd;\t nh\u01b0ng\t l\u00fac\t b\u1ea5y\t gi\u1edd\t kh\u00f4ng\t c\u00f3\t l\u1ed1i\t tho\u00e1t\t n\u00e0o\t kh\u00e1c\t khi\t ng\u01b0\u1eddi\t ta mu\u1ed1n\tcho\tc\u01a1\th\u1ecdc\tm\u1ed9t\t\u00fd\tngh\u0129a\ts\u00e1ng\ts\u1ee7a. Th\u1eadt\t l\u00e0\t m\u1ed9t\t y\u00eau\t s\u00e1ch\t kh\u00f3\t kh\u0103n\t khi\t ng\u01b0\u1eddi\t ta\t n\u00f3i\t chung\t ph\u1ea3i th\u1eeba\t nh\u1eadn\t cho\t kh\u00f4ng\t gian\t m\u1ed9t\t th\u1ef1c\t t\u1ea1i\t v\u1eadt\t l\u00fd,\t \u0111\u1eb7c\t bi\u1ec7t\t kh\u00f4ng gian\t r\u1ed7ng.\t C\u00e1c\t nh\u00e0\t tri\u1ebft\t h\u1ecdc\t t\u1eeb\t nh\u1eefng\t th\u1eddi\t xa\t x\u01b0a\t nh\u1ea5t\t \u0111\u00e3\t lu\u00f4n l\u1eb7p\t l\u1ea1i\t s\u1ef1\t ch\u1ed1ng\t \u0111\u1ed1i\t m\u1ed9t\t y\u00eau\t s\u00e1ch\t nh\u01b0\t th\u1ebf.\t Ch\u1eb3ng\t h\u1ea1n\t Descartes l\u00fd\t lu\u1eadn\t nh\u01b0\t sau:\t Kh\u00f4ng\t gian\t v\u1ec1\t b\u1ea3n\t ch\u1ea5t\t \u0111\u1ed3ng\t nh\u1ea5t\t v\u1edbi\t s\u1ef1\t n\u1edbi","r\u1ed9ng[78].\t Nh\u01b0ng\t s\u1ef1\t n\u1edbi\t r\u1ed9ng\t l\u1ea1i\t d\u00ednh\t li\u1ec1n\t v\u1edbi\t v\u1eadt\t th\u1ec3.\t Nh\u01b0\t v\u1eady kh\u00f4ng\tth\u1ec3\tc\u00f3\tkh\u00f4ng\tgian\tm\u00e0\tkh\u00f4ng\tc\u00f3\tv\u1eadt\tth\u1ec3,\tngh\u0129a\tl\u00e0\tkh\u00f4ng\tc\u00f3 kh\u00f4ng\t gian\t r\u1ed7ng.\t \u0110i\u1ec3m\t y\u1ebfu\t c\u1ee7a\t c\u00e1ch\t l\u00fd\t lu\u1eadn\t n\u00e0y\t ch\u1ee7\t y\u1ebfu\t n\u1eb1m\t \u1edf ch\u1ed7:\t tuy\t kh\u00e1i\t ni\u1ec7m\t n\u1edbi\t r\u1ed9ng\t \u0111\u00fang\t l\u00e0\t c\u00f3\t ngu\u1ed3n\t g\u1ed1c\t t\u1eeb\t kinh nghi\u1ec7m\t ch\u00fang\t ta\t khi\t s\u1eafp\t x\u1ebfp\t c\u00e1c\t v\u1eadt\t th\u1ec3\t r\u1eafn\t (ti\u1ebfp\t x\u00fac\t ch\u00fang). Nh\u01b0ng\t t\u1eeb\t \u0111\u00f3\t ch\u00fang\t ta\t kh\u00f4ng\t th\u1ec3\t k\u1ebft\t lu\u1eadn\t r\u1eb1ng\t kh\u00e1i\t ni\u1ec7m\t n\u1edbi r\u1ed9ng\tl\u00e0\tkh\u00f4ng\tch\u00ednh\t\u0111\u00e1ng\ttrong\tnh\u1eefng\ttr\u01b0\u1eddng\th\u1ee3p\tkh\u00f4ng\tph\u1ea3i\tl\u00e0 nguy\u00ean\t nh\u00e2n\t cho\t s\u1ef1\t t\u1ea1o\t th\u00e0nh\t kh\u00e1i\t ni\u1ec7m\t n\u00e0y.\t M\u1ed9t\t s\u1ef1\t n\u1edbi\t r\u1ed9ng nh\u01b0\tth\u1ebf\tc\u1ee7a\tc\u00e1c\tkh\u00e1i\tni\u1ec7m\tc\u00f3\tth\u1ec3\tc\u0169ng\t\u0111\u01b0\u1ee3c\tbi\u1ec7n\tminh\tm\u1ed9t\tc\u00e1ch gi\u00e1n\tti\u1ebfp\tb\u1edfi\tgi\u00e1\ttr\u1ecb\tc\u1ee7a\tch\u00fang\tcho\tvi\u1ec7c\thi\u1ec3u\tbi\u1ebft\tc\u00e1c\tk\u1ebft\tqu\u1ea3\tth\u1ef1c nghi\u1ec7m.\t Cho\t n\u00ean\t b\u1ea3o\t r\u1eb1ng\t s\u1ef1\t n\u1edbi\t r\u1ed9ng\t l\u00e0\t g\u1eafn\t li\u1ec1n\t v\u1edbi\t v\u1eadt\t th\u1ec3\t t\u1ef1 n\u00f3\tth\u1eadt\ts\u1ef1\tkh\u00f4ng\tc\u00f3\tc\u01a1\ts\u1edf. Tuy\t nhi\u00ean,\t ch\u00fang\t ta\t s\u1ebd\t th\u1ea5y\t sau\t n\u00e0y\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng x\u00e1c\tnh\u1eadn\tquan\t\u0111i\u1ec3m\tc\u1ee7a\tDescartes\tqua\tm\u1ed9t\t\u0111\u01b0\u1eddng\tv\u00f2ng.\tC\u00e1i\tg\u00ec\t\u0111\u00e3 \u0111\u01b0a\tDescartes\t\u0111\u1ebfn\tquan\tni\u1ec7m\tl\u1ea1\tl\u00f9ng\tc\u1ee7a\t\u00f4ng,\t\u0111\u00f3\tc\u00f3\tl\u1ebd\tl\u00e0\tc\u00e1i\tc\u1ea3m gi\u00e1c,\t r\u1eb1ng\t n\u1ebfu\t kh\u00f4ng\t c\u00f3\t m\u1ed9t\t s\u1ef1\t c\u1ea7n\t thi\u1ebft\t c\u1ea5p\t b\u00e1ch,\t ng\u01b0\u1eddi\t ta kh\u00f4ng\t\u0111\u01b0\u1ee3c\tph\u00e9p\tg\u00e1n\tm\u1ed9t\tth\u1ef1c\tt\u1ea1i\tv\u1eadt\tl\u00fd\tcho\tm\u1ed9t\t\\\"v\u1eadt\tth\u1ec3\tkh\u00f4ng th\u1ec3\ttr\u1ef1c\tti\u1ebfp\ttr\u1ea3i\tnghi\u1ec7m\t\u0111\u01b0\u1ee3c\\\"\tnh\u01b0\tkh\u00f4ng\tgian.[79] Ngu\u1ed3n\t g\u1ed1c\t t\u00e2m\t l\u00fd\t c\u1ee7a\t kh\u00e1i\t ni\u1ec7m\t kh\u00f4ng\t gian,\t hay\t c\u1ee7a\t s\u1ef1\t c\u1ea7n thi\u1ebft\t c\u1ee7a\t n\u00f3,\t ch\u1eb3ng\t ph\u1ea3i\t l\u00e0\t hi\u1ec3n\t nhi\u00ean\t nh\u01b0\t ch\u00fang\t ta\t \u0111\u00e3\t quan ni\u1ec7m\t khi\t d\u1ef1a\t tr\u00ean\t c\u01a1\t s\u1edf\t c\u1ee7a\t c\u00e1c\t th\u00f3i\t quen\t t\u01b0\t duy.\t C\u00e1c\t nh\u00e0\t h\u00ecnh h\u1ecdc\t c\u1ed5\t x\u01b0a\t nghi\u00ean\t c\u1ee9u\t nh\u1eefng\t v\u1eadt\t th\u1ec3\t c\u00f3\t t\u00ednh\t ch\u1ea5t\t kh\u00e1i\t ni\u1ec7m (\u0111\u01b0\u1eddng\t th\u1eb3ng,\t \u0111i\u1ec3m,\t b\u1ec1\t m\u1eb7t)\t nh\u01b0ng\t kh\u00f4ng\t nghi\u00ean\t c\u1ee9u\t kh\u00f4ng gian\t nh\u01b0\t ch\u00ednh\t n\u00f3,\t nh\u01b0\t sau\t n\u00e0y\t h\u00ecnh\t h\u1ecdc\t gi\u1ea3i\t t\u00edch\t l\u00e0m.\t Tuy nhi\u00ean\tkh\u00e1i\tni\u1ec7m\tkh\u00f4ng\tgian\t\u0111\u01b0\u1ee3c\tg\u1ee3i\tra\tb\u1edfi\tm\u1ed9t\ts\u1ed1\tkinh\tnghi\u1ec7m s\u01a1\tkhai\tnh\u1ea5t\t\u0111\u1ecbnh.\tGi\u1ea3\tthi\u1ebft\tch\u00fang\tta\tl\u00e0m\tm\u1ed9t\tc\u00e1i\th\u1ed9p.\tC\u00e1c\t\u0111\u1ed3\tv\u1eadt c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t s\u1eafp\t x\u1ebfp\t v\u00e0o\t theo\t m\u1ed9t\t c\u00e1ch\t n\u00e0o\t \u0111\u1ea5y\t sao\t cho\t n\u00f3\t \u0111\u1ea7y. Kh\u1ea3\tn\u0103ng\tc\u1ee7a\tnh\u1eefng\ts\u1ef1\ts\u1eafp\tx\u1ebfp\tnh\u01b0\tth\u1ebf,\t\u0111\u00f3\tl\u00e0\tt\u00ednh\tch\u1ea5t\tc\u1ee7a\t\u0111\u1ed1i t\u01b0\u1ee3ng\t v\u1eadt\t ch\u1ea5t\t \\\"h\u1ed9p\\\",\t t\u1ee9c\t m\u1ed9t\t c\u00e1i\t g\u00ec\t \u0111\u01b0\u1ee3c\t cho\t c\u00f9ng\t v\u1edbi\t c\u00e1i\t h\u1ed9p: c\u00e1i\t\\\"kh\u00f4ng\tgian\t\u0111\u01b0\u1ee3c\tbao\tquanh\tb\u1edfi\tc\u00e1i\th\u1ed9p\\\".\t\u0110\u00f3\tl\u00e0\tm\u1ed9t\tc\u00e1i\tg\u00ec,\tc\u00f3 t\u00ednh\t ch\u1ea5t\t kh\u00e1c\t nhau\t v\u1edbi\t nh\u1eefng\t c\u00e1i\t h\u1ed9p\t kh\u00e1c\t nhau,\t m\u1ed9t\t c\u00e1i\t g\u00ec \u0111\u01b0\u1ee3c\t ngh\u0129\t nh\u01b0\t ho\u00e0n\t to\u00e0n\t t\u1ef1\t nhi\u00ean\t v\u00e0\t \u0111\u1ed9c\t l\u1eadp\t v\u1edbi\t vi\u1ec7c,\t c\u00f3\t hay kh\u00f4ng\t \u0111\u1ed1i\t t\u01b0\u1ee3ng\t n\u00e0o\t trong\t h\u1ed9p\t n\u00f3i\t chung.\t N\u1ebfu\t kh\u00f4ng\t c\u00f3\t \u0111\u1ed1i t\u01b0\u1ee3ng\tn\u00e0o\tn\u1eb1m\ttrong\th\u1ed9p,\tkh\u00f4ng\tgian\tc\u1ee7a\tn\u00f3\ttr\u00f4ng\tnh\u01b0\t\\\"r\u1ed7ng\\\". Cho\t\u0111\u1ebfn\tnay,\tkh\u00e1i\tni\u1ec7m\tkh\u00f4ng\tgian\tc\u1ee7a\tch\u00fang\tta\tg\u1eafn\tli\u1ec1n\tv\u1edbi c\u00e1i\t h\u1ed9p.\t Nh\u01b0ng\t th\u1eadt\t ra\t nh\u1eefng\t kh\u1ea3\t n\u0103ng\t ch\u1ee9a\t \u0111\u1ef1ng\t l\u00e0m\t th\u00e0nh kh\u00f4ng-gian-h\u1ed9p\tl\u00e0\t\u0111\u1ed9c\tl\u1eadp\tv\u1edbi\t\u0111\u1ed9\t\u0111\u00e0y\tc\u1ee7a\tc\u00e1c\tb\u1ee9c\tt\u01b0\u1eddng\tc\u1ee7a\th\u1ed9p.","C\u00f3\t th\u1ec3\t n\u00e0o\t ng\u01b0\u1eddi\t ta\t cho\t \u0111\u1ed9\t d\u1ea7y\t n\u00e0y\t ti\u1ebfn\t d\u1ea7n\t v\u1ec1\t s\u1ed1\t kh\u00f4ng,\t m\u00e0 kh\u00f4ng\t l\u00e0m\t cho\t \\\"kh\u00f4ng\t gian\\\"\t b\u1ecb\t m\u1ea5t\t \u0111i\t t\u1eeb\t \u0111\u00f3\t hay\t kh\u00f4ng?\t T\u00ednh ch\u1ea5t\tt\u1ef1\tnhi\u00ean\tc\u1ee7a\tm\u1ed9t\tqu\u00e1\ttr\u00ecnh\tt\u1edbi\th\u1ea1n\tnh\u01b0\tth\u1ebf\tl\u00e0\thi\u1ec3n\tnhi\u00ean,\tv\u00e0 gi\u1edd\t v\u1eabn\t c\u00f2n\t t\u1ed3n\t t\u1ea1i\t trong\t t\u01b0\t duy\t ch\u00fang\t ta\t kh\u00f4ng\t gian\t kh\u00f4ng\t c\u00f3 c\u00e1i\t h\u1ed9p,\t m\u1ed9t\t v\u1eadt\t t\u1ef1\t th\u00e2n\t c\u1ee7a\t n\u00f3,\t nh\u01b0ng\t l\u1ea1i\t l\u00e0\t m\u1ed9t\t th\u1ee9\t th\u1ef1c\t ra kh\u00f4ng\tth\u1eadt,\tn\u1ebfu\tch\u00fang\tta\tqu\u00ean\t\u0111i\tngu\u1ed3n\tg\u1ed1c\tc\u1ee7a\tkh\u00e1i\tni\u1ec7m\tn\u00e0y. Ng\u01b0\u1eddi\t ta\t hi\u1ec3u\t t\u1ea1i\t sao\t Descartes\t l\u1ea1i\t ph\u1ea3n\t kh\u00e1ng\t vi\u1ec7c\t xem\t kh\u00f4ng gian\t nh\u01b0\t m\u1ed9t\t v\u1eadt\t \u0111\u1ed9c\t l\u1eadp\t v\u1edbi\t c\u00e1c\t \u0111\u1ed1i\t t\u01b0\u1ee3ng\t v\u1eadt\t th\u1ec3,\t m\u1ed9t\t v\u1eadt\t c\u00f3 th\u1ec3\t t\u1ed3n\t t\u1ea1i\t m\u00e0\t kh\u00f4ng\t c\u1ea7n\t \u0111\u1ebfn\t v\u1eadt\t ch\u1ea5t[80]\t (tuy\t nhi\u00ean\t \u0111i\u1ec1u\t n\u00e0y kh\u00f4ng\t ng\u0103n\t \u00f4ng\t xem\t kh\u00f4ng\t gian\t nh\u01b0\t m\u1ed9t\t kh\u00e1i\t ni\u1ec7m\t c\u01a1\t b\u1ea3n trong\t h\u00ecnh\t h\u1ecdc\t gi\u1ea3i\t t\u00edch\t c\u1ee7a\t \u00f4ng\t ta).\t M\u1ed9t\t s\u1ef1\t l\u01b0u\t \u00fd\t \u0111\u1ebfn\t kho\u1ea3ng ch\u00e2n\tkh\u00f4ng\ttrong\th\u00e0n\tth\u1eed\tbi\u1ec3u\tth\u1ee7y\tng\u00e2n\tch\u1eafc\tch\u1eafn\t\u0111\u00e3\tt\u01b0\u1edbc\tv\u0169 kh\u00ed\tc\u1ee7a\tnh\u1eefng\tng\u01b0\u1eddi\tcu\u1ed1i\tc\u00f9ng\ttheo\tch\u1ee7\tngh\u0129a\tDescartes.\tNh\u01b0ng ng\u01b0\u1eddi\t ta\t kh\u00f4ng\t th\u1ec3\t ch\u1ed1i\t c\u00e3i\t \u0111\u01b0\u1ee3c\t r\u1eb1ng\t ngay\t trong\t giai\t \u0111o\u1ea1n\t s\u01a1 khai\t n\u00e0y,\t kh\u00e1i\t ni\u1ec7m\t kh\u00f4ng\t gian,\t hay\t ch\u00ednh\t kh\u00f4ng\t gian,\t \u0111\u01b0\u1ee3c quan\tni\u1ec7m\tnh\u01b0\tm\u1ed9t\tv\u1eadt\tth\u1ef1c,\t\u0111\u1ed9c\tl\u1eadp,\t\u0111\u00e3\tmang\ttrong\tm\u00ecnh\tm\u1ed9t c\u00e1i\tg\u00ec\tkh\u00f4ng\tth\u1ecfa\t\u0111\u00e1ng. Nh\u1eefng\t c\u00e1ch\t g\u00f3i\t gh\u00e9m\t c\u00e1c\t v\u1eadt\t th\u1ec3\t v\u00e0o\t kh\u00f4ng\t gian\t (ch\u1eb3ng\t h\u1ea1n c\u00e1i\th\u1ed9p)\tl\u00e0\t\u0111\u1ec1\tt\u00e0i\tc\u1ee7a\th\u00ecnh\th\u1ecdc\tEuclid\tba\tchi\u1ec1u\tm\u00e0\tc\u1ea5u\ttr\u00fac\tti\u00ean\t\u0111\u1ec1 c\u1ee7a\t n\u00f3\t d\u1ec5\t d\u00e0ng\t l\u1eeba\t ch\u00fang\t ta\t \u0111\u1ec3\t qu\u00ean\t \u0111i\t r\u1eb1ng\t n\u00f3\t d\u1ef1a\t tr\u00ean\t c\u00e1c ho\u00e0n\tc\u1ea3nh\tc\u00f3\tth\u1ec3\ttr\u1ea3i\tnghi\u1ec7m\t\u0111\u01b0\u1ee3c. N\u1ebfu\tgi\u1edd\tkh\u00e1i\tni\u1ec7m\tkh\u00f4ng\tgian\t\u0111\u01b0\u1ee3c\th\u00ecnh\tth\u00e0nh\tnh\u01b0\tc\u00e1ch\tth\u1ee9c \u0111\u00e3\tph\u00e1c\tth\u1ea3o\t\u1edf\ttr\u00ean\tv\u00e0\t\u0111\u01b0\u1ee3c\tg\u1eafn\tli\u1ec1n\tv\u1edbi\tkinh\tnghi\u1ec7m\tv\u1ec1\t\\\"l\u1ea5p\t\u0111\u1ea7y\\\" c\u00e1i\th\u1ed9p,\tth\u00ec\ttr\u01b0\u1edbc\tti\u00ean\t\u0111\u00e2y\tl\u00e0\tm\u1ed9t\tkh\u00f4ng\tgian\tgi\u1edbi\th\u1ea1n.\tTuy\tnhi\u00ean t\u00ednh\t gi\u1edbi\t h\u1ea1n\t t\u1ecf\t ra\t kh\u00f4ng\t quan\t tr\u1ecdng,\t b\u1edfi\t v\u00ec\t r\u00f5\t r\u00e0ng\t m\u1ed9t\t h\u1ed9p\t l\u1edbn h\u01a1n\t lu\u00f4n\t lu\u00f4n\t c\u00f3\t th\u1ec3\t ch\u1ee9a\t \u0111\u1ef1ng\t m\u1ed9t\t c\u00e1i\t h\u1ed9p\t nh\u1ecf\t h\u01a1n.\t Kh\u00f4ng gian\tdo\t\u0111\u00f3\tt\u1ecf\tra\tl\u00e0\tm\u1ed9t\tc\u00e1i\tg\u00ec\tkh\u00f4ng\tc\u00f3\tgi\u1edbi\th\u1ea1n. Nh\u01b0ng\t \u1edf\t \u0111\u00e2y\t t\u00f4i\t kh\u00f4ng\t mu\u1ed1n\t b\u00e0n\t c\u00e1c\t quan\t ni\u1ec7m\t v\u1ec1\t t\u00ednh\t ba chi\u1ec1u\tv\u00e0\t\\\"t\u00ednh\tEuclid\\\"\tc\u1ee7a\tkh\u00f4ng\tgian\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\ttruy\tnguy\u00ean\tt\u1eeb nh\u1eefng\t kinh\t nghi\u1ec7m\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t s\u01b0\t khai\t nh\u01b0\t th\u1ebf\t n\u00e0o.\t M\u00e0\t \u0111\u00fang h\u01a1n,\t tr\u01b0\u1edbc\t ti\u00ean\t t\u00f4i\t mu\u1ed1n\t xem\t x\u00e9t,\t nh\u00ecn\t t\u1eeb\t nh\u1eefng\t quan\t \u0111i\u1ec3m kh\u00e1c,\tvai\ttr\u00f2\tc\u1ee7a\tkh\u00e1i\tni\u1ec7m\tkh\u00f4ng\tgian\ttrong\ts\u1ef1\tph\u00e1t\ttri\u1ec3n\tc\u1ee7a\tt\u01b0 duy\tv\u1eadt\tl\u00fd. 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Khoa\t h\u1ecdc\t \u0111\u00e3\t ti\u1ebfp\t nh\u1eadn\t c\u00e1c\t kh\u00e1i\t ni\u1ec7m\t kh\u00f4ng\t gian,\t th\u1eddi\t gian,","\u0111\u1ed1i\tt\u01b0\u1ee3ng\tv\u1eadt\tth\u1ec3\t(v\u1edbi\ttr\u01b0\u1eddng\th\u1ee3p\t\u0111\u1eb7c\tbi\u1ec7t\tquan\ttr\u1ecdng\tl\u00e0\t\\\"v\u1eadt\tth\u1ec3 r\u1eafn\\\")\t t\u1eeb\t t\u01b0\t duy\t ti\u1ec1n-khoa-h\u1ecdc,\t c\u1ea3i\t bi\u00ean\t v\u00e0\t l\u00e0m\t cho\t ch\u00fang\t ch\u00ednh x\u00e1c\t h\u01a1n.\t \u0110\u00f3ng\t g\u00f3p\t quan\t tr\u1ecdng\t \u0111\u1ea7u\t ti\u00ean\t c\u1ee7a\t n\u00f3\t l\u00e0\t s\u1ef1\t ph\u00e1t\t tri\u1ec3n h\u00ecnh\t h\u1ecdc\t Euclid.\t C\u00e1ch\t di\u1ec5n\t \u0111\u1ea1t\t b\u1eb1ng\t ti\u00ean\t \u0111\u1ec1\t c\u1ee7a\t n\u00f3\t kh\u00f4ng\t \u0111\u01b0\u1ee3c ph\u00e9p\t g\u00e2y\t \u1ea3o\t gi\u00e1c\t l\u00e0m\t ch\u00fang\t ta\t qu\u00ean\t \u0111i\t ngu\u1ed3n\t g\u1ed1c\t th\u1ef1c\t nghi\u1ec7m c\u1ee7a\tn\u00f3\t(c\u00e1c\tkh\u1ea3\tn\u0103ng\tch\u1ee9a\t\u0111\u1ef1ng,\thay\t\u0111\u1eb7t\tc\u00e1c\tv\u1eadt\tr\u1eafn\tc\u1ea1nh\tnhau). \u0110\u1eb7c\t bi\u1ec7t,\t t\u00ednh\t ch\u1ea5t\t ba\t chi\u1ec1u\t c\u1ee7a\t kh\u00f4ng\t gian,\t c\u0169ng\t nh\u01b0\t \u0111\u1eb7c\t t\u00ednh Euclid\t c\u1ee7a\t n\u00f3\t l\u00e0\t c\u00f3\t ngu\u1ed3n\t g\u1ed1c\t th\u1ef1c\t nghi\u1ec7m\t (n\u00f3\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t l\u1ea5p \u0111\u1ea7y\t to\u00e0n\t b\u1ed9\t b\u1edfi\t nh\u1eefng\t \\\"h\u00ecnh\t l\u1eadp\t ph\u01b0\u01a1ng\\\"\t \u0111\u01b0\u1ee3c\t c\u1ea5u\t t\u1ea1o\t gi\u1ed1ng nhau). T\u00ednh\t tinh\t t\u1ebf\t c\u1ee7a\t kh\u00e1i\t ni\u1ec7m\t kh\u00f4ng\t gian\t \u0111\u01b0\u1ee3c\t n\u00e2ng\t cao\t l\u00ean\t b\u1edfi s\u1ef1\tkh\u00e1m\tph\u00e1\tr\u1eb1ng\tkh\u00f4ng\tc\u00f3\tv\u1eadt\tth\u1ec3\tho\u00e0n\tto\u00e0n\tr\u1eafn.\tT\u1ea5t\tc\u1ea3\tm\u1ecdi\tv\u1eadt th\u1ec3\t \u0111\u1ec1u\t c\u00f3\t th\u1ec3\t bi\u1ebfn\t d\u1ea1ng\t \u0111\u01b0\u1ee3c\t m\u1ed9t\t c\u00e1ch\t \u0111\u00e0n\t h\u1ed3i\t v\u00e0\t thay\t \u0111\u1ed5i\t th\u1ec3 t\u00edch\t c\u1ee7a\t ch\u00fang\t khi\t nhi\u1ec7t\t \u0111\u1ed9\t thay\t \u0111\u1ed5i.\t Cho\t n\u00ean\t c\u00e1c\t h\u00ecnh\t th\u1ec3,\t m\u00e0 kh\u1ea3\tn\u0103ng\tch\u1ee9a\t\u0111\u1ef1ng\tkh\u1ea3\td\u0129\tc\u1ee7a\tch\u00fang\t\u0111\u01b0\u1ee3c\tm\u00f4\tt\u1ea3\tb\u1eb1ng\th\u00ecnh\th\u1ecdc Euclid,\t do\t \u0111\u00f3\t kh\u00f4ng\t th\u1ec3\t \u0111\u01b0\u1ee3c\t quy\t \u0111\u1ecbnh\t tho\u00e1t\t ly\t kh\u1ecfi\t n\u1ed9i\t dung c\u1ee7a\tv\u1eadt\tl\u00fd.\tNh\u01b0ng\tv\u00ec\tv\u1eadt\tl\u00fd\th\u1ecdc,\t\u0111\u1ec3\tthi\u1ebft\tl\u1eadp\tc\u00e1c\tkh\u00e1i\tni\u1ec7m\tc\u1ee7a\tn\u00f3, \u0111\u00e3\tph\u1ea3i\ts\u1eed\td\u1ee5ng\th\u00ecnh\th\u1ecdc,\tn\u00ean\th\u00e0m\tl\u01b0\u1ee3ng\tth\u1ef1c\tnghi\u1ec7m\tc\u1ee7a\th\u00ecnh h\u1ecdc\t ch\u1ec9\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t x\u00e1c\t nh\u1eadn\t v\u00e0\t ki\u1ebfm\t tra\t trong\t khu\u00f4n\t kh\u1ed5\t c\u1ee7a to\u00e0n\tng\u00e0nh\tv\u1eadt\tl\u00fd\th\u1ecdc\tth\u00f4i. Trong\tm\u1ed1i\tli\u00ean\th\u1ec7\tn\u00e0y,\tng\u01b0\u1eddi\tta\tph\u1ea3i\tngh\u0129\t\u0111\u1ebfn\tthuy\u1ebft\tnguy\u00ean t\u1eed,\t v\u00e0\t quan\t \u0111i\u1ec3m\t c\u1ee7a\t n\u00f3\t v\u1ec1\t t\u00ednh\t kh\u1ea3\t ph\u00e2n\t h\u1eefu\t h\u1ea1n\t (chia\t nh\u1ecf \u0111\u01b0\u1ee3c);\tv\u00ec\tkh\u00f4ng\tgian\tc\u1ee7a\ts\u1ef1\tn\u1edbi\tr\u1ed9ng\t\u0111\u1ebfn\tph\u1ea7n\td\u01b0\u1edbi-nguy\u00ean\tt\u1eed\tl\u00e0 kh\u00f4ng\tth\u1ec3\t\u0111o\tl\u01b0\u1eddng\t\u0111\u01b0\u1ee3c.\tThuy\u1ebft\tnguy\u00ean\tt\u1eed\tc\u0169ng\tbu\u1ed9c\tch\u00fang\tta t\u1eeb\tb\u1ecf,\ttr\u00ean\tnguy\u00ean\tt\u1eafc,\t\u00fd\tt\u01b0\u1edfng\tcho\tr\u1eb1ng\tb\u1ec1\tm\u1eb7t\tgi\u1edbi\th\u1ea1n\tc\u1ee7a\tc\u00e1c v\u1eadt\t th\u1ec3\t r\u1eafn\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t x\u00e1c\t \u0111\u1ecbnh\t m\u1ed9t\t c\u00e1ch\t t\u0129nh\t v\u00e0\t s\u1eafc\t n\u00e9t.\t N\u00f3i \u0111\u00fang\tra,\tkh\u00f4ng\tc\u00f3\t\u0111\u1ecbnh\tlu\u1eadt\tri\u00eang\tbi\u1ec7t\tn\u00e0o\tcho\tc\u00e1c\tc\u1ea5u\th\u00ecnh\tkh\u1ea3 d\u0129\tc\u1ee7a\tc\u00e1c\tv\u1eadt\tth\u1ec3\tr\u1eafn\tti\u1ebfp\tx\u00fac\tnhau,\tngay\ttrong\tv\u00f9ng\tv\u0129\tm\u00f4. M\u1eb7c\t d\u00f9\t th\u1ebf,\t kh\u00f4ng\t ai\t ngh\u0129\t c\u1ea7n\t ph\u1ea3i\t t\u1eeb\t b\u1ecf\t kh\u00e1i\t ni\u1ec7m\t kh\u00f4ng gian,\tb\u1edfi\tv\u00ec\tn\u00f3\tt\u1ecf\tra\tkh\u00f4ng\tth\u1ec3\tthi\u1ebfu\ttrong\tto\u00e0n\th\u1ec7\tth\u1ed1ng\t\u0111\u00e3\t\u0111\u01b0\u1ee3c th\u1eed\tth\u00e1ch\tv\u00e0\tth\u00e0nh\tc\u00f4ng\txu\u1ea5t\ts\u1eafc\tc\u1ee7a\tkhoa\th\u1ecdc\tt\u1ef1\tnhi\u00ean.\tMach\tl\u00e0 ng\u01b0\u1eddi\t duy\t nh\u1ea5t\t trong\t th\u1ebf\t k\u1ef7\t XIX\t nghi\u00eam\t t\u00fac\t ngh\u0129\t \u0111\u1ebfn\t vi\u1ec7c\t lo\u1ea1i b\u1ecf\t kh\u00e1i\t ni\u1ec7m\t kh\u00f4ng\t gian,\t b\u1eb1ng\t vi\u1ec7c\t \u00f4ng\t t\u00ecm\t c\u00e1ch\t thay\t th\u1ebf\t n\u00f3 b\u1eb1ng\tkh\u00e1i\tni\u1ec7m\tto\u00e0n\tth\u1ec3\tc\u00e1c\tkho\u1ea3ng\tc\u00e1ch\tc\u00f3\tm\u1eb7t\tc\u1ee7a\tt\u1ea5t\tc\u1ea3\t\u0111i\u1ec3m v\u1eadt\t ch\u1ea5t\t (\u00d4ng\t \u0111\u00e3\t n\u1ed7\t l\u1ef1c\t l\u00e0m\t vi\u1ec7c\t n\u00e0y\t \u0111\u1ec3\t \u0111i\t \u0111\u1ebfn\t m\u1ed9t\t s\u1ef1\t hi\u1ec3u\t bi\u1ebft th\u1ecfa\t\u0111\u00e1ng\tv\u1ec1\tqu\u00e1n\tt\u00ednh). TR\u01af\u1edcNG","Trong\t c\u01a1\t h\u1ecdc\t Newton,\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian\t \u0111\u00f3ng\t m\u1ed9t\t vai tr\u00f2\t \u0111\u00f4i.\t Th\u1ee9\t nh\u1ea5t\t l\u00e0\t vai\t tr\u00f2\t gi\u00e1\t \u0111\u1ee1,\t hay\t khung,\t c\u1ee7a\t c\u00e1c\t di\u1ec5n\t bi\u1ebfn v\u1eadt\tl\u00fd,\tm\u00e0\ttr\u00ean\t\u0111\u00f3\tc\u00e1c\ts\u1ef1\tki\u1ec7n\t\u0111\u01b0\u1ee3c\tm\u00f4\tt\u1ea3\tb\u1eb1ng\tc\u00e1c\tt\u1ecda\t\u0111\u1ed9\tkh\u00f4ng gian\t v\u00e0\t th\u1eddi\t gian.\t Tr\u00ean\t nguy\u00ean\t t\u1eafc,\t v\u1eadt\t ch\u1ea5t\t \u0111\u01b0\u1ee3c\t xem\t nh\u01b0\t c\u1ea5u th\u00e0nh\tb\u1edfi\tnh\u1eefng\t\\\"\u0111i\u1ec3m\tv\u1eadt\tch\u1ea5t\\\"\tm\u00e0\tc\u00e1c\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tch\u00fang l\u00e0m\tn\u00ean\tdi\u1ec5n\tbi\u1ebfn\tv\u1eadt\tl\u00fd.\tN\u1ebfu\tv\u1eadt\tch\u1ea5t\t\u0111\u01b0\u1ee3c\txem\tl\u00e0\tli\u00ean\tt\u1ee5c,\tth\u00ec\tc\u00f3 th\u1ec3\t n\u00f3i,\t \u0111i\u1ec1u\t n\u00e0y\t x\u1ea3y\t ra\t c\u00f3\t th\u1ec3\t n\u00f3i\t nh\u01b0\t nh\u1ea5t\t th\u1eddi\t trong\t nh\u1eefng tr\u01b0\u1eddng\th\u1ee3p\tm\u00e0\t\u1edf\t\u0111\u00f3\tng\u01b0\u1eddi\tta\tkh\u00f4ng\tmu\u1ed1n,\thay\tkh\u00f4ng\tth\u1ec3\tm\u00f4\tt\u1ea3 \u0111\u01b0\u1ee3c\tc\u1ea5u\ttr\u00fac\tr\u1eddi\tr\u1ea1c.\tTrong\ttr\u01b0\u1eddng\th\u1ee3p\tn\u00e0y,\tc\u00e1c\tph\u1ea7n\tnh\u1ecf\t(ph\u1ea7n t\u1eed\tc\u1ee7a\tth\u1ec3\tt\u00edch)\tc\u1ee7a\tv\u1eadt\tch\u1ea5t\t\u0111\u01b0\u1ee3c\txem\tt\u01b0\u01a1ng\tt\u1ef1\tnh\u01b0\tc\u00e1c\t\u0111i\u1ec3m\tv\u1eadt ch\u1ea5t,\t \u00edt\t ra\t trong\t ch\u1eebng\t m\u1ef1c\t ch\u00fang\t ta\t ch\u1ec9\t quan\t t\u00e2m\t \u0111\u1ebfn\t c\u00e1c chuy\u1ec3n\t\u0111\u1ed9ng,\tv\u00e0\tkh\u00f4ng\tquan\tt\u00e2m\t\u0111\u1ebfn\tc\u00e1c\tdi\u1ec5n\tbi\u1ebfn\tm\u00e0\thi\u1ec7n\tth\u1eddi ch\u00fang\t ta\t kh\u00f4ng\t th\u1ec3\t quy\t ch\u00fang\t v\u1ec1\t c\u00e1c\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u01b0\u1ee3c,\t ho\u1eb7c kh\u00f4ng\th\u1eefu\t\u00edch\tkhi\tl\u00e0m\tth\u1ebf\t(th\u00ed\td\u1ee5\tc\u00e1c\tthay\t\u0111\u1ed5i\tnhi\u1ec7t\t\u0111\u1ed9,\tc\u00e1c\tqu\u00e1 tr\u00ecnh\th\u00f3a\th\u1ecdc).\tVai\ttr\u00f2\tth\u1ee9\thai\tc\u1ee7a\tkh\u00f4ng\tgian\tv\u00e0\tth\u1eddi\tgian\tl\u00e0\tvai tr\u00f2\tc\u1ee7a\t\\\"h\u1ec7\tqu\u00e1n\tt\u00ednh\\\"[83].\tTrong\tt\u1ea5t\tc\u1ea3\tc\u00e1c\th\u1ec7\tquy\tchi\u1ebfu\tkh\u1ea3\td\u0129\tth\u00ec c\u00e1c\th\u1ec7\tqu\u00e1n\tt\u00ednh\t\u0111\u01b0\u1ee3c\txem\tl\u00e0\t\u01b0u\t\u0111\u00e3i\tv\u00ec\tl\u00fd\tdo,\t\u0111\u1ed1i\tv\u1edbi\tch\u00fang,\t\u0111\u1ecbnh lu\u1eadt\tqu\u00e1n\tt\u00ednh\tc\u00f3\thi\u1ec7u\tl\u1ef1c. \u0110i\u1ec1u\tc\u1ed1t\tl\u00f5i\t\u1edf\t\u0111\u00e2y\tl\u00e0,\tc\u00e1i\t\\\"th\u1ef1c\tt\u1ea1i\tv\u1eadt\tl\u00fd\\\",\t\u0111\u01b0\u1ee3c\txem\tnh\u01b0\t\u0111\u1ed9c\tl\u1eadp v\u1edbi\tc\u00e1c\tch\u1ee7\tth\u1ec3\ttr\u1ea3i\tnghi\u1ec7m,\t\u0111\u01b0\u1ee3c\tquan\tni\u1ec7m,\t\u00edt\tra\tv\u1ec1\tnguy\u00ean\tt\u1eafc, g\u1ed3m\t c\u00f3\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian\t m\u1ed9t\t b\u00ean,\t v\u00e0\t c\u00e1c\t \u0111i\u1ec3m\t v\u1eadt\t ch\u1ea5t th\u01b0\u1eddng\t xuy\u00ean\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u1ed1i\t v\u1edbi\t ch\u00fang\t b\u00ean\t kia.\t \u00dd\t t\u01b0\u1edfng\t c\u1ee7a s\u1ef1\tt\u1ed3n\tt\u1ea1i\t\u0111\u1ed9c\tl\u1eadp\tc\u1ee7a\tkh\u00f4ng\tgian\tv\u00e0\tth\u1eddi\tgian\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\tdi\u1ec5n\tt\u1ea3 m\u1ed9t\t c\u00e1ch\t ti\u00eau\t bi\u1ec3u\t nh\u01b0\t sau:\t N\u1ebfu\t v\u1eadt\t ch\u1ea5t\t bi\u1ebfn\t m\u1ea5t,\t th\u00ec\t kh\u00f4ng gian\t v\u00e0\t th\u1eddi\t gian\t v\u1eabn\t c\u00f2n\t l\u1ea1i\t m\u1ed9t\t m\u00ecnh\t (nh\u01b0\t m\u1ed9t\t lo\u1ea1i\t s\u00e2n\t kh\u1ea5u cho\tc\u00e1c\tdi\u1ec5n\tbi\u1ebfn\tv\u1eadt\tl\u00fd). S\u1ef1\t kh\u1eafc\t ph\u1ee5c\t quan\t \u0111i\u1ec3m\t n\u00e0y\t \u0111\u00e3\t tho\u00e1t\t thai\t t\u1eeb\t m\u1ed9t\t s\u1ef1\t ph\u00e1t tri\u1ec3n\t tho\u1ea1t\t \u0111\u1ea7u\t c\u00f3\t v\u1ebb\t kh\u00f4ng\t li\u00ean\t quan\t g\u00ec\t \u0111\u1ebfn\t b\u00e0i\t to\u00e1n\t kh\u00f4ng- th\u1eddi-gian\t-\t\u0111\u00f3\tl\u00e0\ts\u1ef1\txu\u1ea5t\thi\u1ec7n\tc\u1ee7a\tkh\u00e1i\tni\u1ec7m\ttr\u01b0\u1eddng\tv\u00e0\ty\u00eau\ts\u00e1ch\tt\u1ed1i h\u1eadu\tc\u1ee7a\tn\u00f3\tl\u00e0\tph\u1ea3i\tthay\t\u0111\u1ed5i,\tv\u1ec1\tnguy\u00ean\tt\u1eafc,\tkh\u00e1i\tni\u1ec7m\th\u1ea1t\t(\u0111i\u1ec3m v\u1eadt\tch\u1ea5t).\tTrong\tkhu\u00f4n\tkh\u1ed5\tv\u1eadt\tl\u00fd\tc\u1ed5\t\u0111i\u1ec3n,\tkh\u00e1i\tni\u1ec7m\ttr\u01b0\u1eddng\txu\u1ea5t hi\u1ec7n\t nh\u01b0\t kh\u00e1i\t ni\u1ec7m\t ph\u1ee5\t tr\u1ee3,\t trong\t nh\u1eefng\t tr\u01b0\u1eddng\t h\u1ee3p\t m\u00e0\t \u1edf\t \u0111\u00f3 ng\u01b0\u1eddi\tta\txem\tv\u1eadt\tch\u1ea5t\tnh\u01b0\tm\u1ed9t\tcontinum\t(m\u00f4i\ttr\u01b0\u1eddng\tli\u00ean\tt\u1ee5c). Th\u00ed\td\u1ee5\tkhi\tng\u01b0\u1eddi\tta\tx\u00e9t\ts\u1ef1\td\u1eabn\tnhi\u1ec7t\ttrong\tm\u1ed9t\tv\u1eadt\tth\u1ec3\tr\u1eafn,\ttr\u1ea1ng th\u00e1i\t c\u1ee7a\t v\u1eadt\t th\u1ec3\t \u0111\u01b0\u1ee3c\t m\u00f4\t t\u1ea3\t b\u1eb1ng\t c\u00e1ch\t cho\t bi\u1ebft\t nhi\u1ec7t\t \u0111\u1ed9\t \u1edf\t m\u1ed7i \u0111i\u1ec3m\tc\u1ee7a\tv\u1eadt\tth\u1ec3\tt\u1ea1i\tm\u1ed7i\tth\u1eddi\tgian\tnh\u1ea5t\t\u0111\u1ecbnh.\tB\u1eb1ng\tto\u00e1n\th\u1ecdc,\t\u0111i\u1ec1u n\u00e0y\tc\u00f3\tngh\u0129a:\tNhi\u1ec7t\t\u0111\u1ed9\tT\t\u0111\u01b0\u1ee3c\tbi\u1ec3u\tdi\u1ec5n\tb\u1eb1ng\tm\u1ed9t\tbi\u1ec3u\tth\u1ee9c\tto\u00e1n","h\u1ecdc\t (h\u00e0m\t s\u1ed1)\t theo\t c\u00e1c\t t\u1ecda\t \u0111\u1ed9\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian\t t\t (tr\u01b0\u1eddng nhi\u1ec7t\t\u0111\u1ed9).\t\u0110\u1ecbnh\tlu\u1eadt\tc\u1ee7a\ts\u1ef1\td\u1eabn\tnhi\u1ec7t\ts\u1ebd\t\u0111\u01b0\u1ee3c\tbi\u1ec3u\tdi\u1ec5n\tb\u1eb1ng\tm\u1ed9t quan\t h\u1ec7\t c\u1ee5c\t b\u1ed9\t (ph\u01b0\u01a1ng\t tr\u00ecnh\t vi\t ph\u00e2n),\t ch\u1ee9a\t \u0111\u1ef1ng\t t\u1ea5t\t c\u1ea3\t c\u00e1c tr\u01b0\u1eddng\t h\u1ee3p\t \u0111\u1eb7c\t bi\u1ec7t\t c\u1ee7a\t s\u1ef1\t d\u1eabn\t nhi\u1ec7t.\t Nhi\u1ec7t\t \u0111\u1ed9\t \u1edf\t \u0111\u00e2y\t l\u00e0\t m\u1ed9t\t th\u00ed d\u1ee5\t\u0111\u01a1n\tgi\u1ea3n\tcho\tkh\u00e1i\tni\u1ec7m\ttr\u01b0\u1eddng.\t\u0110\u1ea1i\tl\u01b0\u1ee3ng\tn\u00e0y\t(hay\tm\u1ed9t\tt\u1ed5ng th\u1ec3\tc\u1ee7a\tc\u00e1c\t\u0111\u1ea1i\tl\u01b0\u1ee3ng)\tl\u00e0\tm\u1ed9t\th\u00e0m\ts\u1ed1\tc\u1ee7a\tc\u00e1c\tt\u1ecda\t\u0111\u1ed9\tv\u00e0\tth\u1eddi\tgian. M\u1ed9t\tth\u00ed\td\u1ee5\tkh\u00e1c\tl\u00e0\ts\u1ef1\tm\u00f4\tt\u1ea3\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tm\u1ed9t\tch\u1ea5t\tl\u1ecfng.\tT\u1ea1i m\u1ed7i\t \u0111i\u1ec3m,\t c\u00f3\t m\u1ed9t\t v\u1eadn\t t\u1ed1c\t \u1edf\t m\u1ed7i\t l\u00fac,\t \u0111\u01b0\u1ee3c\t di\u1ec5n\t t\u1ea3\t \u0111\u1ecbnh\t l\u01b0\u1ee3ng b\u1eb1ng\t ba\t \\\"th\u00e0nh\t ph\u1ea7n\\\"\t c\u1ee7a\t n\u00f3\t \u0111\u1ed1i\t v\u1edbi\t c\u00e1c\t tr\u1ee5c\t c\u1ee7a\t m\u1ed9t\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9 (vect\u01a1).\t C\u00e1c\t th\u00e0nh\t ph\u1ea7n\t c\u1ee7a\t v\u1eadn\t t\u1ed1c\t t\u1ea1i\t m\u1ed9t\t \u0111i\u1ec3m\t (c\u00e1c\t th\u00e0nh ph\u1ea7n\ttr\u01b0\u1eddng),\t\u1edf\t\u0111\u00e2y\tc\u0169ng\tth\u1ebf,\tl\u00e0\tnh\u1eefng\th\u00e0m\ts\u1ed1\tc\u1ee7a\tt\u1ecda\t\u0111\u1ed9\t(x,\ty,\tz) v\u00e0\tth\u1eddi\tgian\t(t). \u0110\u1eb7c\t tr\u01b0ng\t cho\t nh\u1eefng\t tr\u01b0\u1eddng\t \u0111\u01b0\u1ee3c\t n\u00f3i\t tr\u00ean\t l\u00e0\t ch\u00fang\t ch\u1ec9\t di\u1ec5n ra\tb\u00ean\ttrong\tm\u1ed9t\tkh\u1ed1i\tl\u01b0\u1ee3ng\tc\u00f3\ttr\u1ecdng\tl\u01b0\u1ee3ng;\tch\u00fang\tch\u1ec9\t\u0111\u1ec3\tm\u00f4\tt\u1ea3 tr\u1ea1ng\tth\u00e1i\tc\u1ee7a\tkh\u1ed1i\tv\u1eadt\tch\u1ea5t\tn\u00e0y. \u1ede\t \u0111\u00e2u\t kh\u00f4ng\t c\u00f3\t v\u1eadt\t ch\u1ea5t,\t theo\t l\u1ecbch\t s\u1eed\t h\u00ecnh\t th\u00e0nh\t c\u1ee7a\t kh\u00e1i ni\u1ec7m\t tr\u01b0\u1eddng,\t \u1edf\t \u0111\u00f3\t c\u0169ng\t kh\u00f4ng\t th\u1ec3\t c\u00f3\t tr\u01b0\u1eddng\t t\u1ed3n\t t\u1ea1i.\t Nh\u01b0ng trong\t ph\u1ea7n\t t\u01b0\t \u0111\u1ea7u\t th\u1ebf\t k\u1ef7\t XIX\t ng\u01b0\u1eddi\t ta\t \u0111\u00e3\t th\u1ea5y\t c\u00e1c\t hi\u1ec7n\t t\u01b0\u1ee3ng giao\t thoa\t v\u00e0\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t \u00e1nh\t s\u00e1ng\t \u0111\u01b0\u1ee3c\t c\u1eaft\t ngh\u0129a\t v\u1edbi\t \u0111\u1ed9 ch\u00ednh\t x\u00e1c\t \u0111\u00e1ng\t ng\u1ea1c\t nhi\u00ean\t n\u1ebfu\t ng\u01b0\u1eddi\t ta\t quan\t ni\u1ec7m\t \u00e1nh\t s\u00e1ng nh\u01b0\tm\u1ed9t\ttr\u01b0\u1eddng\ts\u00f3ng,\tho\u00e0n\tto\u00e0n\tt\u01b0\u01a1ng\tt\u1ef1\tv\u1edbi\ttr\u01b0\u1eddng\trung\t\u0111\u1ed9ng c\u01a1\t h\u1ecdc\t trong\t m\u1ed9t\t v\u1eadt\t th\u1ec3\t r\u1eafn\t \u0111\u00e0n\t h\u1ed3i.\t Do\t \u0111\u00f3\t ng\u01b0\u1eddi\t ta\t th\u1ea5y\t c\u1ea7n thi\u1ebft\t ph\u1ea3i\t t\u1ea1o\t ra\t kh\u00e1i\t ni\u1ec7m\t tr\u01b0\u1eddng,\t c\u0169ng\t c\u00f3\t th\u1ec3\t t\u1ed3n\t t\u1ea1i\t trong \\\"kh\u00f4ng\tgian\tr\u1ed7ng\\\"\tkh\u00f4ng\tch\u1ee9a\tv\u1eadt\tch\u1ea5t\tc\u00f3\ttr\u1ecdng\tl\u01b0\u1ee3ng. Ho\u00e0n\t c\u1ea3nh\t n\u00e0y\t t\u1ea1o\t ra\t m\u1ed9t\t t\u00ecnh\t hu\u1ed1ng\t m\u00e2u\t thu\u1eabn,\t v\u00ec\t kh\u00e1i ni\u1ec7m\ttr\u01b0\u1eddng\tban\t\u0111\u1ea7u\txu\u1ea5t\thi\u1ec7n\tch\u1ec9\t\u0111\u1ec3\tm\u00f4\tt\u1ea3\tc\u00e1c\ttr\u1ea1ng\tth\u00e1i\t\u1edf\tb\u00ean trong\t c\u1ee7a\t m\u1ed9t\t v\u1eadt\t th\u1ec3\t c\u00f3\t tr\u1ecdng\t l\u01b0\u1ee3ng.\t \u0110i\u1ec1u\t n\u00e0y\t l\u1ea1i\t c\u00e0ng\t hi\u1ec7n\t ra ch\u1eafc\tch\u1eafn\th\u01a1n\tkhi\tng\u01b0\u1eddi\tta\ttin\tr\u1eb1ng\tm\u1ed7i\ttr\u01b0\u1eddng\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\txem l\u00e0\tm\u1ed9t\ttr\u1ea1ng\tth\u00e1i\tc\u00f3\tth\u1ec3\tdi\u1ec5n\tgi\u1ea3i\t\u0111\u01b0\u1ee3c\tm\u1ed9t\tc\u00e1ch\tc\u01a1\th\u1ecdc,\t\u0111i\u1ec1u\tgi\u1ea3 \u0111\u1ecbnh\ts\u1ef1\thi\u1ec7n\tdi\u1ec7n\tc\u1ee7a\tv\u1eadt\tch\u1ea5t.\tV\u00ec\tth\u1ebf\tng\u01b0\u1eddi\tta\tc\u1ea3m\tth\u1ea5y\tb\u1eaft\tbu\u1ed9c gia\tthi\u1ebft\ts\u1ef1\tt\u1ed3n\tt\u1ea1i\t\u1edf\tkh\u1eafp\tn\u01a1i\tc\u1ee7a\tm\u1ed9t\tlo\u1ea1i\tv\u1eadt\tch\u1ea5t\tm\u00e0\tng\u01b0\u1eddi\tta g\u1ecdi\t l\u00e0\t \\\"ether\\\",\t ngay\t c\u1ea3\t trong\t kh\u00f4ng\t gian\t cho\t \u0111\u1ebfn\t nay\t \u0111\u01b0\u1ee3c\t quan ni\u1ec7m\tr\u1ed7ng. S\u1ef1\t gi\u1ea3i\t ph\u00f3ng\t kh\u00e1i\t ni\u1ec7m\t tr\u01b0\u1eddng\t ra\t kh\u1ecfi\t gi\u1ea3\t thuy\u1ebft\t v\u1ec1\t s\u1ef1\t t\u1ed3n t\u1ea1i\tc\u1ee7a\tm\u1ed9t\tm\u00f4i\ttr\u01b0\u1eddng\tn\u1ec1n\tb\u1eb1ng\tv\u1eadt\tch\u1ea5t\tl\u00e0\tm\u1ed9t\ttrong\tnh\u1eefng\ts\u1ef1 ki\u1ec7n\t v\u1ec1\t m\u1eb7t\t t\u00e2m\t l\u00fd\t th\u00fa\t v\u1ecb\t nh\u1ea5t\t c\u1ee7a\t s\u1ef1\t ph\u00e1t\t tri\u1ec3n\t t\u01b0\t duy\t v\u1eadt\t l\u00fd. Trong\tn\u1eeda\tph\u1ea7n\tsau\tc\u1ee7a\tth\u1ebf\tk\u1ef7\tXIX,\td\u1ef1a\tv\u00e0o\tc\u00e1c\tnghi\u00ean\tc\u1ee9u\tc\u1ee7a","Faraday\t v\u00e0\t Maxwell,\t ng\u01b0\u1eddi\t ta\t th\u1ea5y\t c\u00e0ng\t ng\u00e0y\t c\u00e0ng\t r\u00f5\t h\u01a1n,\t r\u1eb1ng s\u1ef1\tm\u00f4\tt\u1ea3\tb\u1eb1ng\ttr\u01b0\u1eddng\tc\u00e1c\tqu\u00e1\ttr\u00ecnh\t\u0111i\u1ec7n\tt\u1eeb\tc\u00f3\tt\u00ednh\t\u01b0u\tvi\u1ec7t\th\u1eb3n\tso v\u1edbi\t s\u1ef1\t m\u00f4\t t\u1ea3\t d\u1ef1a\t tr\u00ean\t c\u01a1\t s\u1edf\t c\u00e1c\t kh\u00e1i\t ni\u1ec7m\t c\u01a1\t h\u1ecdc\t c\u1ee7a\t \u0111i\u1ec3m\t v\u1eadt ch\u1ea5t.\t B\u1eb1ng\t vi\u1ec7c\t \u0111\u01b0a\t kh\u00e1i\t ni\u1ec7m\t tr\u01b0\u1eddng\t v\u00e0o\t \u0111\u1ed9ng\t \u0111i\u1ec7n\t h\u1ecdc, Maxwell\t \u0111\u00e3\t th\u00e0nh\t c\u00f4ng\t trong\t vi\u1ec7c\t ti\u00ean\t \u0111o\u00e1n\t s\u1ef1\t t\u1ed3n\t t\u1ea1i\t c\u1ee7a\t s\u00f3ng \u0111i\u1ec7n\tt\u1eeb\tm\u00e0\ts\u1ef1\tt\u01b0\u01a1ng\t\u0111\u1ed3ng\tc\u1ed1t\tl\u00f5i\tc\u1ee7a\tn\u00f3\tv\u1edbi\ts\u00f3ng\t\u00e1nh\ts\u00e1ng\tkh\u00f4ng c\u00f2n\t nghi\t ng\u1edd\t g\u00ec\t n\u1eefa\t b\u1edfi\t v\u1eadn\t t\u1ed1c\t truy\u1ec1n\t c\u1ee7a\t ch\u00fang\t b\u1eb1ng\t nhau. B\u1eb1ng\tc\u00e1ch\t\u0111\u00f3\tquang\th\u1ecdc\tv\u1ec1\tc\u01a1\tb\u1ea3n\tb\u1ecb\th\u1ea5p\tth\u1ee5\tv\u00e0o\t\u0111i\u1ec7n\t\u0111\u1ed9ng\th\u1ecdc. M\u1ed9t\t hi\u1ec7u\t \u1ee9ng\t t\u00e2m\t l\u00fd\t c\u1ee7a\t th\u00e0nh\t c\u00f4ng\t v\u0129\t \u0111\u1ea1i\t n\u00e0y\t l\u00e0\t kh\u00e1i\t ni\u1ec7m tr\u01b0\u1eddng\t d\u1ea7n\t d\u1ea7n\t gi\u00e0nh\t \u0111\u01b0\u1ee3c\t s\u1ef1\t \u0111\u1ed9c\t l\u1eadp\t l\u1edbn\t h\u01a1n\t tr\u01b0\u1edbc\t khu\u00f4n\t kh\u1ed5 c\u01a1\tgi\u1edbi\tc\u1ee7a\tv\u1eadt\tl\u00fd\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n. Nh\u01b0ng\t r\u1ed3i\t l\u00fac\t \u0111\u1ea7u\t ng\u01b0\u1eddi\t ta\t v\u1eabn\t ti\u1ebfp\t t\u1ee5c\t gi\u1ea3\t thi\u1ebft\t nh\u01b0\t m\u1ed9t\t l\u1ebd \u0111\u01b0\u01a1ng\t nhi\u00ean,\t r\u1eb1ng\t c\u00e1c\t tr\u01b0\u1eddng\t \u0111i\u1ec7n\t t\u1eeb\t ph\u1ea3i\t \u0111\u01b0\u1ee3c\t l\u00fd\t gi\u1ea3i\t nh\u01b0\t c\u00e1c tr\u1ea1ng\t th\u00e1i\t c\u1ee7a\t ether,\t v\u00e0\t ng\u01b0\u1eddi\t ta\t \u0111i\t t\u00ecm\t c\u00e1c\t tr\u1ea1ng\t th\u00e1i\t n\u00e0y\t m\u1ed9t c\u00e1ch\th\u0103ng\tsay\tnh\u01b0\tl\u00e0\tnh\u1eefng\ttr\u1ea1ng\tth\u00e1i\tc\u01a1\th\u1ecdc.\tCh\u1ec9\tkhi\tnh\u1eefng\tn\u1ed7 l\u1ef1c\t n\u00e0y\t li\u00ean\t ti\u1ebfp\t th\u1ea5t\t b\u1ea1i,\t c\u00e1c\t nh\u00e0\t khoa\t h\u1ecdc\t m\u1edbi\t d\u1ea7n\t d\u1ea7n\t l\u00e0m quen\tv\u1edbi\tquan\t\u0111i\u1ec3m\tt\u1eeb\tch\u1ed1i\tm\u1ed9t\ts\u1ef1\tl\u00fd\tgi\u1ea3i\tc\u01a1\th\u1ecdc\tnh\u01b0\tth\u1ebf.\tNh\u01b0ng ni\u1ec1m\ttin\tv\u1eabn\tc\u00f2n\tlu\u00f4n\tv\u01b0\u01a1ng\tv\u1ea5n,\tr\u1eb1ng\tc\u00e1c\ttr\u01b0\u1eddng\t\u0111i\u1ec7n\tt\u1eeb\tph\u1ea3i\tl\u00e0 nh\u1eefng\ttr\u1ea1ng\tth\u00e1i\tc\u1ee7a\tether;\tv\u00e0\t\u0111\u00f3\tl\u00e0\tt\u00ecnh\th\u00ecnh\tv\u00e0o\tgiai\t\u0111o\u1ea1n\tgiao th\u1eddi\tc\u1ee7a\tth\u1ebf\tk\u1ef7. Thuy\u1ebft\tether\t\u0111\u00e3\tmang\ttheo\tm\u00ecnh\tc\u00e2u\th\u1ecfi:\tEther\tv\u1eadn\th\u00e0nh\tnh\u01b0 th\u1ebf\t n\u00e0o\t t\u1eeb\t quan\t \u0111i\u1ec3m\t c\u01a1\t h\u1ecdc\t \u0111\u1ed1i\t v\u1edbi\t c\u00e1c\t v\u1eadt\t th\u1ec3\t c\u00f3\t tr\u1ecdng\t l\u01b0\u1ee3ng? N\u00f3\ttham\tgia\tv\u00e0o\tc\u00e1c\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tv\u1eadt\tth\u1ec3,\thay\tl\u00e0\tc\u00e1c\tb\u1ed9\tph\u1eadn c\u1ee7a\t n\u00f3\t \u0111\u1ee9ng\t y\u00ean\t v\u1edbi\t nhau?\t Nhi\u1ec1u\t th\u00ed\t nghi\u1ec7m\t tinh\t vi\t \u0111\u01b0\u1ee3c\t ti\u1ebfn h\u00e0nh\t \u0111\u1ec3\t quy\u1ebft\t \u0111\u1ecbnh\t c\u00e2u\t tr\u1ea3\t l\u1eddi.\t Nh\u1eefng\t s\u1ef1\t ki\u1ec7n\t quan\t tr\u1ecdng\t \u0111\u00e1ng \u0111\u01b0\u1ee3c\t nh\u1eafc\t \u0111\u1ebfn\t trong\t khung\t c\u1ea3nh\t n\u00e0y,\t \u0111\u00f3\t l\u00e0\t \\\"quang\t sai\\\"\t c\u1ee7a\t c\u00e1c sao\tc\u1ed1\t\u0111\u1ecbnh\tnh\u01b0\th\u1ec7\tqu\u1ea3\tc\u1ee7a\ts\u1ef1\tchuy\u1ec3n\t\u0111\u1ed9ng\tth\u01b0\u1eddng\tni\u00ean\tc\u1ee7a\ttr\u00e1i \u0111\u1ea5t,\t c\u0169ng\t nh\u01b0\t \\\"hi\u1ec7u\t \u1ee9ng\t Doppler\\\",\t ngh\u0129a\t l\u00e0\t \u1ea3nh\t h\u01b0\u1edfng\t c\u1ee7a chuy\u1ec3n\t \u0111\u1ed9ng\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t c\u1ee7a\t c\u00e1c\t sao\t c\u1ed1\t \u0111\u1ecbnh\t l\u00ean\t t\u1ea7n\t s\u1ed1\t c\u1ee7a\t \u00e1nh s\u00e1ng\t \u0111\u1ebfn\t m\u1eaft\t ch\u00fang\t ta\t c\u00f3\t c\u00e1c\t t\u1ea7n\t s\u1ed1\t ph\u00e1t\t ra\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t bi\u1ebft\t tr\u01b0\u1edbc. K\u1ebft\t qu\u1ea3\t c\u1ee7a\t nh\u1eefng\t s\u1ef1\t ki\u1ec7n\t v\u00e0\t th\u00ed\t nghi\u1ec7m\t n\u00e0y\t (tr\u1eeb\t k\u1ebft\t qu\u1ea3\t c\u1ee7a m\u1ed9t\tth\u00ed\tnghi\u1ec7m,\tth\u00ed\tnghi\u1ec7m\tMichelson-Morley)\t\u0111\u01b0\u1ee3c\tH.A.\tLorentz gi\u1ea3i\t th\u00edch\t d\u01b0\u1edbi\t s\u1ef1\t gi\u1ea3\t \u0111\u1ecbnh,\t r\u1eb1ng\t ether\t kh\u00f4ng\t tham\t gia\t v\u00e0o chuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tc\u00e1c\tv\u1eadt\tth\u1ec3\tc\u00f3\ttr\u1ecdng\tl\u01b0\u1ee3ng,\tv\u00e0\tc\u00e1c\tb\u1ed9\tph\u1eadn\tc\u1ee7a ether\t ho\u00e0n\t to\u00e0n\t kh\u00f4ng\t c\u00f3\t chuy\u1ec3n\t \u0111\u1ed9ng\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t v\u1edbi\t nhau.\t Do \u0111\u00f3\tether\tc\u00f3\tth\u1ec3\tn\u00f3i\txu\u1ea5t\thi\u1ec7n\tnh\u01b0\tbi\u1ec3u\tt\u01b0\u1ee3ng\tc\u1ee7a\tm\u1ed9t\tkh\u00f4ng\tgian tuy\u1ec7t\t \u0111\u1ed1i\t y\u00ean\t t\u0129nh.\t Nh\u01b0ng\t nghi\u00ean\t c\u1ee9u\t c\u1ee7a\t Lorentz\t c\u00f2n\t \u0111em\t l\u1ea1i nhi\u1ec1u\th\u01a1n.\tN\u00f3\tgi\u1ea3i\tth\u00edch\t\u0111\u01b0\u1ee3c\tc\u00e1c\thi\u1ec7n\tt\u01b0\u1ee3ng\t\u0111i\u1ec7n\tt\u1eeb\thay\tquang","h\u1ecdc\t\u0111\u01b0\u1ee3c\tbi\u1ebft\ttr\u01b0\u1edbc\tcho\t\u0111\u1ebfn\tnay\tdi\u1ec5n\tra\tb\u00ean\ttrong\tc\u00e1c\tv\u1eadt\tth\u1ec3\tc\u00f3 tr\u1ecdng\t l\u01b0\u1ee3ng,\t d\u01b0\u1edbi\t s\u1ef1\t gi\u1ea3\t \u0111\u1ecbnh\t r\u1eb1ng\t \u1ea3nh\t h\u01b0\u1edfng\t c\u1ee7a\t v\u1eadt\t ch\u1ea5t\t c\u00f3 tr\u1ecdng\tl\u01b0\u1ee3ng\tl\u00ean\ttr\u01b0\u1eddng\t\u0111i\u1ec7n\t-\tv\u00e0\tng\u01b0\u1ee3c\tl\u1ea1i\t-\tl\u00e0\tch\u1ec9\tdo\tc\u00e1c\th\u1ea1t\tc\u1ee7a v\u1eadt\t ch\u1ea5t\t mang\t c\u00e1c\t \u0111i\u1ec7n\t t\u00edch,\t v\u00e0\t c\u00e1c\t \u0111i\u1ec7n\t t\u00edch\t n\u00e0y\t tham\t gia\t v\u00e0o chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t c\u00e1c\t h\u1ea1t.\t V\u1ec1\t th\u00ed\t nghi\u1ec7m\t c\u1ee7a\t Michelson-Morley, H.A.\tLorentz\t\u0111\u00e3\tch\u1ee9ng\tminh\tr\u1eb1ng\tk\u1ebft\tqu\u1ea3\tthu\tl\u01b0\u1ee3m\t\u0111\u01b0\u1ee3c\tc\u1ee7a\t\u00f4ng \u00edt\tra\tkh\u00f4ng\tm\u00e2u\tthu\u1eabn\tv\u1edbi\tthuy\u1ebft\tether\t\u0111\u1ee9ng\ty\u00ean. M\u1eb7c\t d\u00f9\t c\u00f3\t t\u1ea5t\t c\u1ea3\t nh\u1eefng\t th\u00e0nh\t c\u00f4ng\t t\u1ed1t\t \u0111\u1eb9p\t n\u00e0y,\t nh\u01b0ng\t hi\u1ec7n tr\u1ea1ng\tc\u1ee7a\tl\u00fd\tthuy\u1ebft\tch\u01b0a\tl\u00e0m\tng\u01b0\u1eddi\tta\th\u00e0i\tl\u00f2ng\tho\u00e0n\tto\u00e0n,\tb\u1edfi\tl\u00fd do\t sau.\t C\u01a1\t h\u1ecdc\t c\u1ed5\t \u0111i\u1ec3n,\t thuy\u1ebft\t m\u00e0\t ch\u00fang\t ta\t kh\u00f4ng\t nghi\t ng\u1edd\t g\u00ec n\u1eefa\t r\u1eb1ng\t n\u00f3\t \u0111\u00fang\t v\u1edbi\t \u0111\u1ed9\t ch\u00ednh\t x\u00e1c\t l\u1edbn,\t d\u1ea1y\t ch\u00fang\t ta\t s\u1ef1\t t\u01b0\u01a1ng \u0111\u01b0\u01a1ng\tc\u1ee7a\tt\u1ea5t\tc\u1ea3\tc\u00e1c\th\u1ec7\tqu\u00e1n\tt\u00ednh,\thay\tc\u00e1c\tkh\u00f4ng\tgian\tqu\u00e1n\tt\u00ednh, trong\t vi\u1ec7c\t di\u1ec5n\t t\u1ea3\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1\t nhi\u00ean,\t ngh\u0129a\t l\u00e0\t t\u00ednh\t b\u1ea5t\t bi\u1ebfn c\u1ee7a\tc\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tt\u1ef1\tnhi\u00ean\t\u0111\u1ed1i\tv\u1edbi\ts\u1ef1\tchuy\u1ec3n\t\u0111\u1ed5i\tt\u1eeb\tm\u1ed9t\th\u1ec7\tqu\u00e1n t\u00ednh\t n\u00e0y\t sang\t h\u1ec7\t kh\u00e1c.\t C\u00e1c\t th\u00ed\t nghi\u1ec7m\t \u0111i\u1ec7n\t t\u1eeb\t h\u1ecdc\t v\u00e0\t quang\t h\u1ecdc d\u1ea1y\tch\u00fang\tta\tc\u00f9ng\tm\u1ed9t\t\u0111i\u1ec1u\tv\u1edbi\t\u0111\u1ed9\tch\u00ednh\tx\u00e1c\t\u0111\u00e1ng\tk\u1ec3.\tNh\u01b0ng\tc\u01a1 s\u1edf\tc\u1ee7a\tthuy\u1ebft\t\u0111i\u1ec7n\tt\u1eeb\tl\u1ea1i\td\u1ea1y\tta\tr\u1eb1ng\tc\u00f3\tm\u1ed9t\th\u1ec7\tqu\u00e1n\tt\u00ednh\t\u0111\u1eb7c\tbi\u1ec7t t\u1ed3n\t t\u1ea1i\t \u0111\u01b0\u1ee3c\t \u01b0u\t \u0111\u00e3i,\t \u0111\u00f3\t l\u00e0\t h\u1ec7\t c\u1ee7a\t ether\t \u00e1nh\t s\u00e1ng[84]\t \u0111\u1ee9ng\t y\u00ean. Quan\t ni\u1ec7m\t n\u00e0y\t c\u1ee7a\t c\u01a1\t s\u1edf\t l\u00fd\t thuy\u1ebft\t l\u00e0\t r\u1ea5t\t kh\u00f4ng\t th\u1ecfa\t \u0111\u00e1ng. Kh\u00f4ng\t c\u00f3\t m\u1ed9t\t s\u1ef1\t c\u1ea3i\t bi\u00ean\t c\u1ee7a\t c\u01a1\t s\u1edf\t l\u00fd\t thuy\u1ebft\t \u0111\u1ec3\t -\t nh\u01b0\t c\u01a1\t h\u1ecdc\t c\u1ed5 \u0111i\u1ec3n\t -\t \u0111\u1ea3m\t b\u1ea3o\t \u0111\u01b0\u1ee3c\t s\u1ef1\t t\u01b0\u01a1ng\t \u0111\u01b0\u01a1ng\t c\u1ee7a\t c\u00e1c\t h\u1ec7\t qu\u00e1n\t t\u00ednh (nguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p)\thay\tsao? C\u00e2u\t tr\u1ea3\t l\u1eddi\t cho\t c\u00e2u\t h\u1ecfi\t n\u00e0y\t ch\u00ednh\t l\u00e0\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p. Thuy\u1ebft\t n\u00e0y\t ti\u1ebfp\t nh\u1eadn\t t\u1eeb\t thuy\u1ebft\t Maxwell-Lorentz\t gi\u1ea3\t thuy\u1ebft\t v\u1ec1 t\u00ednh\th\u1eb1ng\ts\u1ed1\tc\u1ee7a\tv\u1eadn\tt\u1ed1c\t\u00e1nh\ts\u00e1ng\ttrong\tkh\u00f4ng\tgian\tr\u1ed7ng.\t\u0110\u1ec3\tl\u00e0m t\u00ednh\tch\u1ea5t\tn\u00e0y\th\u00f2a\th\u1ee3p\tv\u1edbi\tt\u00ednh\tt\u01b0\u01a1ng\t\u0111\u01b0\u01a1ng\tc\u1ee7a\tc\u00e1c\th\u1ec7\tqu\u00e1n\tt\u00ednh (nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p)\t ch\u00fang\t ta\t ph\u1ea3i\t t\u1eeb\t b\u1ecf\t \u00fd\t t\u01b0\u1edfng\t v\u1ec1\t t\u00ednh tuy\u1ec7t\t \u0111\u1ed1i\t c\u1ee7a\t t\u00ednh\t \u0111\u1ed3ng\t th\u1eddi;\t th\u00eam\t v\u00e0o\t \u0111\u00f3,\t c\u00e1c\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i Lorentz\t c\u1ee7a\t th\u1eddi\t gian\t v\u00e0\t t\u1ecda\t \u0111\u1ed9\t kh\u00f4ng\t gian\t l\u00e0\t h\u1ec7\t lu\u1eadn\t cho\t s\u1ef1 chuy\u1ec3n\t \u0111\u1ed5i\t t\u1eeb\t m\u1ed9t\t h\u1ec7\t qu\u00e1n\t t\u00ednh\t sang\t h\u1ec7\t qu\u00e1n\t t\u00ednh\t kh\u00e1c.\t C\u1ea3\t n\u1ed9i dung\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p\t \u0111\u01b0\u1ee3c\t ch\u1ee9a\t \u0111\u1ef1ng\t trong\t \u0111\u1ecbnh\t \u0111\u1ec1 n\u00e0y:\t C\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1\t nhi\u00ean\t l\u00e0\t b\u1ea5t\t bi\u1ebfn\t \u0111\u1ed1i\t v\u1edbi\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i Lorentz.\t\u0110i\u1ec1u\tquan\ttr\u1ecdng\tnh\u1ea5t\tc\u1ee7a\ty\u00eau\tc\u1ea7u\tn\u00e0y\tn\u1eb1m\t\u1edf\tch\u1ed7\tn\u00f3\tgi\u1edbi h\u1ea1n\tl\u1ea1i,\tm\u1ed9t\tc\u00e1ch\tnh\u1ea5t\t\u0111\u1ecbnh,\tc\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tt\u1ef1\tnhi\u00ean\tc\u00f3\tth\u1ec3\tt\u1ed3n\tt\u1ea1i. \u0110\u00e2u\t l\u00e0\t v\u1ecb\t tr\u00ed\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p\t \u0111\u1ed1i\t v\u1edbi\t b\u00e0i\t to\u00e1n\t v\u1ec1 kh\u00f4ng\t gian?\t Tr\u01b0\u1edbc\t h\u1ebft\t ch\u00fang\t ta\t ph\u1ea3i\t c\u1ea9n\t th\u1eadn\t tr\u01b0\u1edbc\t \u00fd\t ki\u1ebfn\t cho r\u1eb1ng\tt\u00ednh\tch\u1ea5t\tb\u1ed1n\tchi\u1ec1u\tc\u1ee7a\t(th\u1ebf\tgi\u1edbi)\tth\u1ef1c\tt\u1ea1i\tl\u00e0\tch\u1ec9\tm\u1edbi\t\u0111\u01b0\u1ee3c\t\u0111\u1ec1","c\u1eadp\tg\u1ea7n\t\u0111\u00e2y\tb\u1edfi\tl\u00fd\tthuy\u1ebft\tn\u00e0y.\tNgay\ttrong\tc\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n,\ts\u1ef1\tki\u1ec7n c\u0169ng\t\u0111\u01b0\u1ee3c\t\u0111\u1ecbnh\tv\u1ecb\tb\u1eb1ng\tb\u1ed1n\ts\u1ed1,\tc\u1ee5\tth\u1ec3\tl\u00e0\tba\tt\u1ecda\t\u0111\u1ed9\tkh\u00f4ng\tgian\tv\u00e0 m\u1ed9t\tt\u1ecda\t\u0111\u1ed9\tth\u1eddi\tgian;\tto\u00e0n\tth\u1ec3\tc\u00e1c\t\\\"s\u1ef1\tki\u1ec7n\\\"\tv\u1eadt\tl\u00fd\tdo\t\u0111\u00f3\t\u0111\u01b0\u1ee3c\t\u0111\u1eb7t v\u00e0o\tm\u1ed9t\t\u0111a\tt\u1ea1p\tli\u00ean\tt\u1ee5c\tb\u1ed1n\tchi\u1ec1u.\tNh\u01b0ng\ttr\u00ean\tc\u01a1\ts\u1edf\tc\u1ee7a\tc\u01a1\th\u1ecdc\tc\u1ed5 \u0111i\u1ec3n,\tcontinum\tb\u1ed1n\tchi\u1ec1u\tn\u00e0y\t\u0111\u01b0\u1ee3c\tph\u00e2n\tgi\u1ea3i[85]\tm\u1ed9t\tc\u00e1ch\tkh\u00e1ch quan\t th\u00e0nh\t th\u1eddi\t gian\t m\u1ed9t\t chi\u1ec1u\t v\u00e0\t c\u00e1c\t l\u00e1t\t c\u1eaft\t kh\u00f4ng\t gian\t ba chi\u1ec1u,\t nh\u1eefng\t c\u00e1i\t sau\t ch\u1ec9\t ch\u1ee9a\t \u0111\u1ef1ng\t nh\u1eefng\t s\u1ef1\t ki\u1ec7n\t \u0111\u1ed3ng\t th\u1eddi th\u00f4i.\tS\u1ef1\tph\u00e2n\tgi\u1ea3i\tn\u00e0y\tl\u00e0\tgi\u1ed1ng\tnhau\tcho\tt\u1ea5t\tc\u1ea3\tc\u00e1c\th\u1ec7\tqu\u00e1n\tt\u00ednh. T\u00ednh\t \u0111\u1ed3ng\t th\u1eddi\t c\u1ee7a\t hai\t s\u1ef1\t ki\u1ec7n\t nh\u1ea5t\t \u0111\u1ecbnh\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed9t\t h\u1ec7\t qu\u00e1n t\u00ednh\tk\u00e9o\ttheo\tt\u00ednh\t\u0111\u1ed3ng\tth\u1eddi\tc\u1ee7a\tc\u00e1c\ts\u1ef1\tki\u1ec7n\tn\u00e0y\t\u0111\u1ed1i\tv\u1edbi\tt\u1ea5t\tc\u1ea3\tc\u00e1c h\u1ec7\tqu\u00e1n\tt\u00ednh.\t\u0110\u00f3\tl\u00e0\t\u0111i\u1ec1u\t\u0111\u01b0\u1ee3c\thi\u1ec3u\tkhi\tng\u01b0\u1eddi\tta\tn\u00f3i,\tth\u1eddi\tgian\tc\u1ee7a c\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n\tl\u00e0\ttuy\u1ec7t\t\u0111\u1ed1i.\tNh\u01b0ng\ttheo\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p\tth\u00ec t\u00ecnh\th\u00ecnh\tkh\u00e1c\t\u0111i.\tTo\u00e0n\tb\u1ed9\tc\u00e1c\ts\u1ef1\tki\u1ec7n\t\u0111\u1ed3ng\tth\u1eddi\tv\u1edbi\tm\u1ed9t\ts\u1ef1\tki\u1ec7n \u0111\u01b0\u1ee3c\t cho\t tr\u01b0\u1edbc\t tuy\t \u0111\u00fang\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed9t\t h\u1ec7\t qu\u00e1n\t t\u00ednh\t nh\u1ea5t\t \u0111\u1ecbnh, nh\u01b0ng\t kh\u00f4ng\t c\u00f2n\t \u0111\u1ed9c\t l\u1eadp\t n\u1eefa\t \u0111\u1ed1i\t v\u1edbi\t s\u1ef1\t l\u1ef1a\t ch\u1ecdn\t h\u1ec7\t qu\u00e1n\t t\u00ednh. Continum\tb\u1ed1n\tchi\u1ec1u\t kh\u00f4ng\tth\u1ec3\t ph\u00e2n\tgi\u1ea3i\t\u0111\u01b0\u1ee3c\t m\u1ed9t\tc\u00e1ch\t kh\u00e1ch quan\t th\u00e0nh\t c\u00e1c\t l\u00e1t\t c\u1eaft\t ch\u1ee9a\t \u0111\u1ef1ng\t t\u1ea5t\t c\u1ea3\t c\u00e1c\t s\u1ef1\t ki\u1ec7n\t \u0111\u1ed3ng\t th\u1eddi n\u1eefa;\t kh\u00e1i\t ni\u1ec7m\t \\\"b\u00e2y\t gi\u1edd\\\"\t m\u1ea5t\t \u0111i\t \u00fd\t ngh\u0129a\t kh\u00e1ch\t quan\t \u0111\u1ed1i\t v\u1edbi\t th\u1ebf gi\u1edbi\t \u0111\u01b0\u1ee3c\t m\u1edf\t r\u1ed9ng\t v\u1ec1\t kh\u00f4ng\t gian.\t \u0110i\u1ec1u\t \u0111\u00f3\t l\u00e0\t v\u00ec\t ng\u01b0\u1eddi\t ta\t ph\u1ea3i quan\t ni\u1ec7m\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian\t l\u00e0\t m\u1ed9t\t continum\t kh\u00f4ng\t th\u1ec3 ph\u00e2n\tgi\u1ea3i\tra\t\u0111\u01b0\u1ee3c\tm\u1ed9t\tc\u00e1ch\tkh\u00e1ch\tquan,\tn\u1ebfu\tng\u01b0\u1eddi\tta\tmu\u1ed1n\tdi\u1ec5n t\u1ea3\tn\u1ed9i\tdung\tc\u1ee7a\tc\u00e1c\tquan\th\u1ec7\tkh\u00e1ch\tquan\tm\u00e0\tkh\u00f4ng\tc\u00f3\ts\u1ef1\tt\u00f9y\tti\u1ec7n \u01b0\u1edbc\tl\u1ec7\tkh\u00f4ng\tc\u1ea7n\tthi\u1ebft. B\u1eb1ng\tc\u00e1ch\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p\tb\u1ed9c\tl\u1ed9\tt\u00ednh\tt\u01b0\u01a1ng\t\u0111\u01b0\u01a1ng\tv\u1eadt\tl\u00fd c\u1ee7a\t t\u1ea5t\t c\u1ea3\t c\u00e1c\t h\u1ec7\t qu\u00e1n\t t\u00ednh,\t n\u00f3\t ch\u1ee9ng\t minh\t kh\u00f4ng\t th\u1ec3\t b\u1ea3o\t v\u1ec7 \u0111\u01b0\u1ee3c\t gi\u1ea3\t thuy\u1ebft\t v\u1ec1\t ether\t y\u00ean\t t\u0129nh.\t Do\t \u0111\u00f3\t ng\u01b0\u1eddi\t ta\t ph\u1ea3i\t t\u1eeb\t b\u1ecf\t \u00fd t\u01b0\u1edfng\t r\u1eb1ng\t tr\u01b0\u1eddng\t \u0111i\u1ec7n\t t\u1eeb\t ph\u1ea3i\t \u0111\u01b0\u1ee3c\t quan\t ni\u1ec7m\t nh\u01b0\t tr\u1ea1ng\t th\u00e1i c\u1ee7a\t m\u1ed9t\t m\u00f4i\t tr\u01b0\u1eddng\t n\u1ec1n\t v\u1eadt\t ch\u1ea5t.\t Tr\u01b0\u1eddng,\t do\t \u0111\u00f3,\t tr\u1edf\t th\u00e0nh\t m\u1ed9t nh\u00e2n\t t\u1ed1\t kh\u00f4ng\t r\u00fat\t g\u1ecdn\t \u0111\u01b0\u1ee3c\t c\u1ee7a\t s\u1ef1\t m\u00f4\t t\u1ea3\t v\u1eadt\t l\u00fd,\t kh\u00f4ng\t r\u00fat\t g\u1ecdn \u0111\u01b0\u1ee3c\t theo\t c\u00f9ng\t ngh\u0129a\t nh\u01b0\t kh\u00e1i\t ni\u1ec7m\t c\u1ee7a\t v\u1eadt\t ch\u1ea5t\t trong\t thuy\u1ebft Newton. Cho\t\u0111\u1ebfn\tgi\u1edd,\tch\u00fang\tta\t\u0111\u00e3\th\u01b0\u1edbng\ts\u1ef1\tch\u00fa\t\u00fd\t\u0111\u1ebfn\tvi\u1ec7c\tt\u00ecm\thi\u1ec3u\tc\u00e1c kh\u00e1i\t ni\u1ec7m\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t c\u1ea3i\tbi\u00ean\t th\u1ebf\t n\u00e0o\t b\u1edfi thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p.\t B\u00e2y\t gi\u1edd\t ch\u00fang\t ta\t h\u00e3y\t ch\u00fa\t \u00fd\t \u0111\u1ebfn\t c\u00e1c\t nh\u00e2n t\u1ed1\t m\u00e0\t thuy\u1ebft\t n\u00e0y\t \u0111\u00e3\t ti\u1ebfp\t thu\t t\u1eeb\t c\u01a1\t h\u1ecdc\t c\u1ed5\t \u0111i\u1ec3n.\t \u1ede\t \u0111\u00e2y\t c\u0169ng\t th\u1ebf, c\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tt\u1ef1\tnhi\u00ean\tch\u1ec9\t\u0111\u00f2i\th\u1ecfi\tt\u00ednh\thi\u1ec7u\tl\u1ef1c\tkhi\tm\u1ed9t\th\u1ec7\tqu\u00e1n t\u00ednh\t\u0111\u01b0\u1ee3c\tch\u1ecdn\tl\u00e0m\tc\u01a1\ts\u1edf\tcho\ts\u1ef1\tm\u00f4\tt\u1ea3\tkh\u00f4ng-th\u1eddi-gian.\tNguy\u00ean l\u00fd\t qu\u00e1n\t t\u00ednh\t v\u00e0\t nguy\u00ean\t l\u00fd\t h\u1eb1ng\t s\u1ed1\t v\u1eadn\t t\u1ed1c\t truy\u1ec1n\t c\u1ee7a\t \u00e1nh\t s\u00e1ng","ch\u1ec9\t \u0111\u00fang\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed9t\t h\u1ec7\t qu\u00e1n\t t\u00ednh.\t C\u0169ng\t th\u1ebf,\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t v\u1ec1 tr\u01b0\u1eddng\tch\u1ec9\tc\u00f3\t\u00fd\tngh\u0129a\tv\u00e0\thi\u1ec7u\tl\u1ef1c\t\u0111\u1ed1i\tv\u1edbi\tc\u00e1c\th\u1ec7\tqu\u00e1n\tt\u00ednh.\tDo\t\u0111\u00f3, c\u0169ng\tnh\u01b0\ttrong\tc\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n,\tkh\u00f4ng\tgian\t\u1edf\t\u0111\u00e2y\tc\u0169ng\tl\u00e0\tm\u1ed9t\tb\u1ed9 ph\u1eadn\t \u0111\u1ed9c\t l\u1eadp\t trong\t s\u1ef1\t m\u00f4\t t\u1ea3\t th\u1ef1c\t t\u1ea1i\t v\u1eadt\t l\u00fd.\t Kh\u00f4ng\t gian\t (qu\u00e1n t\u00ednh)\t-\thay\tr\u00f5\th\u01a1n\t-\thay\t\u0111\u00fang\th\u01a1n,\tkh\u00f4ng\tgian\tn\u00e0y\tc\u00f9ng\tv\u1edbi\tth\u1eddi gian\t li\u00ean\t k\u1ebft\t c\u1ee7a\t n\u00f3\t -\t v\u1eabn\t c\u00f2n\t t\u1ed3n\t t\u1ea1i\t khi\t ng\u01b0\u1eddi\t ta\t t\u01b0\u1edfng\t t\u01b0\u1ee3ng v\u1eadt\tch\u1ea5t\tv\u00e0\ttr\u01b0\u1eddng\t\u0111\u00e3\t\u0111\u01b0\u1ee3c\tl\u1ea5y\t\u0111i.\tC\u1ea5u\ttr\u00fac\tb\u1ed1n\tchi\u1ec1u\tn\u00e0y\t(kh\u00f4ng gian\t Minkowski)\t \u0111\u01b0\u1ee3c\t quan\t ni\u1ec7m\t l\u00e0\t c\u00e1i\t gi\u00e1\t t\u1ea3i\t c\u1ee7a\t v\u1eadt\t ch\u1ea5t\t v\u00e0 tr\u01b0\u1eddng.\t C\u00e1c\t kh\u00f4ng\t gian\t qu\u00e1n\t t\u00ednh,\t v\u1edbi\t c\u00e1c\t th\u1eddi\t gian\t li\u00ean\t k\u1ebft\t c\u1ee7a ch\u00fang,\tch\u1ec9\tl\u00e0\tnh\u1eefng\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tb\u1ed1n\tchi\u1ec1u\t\u01b0u\t\u0111\u00e3i,\tch\u00fang\t\u0111\u01b0\u1ee3c\tn\u1ed1i k\u1ebft\t v\u1edbi\t nhau\t b\u1eb1ng\t c\u00e1c\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i\t tuy\u1ebfn\t t\u00ednh\t Lorentz.\t B\u1edfi\t v\u00ec trong\t c\u1ea5u\t tr\u00fac\t b\u1ed1n\t chi\u1ec1u\t n\u00e0y\t kh\u00f4ng\t c\u00f3\t n\u1eefa\t nh\u1eefng\t l\u00e1t\t c\u1eaft\t t\u01b0\u1ee3ng tr\u01b0ng\t kh\u00e1ch\t quan\t cho\t \\\"b\u00e2y\t gi\u1edd\\\",\t n\u00ean\t c\u00e1c\t kh\u00e1i\t ni\u1ec7m\t v\u1ec1\t s\u1ef1\t ki\u1ec7n (x\u1ea3y\tra)\thay\tdi\u1ec5n\tbi\u1ebfn\t(ti\u1ebfn\th\u00f3a)\ttuy\tkh\u00f4ng\tho\u00e0n\tto\u00e0n\tb\u1ecb\tx\u00f3a\tb\u1ecf, nh\u01b0ng\t l\u1ea1i\t ph\u1ee9c\t t\u1ea1p.\t Cho\t n\u00ean\t s\u1ebd\t l\u00e0\t t\u1ef1\t nhi\u00ean\t h\u01a1n,\t n\u1ebfu\t ch\u00fang\t ta ngh\u0129\tc\u00e1i\tth\u1ef1c\tt\u1ea1i\tv\u1eadt\tl\u00fd\tnh\u01b0\tm\u1ed9t\ts\u1ef1\tt\u1ed3n\tt\u1ea1i\tb\u1ed1n\tchi\u1ec1u,\tthay\tv\u00ec\tcho \u0111\u1ebfn\tnay\tnh\u01b0\tl\u00e0\tm\u1ed9t\ts\u1ef1\tti\u1ebfn\th\u00f3a\ttrong\tkh\u00f4ng\tgian\tba\tchi\u1ec1u. Kh\u00f4ng\t gian\t b\u1ed1n\t chi\u1ec1u\t r\u1eafn\t n\u00e0y\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p,\t \u1edf m\u1ee9c\t \u0111\u1ed9\t n\u00e0o\t \u0111\u00f3,\t l\u00e0\t m\u1ed9t\t c\u00e1i\t t\u01b0\u01a1ng\t t\u1ef1\t b\u1ed1n\t chi\u1ec1u\t c\u1ee7a\t m\u00f4i\t tr\u01b0\u1eddng ether\t ba\t chi\u1ec1u\t r\u1eafn\t c\u1ee7a\t H.A.\t Lorentz.\t \u0110\u1ed1i\t v\u1edbi\t thuy\u1ebft\t n\u00e0y,\t s\u1ef1\t ph\u00e1t bi\u1ec3u\t sau\t \u0111\u00e2y\t c\u0169ng\t c\u00f3\t hi\u1ec7u\t l\u1ef1c:\t S\u1ef1\t m\u00f4\t t\u1ea3\t c\u00e1c\t tr\u1ea1ng\t th\u00e1i\t v\u1eadt\t l\u00fd\t gi\u1ea3 \u0111\u1ecbnh\tr\u1eb1ng\tkh\u00f4ng\tgian\t\u0111\u01b0\u1ee3c\tcho\ttr\u01b0\u1edbc\tt\u1eeb\t\u0111\u1ea7u,\tc\u0169ng\tnh\u01b0\tgi\u1ea3\t\u0111\u1ecbnh n\u00f3\t t\u1ed3n\t t\u1ea1i\t m\u1ed9t\t c\u00e1ch\t \u0111\u1ed9c\t l\u1eadp.\t Cho\t n\u00ean\t l\u00fd\t thuy\u1ebft\t n\u00e0y\t c\u0169ng\t kh\u00f4ng lo\u1ea1i\t b\u1ecf\t \u0111\u01b0\u1ee3c\t s\u1ef1\t kh\u00f3\t ch\u1ecbu\t c\u1ee7a\t Descartes\t li\u00ean\t quan\t \u0111\u1ebfn\t s\u1ef1\t t\u1ed3n\t t\u1ea1i \u0111\u1ed9c\tl\u1eadp,\tv\u00e0\tc\u1ea3\tti\u00ean\tnghi\u1ec7m,\tc\u1ee7a\t\\\"kh\u00f4ng\tgian\tr\u1ed7ng\\\".\t\u1ede\tm\u1ee9c\t\u0111\u1ed9\tn\u00e0o s\u1ef1\tquan\tng\u1ea1i\tn\u00e0y\t\u0111\u01b0\u1ee3c\tgi\u1ea3i\tt\u1ecfa\tb\u1eb1ng\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng,\t\u0111\u00f3\tl\u00e0 m\u1ee5c\t\u0111\u00edch\tch\u00ednh\tc\u1ee7a\tnh\u1eefng\tsuy\tngh\u0129\tc\u01a1\tb\u1ea3n\t\u0111\u01b0\u1ee3c\ttr\u00ecnh\tb\u00e0y\t\u1edf\t\u0111\u00e2y. \u00dd\tT\u01af\u1edeNG\tKH\u00d4NG\tGIAN\tTRONG\tTHUY\u1ebeT\tT\u01af\u01a0NG\t\u0110\u1ed0I\tR\u1ed8NG Thuy\u1ebft\tn\u00e0y\ttr\u01b0\u1edbc\tti\u00ean\tb\u1eaft\tngu\u1ed3n\tt\u1eeb\tn\u1ed7\tl\u1ef1c\tmu\u1ed1n\thi\u1ec3u\t\u0111\u01b0\u1ee3c\ts\u1ef1 t\u01b0\u01a1ng\t \u0111\u01b0\u01a1ng\t c\u1ee7a\t kh\u1ed1i\t l\u01b0\u1ee3ng\t qu\u00e1n\t t\u00ednh\t v\u00e0\t kh\u1ed1i\t l\u01b0\u1ee3ng\t h\u1ea5p\t d\u1eabn. 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X\u00e9t\tm\u1ed9t\tc\u00e1ch\tb\u1ed1n\tchi\u1ec1u,\tt\u01b0\u01a1ng\t\u1ee9ng\tv\u1edbi\ts\u1ef1\tbi\u1ebfn\t\u0111\u1ed5i\tt\u1eeb\tS1\tsang S2\ts\u1ebd\tl\u00e0\tm\u1ed9t\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tphi\ttuy\u1ebfn\tc\u1ee7a\tb\u1ed1n\tt\u1ecda\t\u0111\u1ed9.\tM\u1ed9t\tc\u00e2u\th\u1ecfi \u0111\u1eb7t\t ra:\t Nh\u1eefng\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i\t phi\t tuy\u1ebfn\t n\u00e0o\t n\u00ean\t \u0111\u01b0\u1ee3c\t cho\t ph\u00e9p, hay:\tPh\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tLorentz\t\u0111\u01b0\u1ee3c\tn\u1edbi\tr\u1ed9ng\tra\tnh\u01b0\tth\u1ebf\tn\u00e0o?\t\u0110\u1ec3\ttr\u1ea3 l\u1eddi\tc\u00e2u\th\u1ecfi\tn\u00e0y,\tsuy\tngh\u0129\tsau\t\u0111\u00e2y\tl\u00e0\tquy\u1ebft\t\u0111\u1ecbnh. 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D\u00f2ng\t \u00fd\t t\u01b0\u1edfng\t n\u00e0y\t c\u01a1\t b\u1ea3n\t \u0111\u01b0\u1ee3c\t x\u00e2y\t d\u1ef1ng\t tr\u00ean\t kh\u00e1i\t ni\u1ec7m tr\u01b0\u1eddng\tnh\u01b0\tm\u1ed9t\tkh\u00e1i\tni\u1ec7m\t\u0111\u1ed9c\tl\u1eadp.\tB\u1edfi\tv\u00ec\tc\u00e1c\tquan\th\u1ec7\tt\u1ed3n\tt\u1ea1i\t\u0111\u1ed1i v\u1edbi\tS2\t\u0111\u01b0\u1ee3c\tl\u00fd\tgi\u1ea3i\tnh\u01b0\tm\u1ed9t\ttr\u01b0\u1eddng\th\u1ea5p\td\u1eabn,\tm\u00e0\tkh\u00f4ng\tc\u1ea7n\t\u0111\u1eb7t\tra v\u1ea5n\t\u0111\u1ec1\tt\u1ed3n\tt\u1ea1i\tc\u1ee7a\tc\u00e1c\tkh\u1ed1i\tl\u01b0\u1ee3ng,\tnh\u1eefng\tth\u1ee9\tv\u1ed1n\tsinh\tra\ttr\u01b0\u1eddng n\u00e0y.\t D\u00f2ng\t \u00fd\t t\u01b0\u1edfng\t n\u00e0y\t c\u0169ng\t l\u00e0m\t cho\t ng\u01b0\u1eddi\t ta\t hi\u1ec3u\t t\u1ea1i\t sao\t c\u00e1c \u0111\u1ecbnh\tlu\u1eadt\tc\u1ee7a\ttr\u01b0\u1eddng\th\u1ea5p\td\u1eabn\tthu\u1ea7n\tt\u00fay\tl\u1ea1i\t\u0111\u01b0\u1ee3c\tli\u00ean\th\u1ec7\ttr\u1ef1c\tti\u1ebfp v\u1edbi\t \u00fd\t t\u01b0\u1edfng\t c\u1ee7a\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng\t tr\u1ef1c\t ti\u1ebfp\t h\u01a1n\t l\u00e0\t c\u00e1c \u0111\u1ecbnh\tlu\u1eadt\tc\u1ee7a\tc\u00e1c\ttr\u01b0\u1eddng\tc\u00f3\td\u1ea1ng\tph\u1ed5\tqu\u00e1t\t(khi\tch\u1eb3ng\th\u1ea1n\tc\u00f3\tm\u1ed9t tr\u01b0\u1eddng\t\u0111i\u1ec7n\tt\u1eeb\tt\u1ed3n\tt\u1ea1i).\tTh\u1eadt\tv\u1eady,\tch\u00fang\tta\tc\u00f3\tc\u01a1\ts\u1edf\tch\u00ednh\t\u0111\u00e1ng\t\u0111\u1ec3 gi\u1ea3\t thi\u1ebft\t r\u1eb1ng\t kh\u00f4ng\t gian\t Minkowski\t \\\"v\u00f4\t tr\u01b0\u1eddng\\\"\t (kh\u00f4ng\t c\u00f3 tr\u01b0\u1eddng)\t bi\u1ec3u\t th\u1ecb\t m\u1ed9t\t tr\u01b0\u1eddng\t h\u1ee3p\t \u0111\u1eb7c\t bi\u1ec7t\t kh\u1ea3\t d\u0129\t trong\t \u0111\u1ecbnh\t lu\u1eadt t\u1ef1\t nhi\u00ean,\t v\u00e0\t l\u00e0\t tr\u01b0\u1eddng\t h\u1ee3p\t \u0111\u1eb7c\t bi\u1ec7t\t \u0111\u01a1n\t gi\u1ea3n\t nh\u1ea5t\t c\u00f3\t th\u1ec3\t quan ni\u1ec7m\t\u0111\u01b0\u1ee3c.\tX\u00e9t\tv\u1ec1\tt\u00ednh\tch\u1ea5t\tmetric\tc\u1ee7a\tn\u00f3,\tm\u1ed9t\tkh\u00f4ng\tgian\tnh\u01b0 th\u1ebf\t\u0111\u01b0\u1ee3c\t\u0111\u1eb7c\ttr\u01b0ng\tb\u1edfi\tt\u00ednh\tch\u1ea5t\tr\u1eb1ng\tbi\u1ec3u\tth\u1ee9c\tdx1\t2\t+\t dx2\t 2\t + dx3\t 2\t ,\t \u0111\u01b0\u1ee3c\t \u0111o\t b\u1eb1ng\t m\u1ed9t\t \u0111\u01a1n\t v\u1ecb\t \u0111o\t l\u01b0\u1eddng,\t l\u00e0\t b\u00ecnh\t ph\u01b0\u01a1ng\t c\u1ee7a kho\u1ea3ng\t c\u00e1ch\t kh\u00f4ng\t gian\t c\u1ee7a\t hai\t \u0111i\u1ec3m\t l\u00e2n\t c\u1eadn\t vi\t ph\u00e2n\t c\u1ee7a\t m\u1ed9t l\u00e1t\t c\u1eaft\t lo\u1ea1i-kh\u00f4ng\t gian\t ba\t chi\u1ec1u\t (\u0111\u1ecbnh\t l\u00fd\t Pythagore),\t trong\t khi dx4\tl\u00e0\tkho\u1ea3ng\tc\u00e1ch\tth\u1eddi\tgian,\t\u0111\u01b0\u1ee3c\t\u0111o\tb\u1eb1ng\tm\u1ed9t\t\u0111\u01a1n\tv\u1ecb\tth\u1eddi\tgian th\u00edch\th\u1ee3p,\tc\u1ee7a\thai\ts\u1ef1\tki\u1ec7n\tv\u1edbi\tnh\u1eefng\tt\u1ecda\t\u0111\u1ed9\tchung\t(x1,\t x2,\t x3). T\u1ea5t\tc\u1ea3\tnh\u1eefng\t\u0111i\u1ec1u\tn\u00e0y\tchung\tquy\td\u1eabn\tt\u1edbi\tk\u1ebft\tqu\u1ea3,\t\u0111i\u1ec1u\tc\u00f3\tth\u1ec3\td\u1ec5 d\u00e0ng\t \u0111\u01b0\u1ee3c\t ch\u1ee9ng\t minh\t v\u1edbi\t s\u1ef1\t gi\u00fap\t \u0111\u1ee1\t c\u1ee7a\t c\u00e1c\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i Lorentz,\tr\u1eb1ng\t\u0111\u1ea1i\tl\u01b0\u1ee3ng ds\t2\t=\tdx1\t2\t+\tdx\t2\t+\tdx3\t2\t\u2013\tdx4\t2\t(1) mang\t m\u1ed9t\t \u00fd\t ngh\u0129a\t metric\t kh\u00e1ch\t quan,\t v\u1ec1\t m\u1eb7t\t to\u00e1n\t h\u1ecdc,\t \u0111i\u1ec1u n\u00e0y\tt\u01b0\u01a1ng\t\u1ee9ng\tv\u1edbi\tvi\u1ec7c\tds\t2\tl\u00e0\tm\u1ed9t\t\u0111\u1ea1i\tl\u01b0\u1ee3ng\tb\u1ea5t\tbi\u1ebfn\t\u0111\u1ed1i\tv\u1edbi\tc\u00e1c ph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tLorentz. N\u1ebfu\tgi\u1edd,\ttheo\tngh\u0129a\tc\u1ee7a\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng,\tch\u00fang\tta\t\u00e1p l\u00ean\tkh\u00f4ng\tgian\tn\u00e0y\tm\u1ed9t\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tli\u00ean\tt\u1ee5c\tb\u1ea5t\tk\u1ef3\tc\u1ee7a\tc\u00e1c\tt\u1ecda \u0111\u1ed9,\t th\u00ec\t \u0111\u1ed9\t l\u1edbn\t h\u1ee3p\t l\u00fd\t kh\u00e1ch\t quan\t ds\t s\u1ebd\t \u0111\u01b0\u1ee3c\t di\u1ec5n\t t\u1ea3\t trong\t h\u1ec7\t t\u1ecda \u0111\u1ed9\tm\u1edbi\tb\u1eb1ng\th\u1ec7\tth\u1ee9c ds\t2\t=\tg\tik\tdx\ti\tdx\tk\t(1a)","trong\t \u0111\u00f3\t v\u1ebf\t ph\u1ea3i\t l\u00e0\t m\u1ed9t\t t\u1ed5ng\t s\u1ed1[88]\t khi\t c\u00e1c\t ch\u1ec9\t s\u1ed1\t i\t v\u00e0\t k\t bi\u1ebfn thi\u00ean\t tr\u00ean\t c\u00e1c\t t\u1ed5\t h\u1ee3p\t 11,\t 12,...\t cho\t \u0111\u1ebfn\t 44.\t C\u00e1c\t s\u1ed1\t h\u1ea1ng\t g\tik\tb\u00e2y gi\u1edd\t kh\u00f4ng\t ph\u1ea3i\t l\u00e0\t h\u1eb1ng\t s\u1ed1\t m\u00e0\t l\u00e0\t h\u00e0m\t s\u1ed1\t c\u1ee7a\t c\u00e1c\t t\u1ecda\t \u0111\u1ed9\t v\u00e0\t \u0111\u01b0\u1ee3c x\u00e1c\t\u0111\u1ecbnh\tb\u1edfi\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\t\u0111\u01b0\u1ee3c\tch\u1ecdn\tb\u1ea5t\tk\u1ef3\t(v\u1eeba\tn\u00f3i).\tTuy\tnhi\u00ean c\u00e1c\tg\tik\tkh\u00f4ng\tph\u1ea3i\tl\u00e0\tnh\u1eefng\th\u00e0m\ts\u1ed1\tt\u00f9y\tti\u1ec7n\tc\u1ee7a\tc\u00e1c\tt\u1ecda\t\u0111\u1ed9\tm\u1edbi, m\u00e0\t ph\u1ea3i\t l\u00e0\t c\u00e1c\t h\u00e0m\t s\u1ed1\t sao\t cho\t h\u1ec7\t th\u1ee9c\t (la)\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t bi\u1ebfn\t \u0111\u1ed5i ng\u01b0\u1ee3c\tl\u1ea1i\tth\u00e0nh\t(1)\tb\u1eb1ng\tm\u1ed9t\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed1i\tli\u00ean\tt\u1ee5c\tc\u1ee7a\tb\u1ed1n\tt\u1ecda \u0111\u1ed9.\t\u0110\u1ec3\t\u0111i\u1ec1u\t\u0111\u00f3\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\tth\u1ef1c\thi\u1ec7n,\tc\u00e1c\th\u00e0m\ts\u1ed1\tg\t ik\t ph\u1ea3i\t th\u1ecfa m\u00e3n\t c\u00e1c\t \\\"ph\u01b0\u01a1ng\t tr\u00ecnh\t c\u1ee7a\t \u0111i\u1ec1u\t ki\u1ec7n\\\"\t nh\u1ea5t\t \u0111\u1ecbnh\t c\u00f3\t t\u00ednh\t ch\u1ea5t hi\u1ec7p\tbi\u1ebfn\tm\u00e0\tB.\tRiemann\t\u0111\u00e3\tr\u00fat\tra\th\u01a1n\tm\u1ed9t\tn\u1eeda\tth\u1ebf\tk\u1ef7\ttr\u01b0\u1edbc\tkhi thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng\t \u0111\u01b0\u1ee3c\t thi\u1ebft\t l\u1eadp\t (\\\"\u0110i\u1ec1u\t ki\u1ec7n\t Riemann\t \\\"). Theo\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u01b0\u01a1ng,\t(la)\tm\u00f4\tt\u1ea3\td\u01b0\u1edbi\td\u1ea1ng\thi\u1ec7p\tbi\u1ebfn\tt\u1ed5ng qu\u00e1t\tm\u1ed9t\ttr\u01b0\u1eddng\th\u1ea5p\td\u1eabn\tlo\u1ea1i\t\u0111\u1eb7c\tbi\u1ec7t,\tn\u1ebfu\tc\u00e1c\tg\tik\tth\u1ecfa\tm\u00e3n\t\u0111i\u1ec1u ki\u1ec7n\tRiemann. \u0110\u1ecbnh\t lu\u1eadt\t cho\t tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn\t thu\u1ea7n\t t\u00fay\t c\u1ee7a\t d\u1ea1ng\t t\u1ed5ng\t qu\u00e1t do\t\u0111\u00f3\tph\u1ea3i\t\u0111\u01b0\u1ee3c\tth\u1ecfa\tm\u00e3n\tkhi\t\u0111i\u1ec1u\tki\u1ec7n\tRiemann\t\u0111\u01b0\u1ee3c\tth\u1ecfa\tm\u00e3n; nh\u01b0ng\tn\u00f3\t(\u0111\u1ecbnh\tlu\u1eadt)\tph\u1ea3i\ty\u1ebfu\th\u01a1n,\tngh\u0129a\tl\u00e0\t\u00edt\tgi\u1edbi\th\u1ea1n\th\u01a1n\t\u0111i\u1ec1u ki\u1ec7n\t Riemann.\t B\u1eb1ng\t c\u00e1ch\t \u0111\u00f3,\t \u0111\u1ecbnh\t lu\u1eadt\t tr\u01b0\u1eddng\t c\u1ee7a\t l\u1ef1c\t h\u1ea5p\t d\u1eabn thu\u1ea7n\t t\u00fay\t th\u1ef1c\t t\u1ebf\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t ho\u00e0n\t to\u00e0n\t x\u00e1c\t \u0111\u1ecbnh,\t m\u1ed9t\t k\u1ebft\t qu\u1ea3\t s\u1ebd kh\u00f4ng\t\u0111\u01b0\u1ee3c\tdi\u1ec5n\tgi\u1ea3i\tchi\tti\u1ebft\t\u1edf\t\u0111\u00e2y. B\u00e2y\t gi\u1edd\t ch\u00fang\t ta\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t chu\u1ea9n\t b\u1ecb\t \u0111\u1ec3\t th\u1ea5y\t \u0111\u01b0\u1ee3c\t s\u1ef1\t chuy\u1ec3n ti\u1ebfp\tsang\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng\ts\u1eeda\t\u0111\u1ed5i\tkh\u00e1i\tni\u1ec7m\tkh\u00f4ng\tgian\t\u1edf m\u1ee9c\t\u0111\u1ed9\tn\u00e0o.\tTheo\tc\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n\tv\u00e0\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p,\tkh\u00f4ng gian\t(kh\u00f4ng-th\u1eddi-gian)\tc\u00f3\tm\u1ed9t\ts\u1ef1\tt\u1ed3n\tt\u1ea1i\t\u0111\u1ed9c\tl\u1eadp\t\u0111\u1ed1i\tv\u1edbi\tv\u1eadt\tch\u1ea5t hay\t v\u1edbi\t tr\u01b0\u1eddng.\t N\u00f3i\t chung\t \u0111\u1ec3\t c\u00f3\t th\u1ec3\t m\u00f4\t t\u1ea3\t \\\"c\u00e1i\t l\u1ea5p\t \u0111\u1ea7y\t kh\u00f4ng gian\\\"\t v\u00e0\t l\u1ec7\t thu\u1ed9c\t v\u00e0o\t t\u1ecda\t \u0111\u1ed9,\t th\u00ec\t kh\u00f4ng-th\u1eddi-gian\t hay\t h\u1ec7\t qu\u00e1n t\u00ednh\tph\u1ea3i\t\u0111\u01b0\u1ee3c\tquan\tni\u1ec7m\tl\u00e0\tt\u1ed3n\tt\u1ea1i\tngay\tt\u1eeb\t\u0111\u1ea7u\tc\u00f9ng\tv\u1edbi\tnh\u1eefng t\u00ednh\t ch\u1ea5t\t metric\t c\u1ee7a\t n\u00f3,\t b\u1edfi\t v\u00ec\t n\u1ebfu\t kh\u00f4ng,\t s\u1ef1\t m\u00f4\t t\u1ea3\t c\u1ee7a\t c\u00e1i\t \\\"l\u1ea5p \u0111\u1ea7y\t kh\u00f4ng\t gian\\\"\t s\u1ebd\t kh\u00f4ng\t c\u00f3\t \u00fd\t ngh\u0129a.[89]\t Nh\u01b0ng\t theo\t thuy\u1ebft t\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng,\tkh\u00f4ng\tgian\tng\u01b0\u1ee3c\tl\u1ea1i\tkh\u00f4ng\tc\u00f3\ts\u1ef1\tt\u1ed3n\tt\u1ea1i\t\u0111\u1eb7c\tbi\u1ec7t n\u00e0o\t \u0111\u1ed1i\t v\u1edbi\t \\\"c\u00e1i\t l\u1ea5p\t \u0111\u1ea7y\t kh\u00f4ng\t gian\\\",\t l\u1ec7\t thu\u1ed9c\t v\u00e0o\t c\u00e1c\t t\u1ecda\t \u0111\u1ed9. Ch\u1eb3ng\t h\u1ea1n\t gi\u1ea3\t thi\u1ebft\t ng\u01b0\u1eddi\t ta\t m\u00f4\t t\u1ea3\t m\u1ed9t\t tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn\t thu\u1ea7n t\u00fay\tb\u1eb1ng\tc\u00e1c\tg\tik\t(nh\u01b0\th\u00e0m\ts\u1ed1\tc\u1ee7a\tc\u00e1c\tt\u1ecda\t\u0111\u1ed9)\tnh\u01b0\tnghi\u1ec7m\ts\u1ed1\tc\u1ee7a c\u00e1c\t ph\u01b0\u01a1ng\t tr\u00ecnh\t h\u1ea5p\t d\u1eabn.\t Khi\t ng\u01b0\u1eddi\t ta\t ngh\u0129\t l\u1ea5y\t \u0111i\t tr\u01b0\u1eddng\t h\u1ea5p d\u1eabn,\t ngh\u0129a\t l\u00e0\t l\u1ea5y\t \u0111i\t c\u00e1c\t h\u00e0m\t s\u1ed1\t g\t ik\t ,\t th\u00ec\t kh\u00f4ng\t c\u00f2n\t m\u1ed9t\t kh\u00f4ng gian\tc\u1ee7a\td\u1ea1ng\t(1),\tm\u00e0\tn\u00f3i\tchung,\tch\u1eb3ng\tc\u00f2n\tl\u1ea1i\tg\u00ec\tc\u1ea3,\tk\u1ec3\tc\u1ea3\t\\\"kh\u00f4ng gian\tt\u00f4p\u00f4\\\".\tB\u1edfi\tv\u00ec\tc\u00e1c\th\u00e0m\ts\u1ed1\tg\tik\tm\u00f4\tt\u1ea3\tkh\u00f4ng\tnh\u1eefng\ttr\u01b0\u1eddng,\tm\u00e0 \u0111\u1ed3ng\t th\u1eddi\t c\u00f2n\t m\u00f4\t t\u1ea3\t c\u1ea5u\t tr\u00fac\t t\u00f4p\u00f4\t v\u00e0\t metric\t -\t c\u00e1c\t t\u00ednh\t ch\u1ea5t\t c\u1ee7a","\u0111a\tt\u1ea1p.\tM\u1ed9t\tkh\u00f4ng\tgian\tki\u1ec3u\t(1),\ttheo\tngh\u0129a\tc\u1ee7a\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i r\u1ed9ng,\t kh\u00f4ng\t ph\u1ea3i\t l\u00e0\t m\u1ed9t\t kh\u00f4ng\t gian\t kh\u00f4ng\t tr\u01b0\u1eddng,\t m\u00e0\t l\u00e0\t m\u1ed9t tr\u01b0\u1eddng\th\u1ee3p\t\u0111\u1eb7c\tbi\u1ec7t\tc\u1ee7a\ttr\u01b0\u1eddng\t(g\tik),\t\u1edf\t\u0111\u00f3\tc\u00e1c\tg\tik\t(\u0111\u1ed1i\tv\u1edbi\th\u1ec7\tt\u1ecda \u0111\u1ed9\t \u0111\u01b0\u1ee3c\t s\u1eed\t d\u1ee5ng,\t c\u00e1i\t th\u1ef1c\t ra\t kh\u00f4ng\t c\u00f3\t \u00fd\t ngh\u0129a\t kh\u00e1ch\t quan)\t c\u00f3 nh\u1eefng\t tr\u1ecb\t s\u1ed1\t kh\u00f4ng\t t\u00f9y\t thu\u1ed9c\t v\u00e0o\t c\u00e1c\t t\u1ecda\t \u0111\u1ed9;\t m\u1ed9t\t kh\u00f4ng\t gian r\u1ed7ng,\tngh\u0129a\tl\u00e0\tm\u1ed9t\tkh\u00f4ng\tgian\tkh\u00f4ng\tc\u00f3\ttr\u01b0\u1eddng,\tc\u00e1i\t\u0111\u00f3\tkh\u00f4ng\tth\u1ec3 c\u00f3.\tKh\u00f4ng-th\u1eddi-gian\tt\u1ef1\tn\u00f3\tkh\u00f4ng\t\u0111\u00f2i\th\u1ecfi\ts\u1ef1\tt\u1ed3n\tt\u1ea1i\tri\u00eang\tc\u1ee7a\tn\u00f3, nh\u01b0ng\tch\u1ec9\tl\u00e0\tm\u1ed9t\t\u0111\u1eb7c\tt\u00ednh\tv\u1ec1\tc\u1ea5u\ttr\u00fac\tc\u1ee7a\ttr\u01b0\u1eddng\tm\u00e0\tth\u00f4i.[90] Do\t \u0111\u00f3\t Descartes\t kh\u00f4ng\t ph\u1ea3i\t kh\u00f4ng\t c\u00f3\t l\u00fd\t l\u1eafm\t khi\t \u00f4ng\t tin\t c\u1ea7n ph\u1ea3i\t lo\u1ea1i\t b\u1ecf\t s\u1ef1\t t\u1ed3n\t t\u1ea1i\t c\u1ee7a\t kh\u00f4ng\t gian\t r\u1ed7ng.\t \u00dd\t t\u01b0\u1edfng\t xem\t ra\t tuy v\u00f4\tl\u00fd,\tnh\u01b0ng\tbao\tl\u00e2u\tng\u01b0\u1eddi\tta\tch\u1ec9\tnh\u00ecn\tc\u00e1i\tth\u1ef1c\tt\u1ea1i\tv\u1eadt\tl\u00fd\tqua\tc\u00e1c v\u1eadt\tth\u1ec3\tc\u00f3\ttr\u1ecdng\tl\u01b0\u1ee3ng.\tCh\u1ec9\tc\u00f3\t\u00fd\tt\u01b0\u1edfng\ttr\u01b0\u1eddng\tv\u1edbi\tt\u01b0\tc\u00e1ch\tl\u00e0\tng\u01b0\u1eddi th\u1ee7\tvai\tc\u1ee7a\tth\u1ef1c\tt\u1ea1i,\tv\u00e0\ttrong\ts\u1ef1\tk\u1ebft\th\u1ee3p\tv\u1edbi\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i r\u1ed9ng,\tm\u1edbi\tch\u1ec9\tra\t\u0111\u01b0\u1ee3c\tc\u00e1i\tl\u00f5i\tth\u1ef1c\tc\u1ee7a\t\u00fd\tt\u01b0\u1edfng\tDescartes:\tkh\u00f4ng\tc\u00f3 kh\u00f4ng\tgian\t\\\"v\u00f4\ttr\u01b0\u1eddng\\\". THUY\u1ebeT\tH\u1ea4P\tD\u1eaaN\tM\u1ede\tR\u1ed8NG Thuy\u1ebft\t tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn\t thu\u1ea7n\t t\u00fay\t tr\u00ean\t mi\u1ebfng\t \u0111\u1ea5t\t c\u1ee7a\t thuy\u1ebft t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng\t v\u00ec\t th\u1ebf\t d\u1ec5\t ti\u1ebfp\t c\u1eadn,\t v\u00ec\t ch\u00fang\t ta\t \u0111\u01b0\u1ee3c\t ph\u00e9p\t tin t\u01b0\u1edfng\t r\u1eb1ng\t kh\u00f4ng\t gian\t Minkowski\t \\\"v\u00f4\t tr\u01b0\u1eddng\\\"\t v\u1edbi\t metric\t ph\u00f9 h\u1ee3p\t v\u1edbi\t (1)\t ph\u1ea3i\t th\u1ecfa\t m\u00e3n\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t tr\u01b0\u1eddng\t t\u1ed5ng\t qu\u00e1t.\t T\u1eeb tr\u01b0\u1eddng\th\u1ee3p\t\u0111\u1eb7c\tbi\u1ec7t\tn\u00e0y\tch\u00fang\tta\tsuy\tra\t\u0111\u1ecbnh\tlu\u1eadt\th\u1ea5p\td\u1eabn\tb\u1eb1ng m\u1ed9t\ts\u1ef1\tkh\u00e1i\tqu\u00e1t\th\u00f3a\th\u1ea7u\tnh\u01b0\tkh\u00f4ng\tc\u00f3\tm\u1ed9t\ts\u1ef1\tt\u00f9y\tti\u1ec7n\tn\u00e0o.\tCon \u0111\u01b0\u1eddng\t ph\u00e1t\t tri\u1ec3n\t ti\u1ebfp\t c\u1ee7a\t l\u00fd\t thuy\u1ebft\t kh\u00f4ng\t \u0111\u01b0\u1ee3c\t x\u00e1c\t \u0111\u1ecbnh\t r\u00f5 h\u01b0\u1edbng\t l\u1eafm\t t\u1eeb\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng;\t trong\t m\u1ea5y\t th\u1eadp\t k\u1ef7\t qua\t c\u00f3 nhi\u1ec1u\t cu\u1ed9c\t th\u1eed\t nghi\u1ec7m\t theo\t nhi\u1ec1u\t h\u01b0\u1edbng\t kh\u00e1c\t nhau.\t \u0110i\u1ec3m chung\tt\u1ea5t\tc\u1ea3\tc\u00e1c\tth\u1ee9\tnghi\u1ec7m\tn\u00e0y\tl\u00e0\tquan\tni\u1ec7m\tc\u00e1i\tth\u1ef1c\tt\u1ea1i\tv\u1eadt\tl\u00fd nh\u01b0\tm\u1ed9t\ttr\u01b0\u1eddng,\t\u1edf\t\u0111\u00f3\ttr\u01b0\u1eddng\tn\u00e0y\tl\u00e0\ts\u1ef1\tkh\u00e1i\tqu\u00e1t\th\u00f3a\tc\u1ee7a\ttr\u01b0\u1eddng h\u1ea5p\td\u1eabn,\tv\u00e0\t\u0111\u1ecbnh\tlu\u1eadt\ttr\u01b0\u1eddng\tl\u00e0\ts\u1ef1\tkh\u00e1i\tqu\u00e1t\th\u00f3a\tc\u1ee7a\t\u0111\u1ecbnh\tlu\u1eadt\tv\u1ec1 tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn\t thu\u1ea7n\t t\u00fay.\t T\u00f4i\t tin\t l\u00fac\t n\u00e0y,\t r\u1eb1ng\t sau\t m\u1ed9t\t s\u1ef1\t m\u00f2 m\u1eabm\tk\u00e9o\td\u00e0i,\tt\u00f4i\t\u0111\u00e3\tt\u00ecm\tth\u1ea5y[91]\th\u00ecnh\td\u1ea1ng\tt\u1ef1\tnhi\u00ean\tnh\u1ea5t\tc\u1ee7a\ts\u1ef1 kh\u00e1i\t qu\u00e1t\t h\u00f3a\t n\u00e0y,\t nh\u01b0ng\t \u0111\u1ebfn\t nay\t t\u00f4i\t v\u1eabn\t ch\u01b0a\t th\u1ec3\t bi\u1ebft\t ch\u1eafc \u0111\u01b0\u1ee3c\t \u0111\u1ecbnh\t lu\u1eadt\t m\u1edf\t r\u1ed9ng\t n\u00e0y\t c\u00f3\t \u0111\u1ee9ng\t v\u1eefng\t tr\u01b0\u1edbc\t nh\u1eefng\t d\u1eef\t ki\u1ec7n c\u1ee7a\tth\u1ef1c\tnghi\u1ec7m\thay\tkh\u00f4ng. \u0110\u1ed1i\tv\u1edbi\tnh\u1eefng\tsuy\tngh\u0129\ttr\u00ean,\tv\u1ea5n\t\u0111\u1ec1\tc\u1ee7a\t\u0111\u1ecbnh\tlu\u1eadt\ttr\u01b0\u1eddng\t\u0111\u1eb7c bi\u1ec7t\t l\u00e0\t th\u1ee9\t y\u1ebfu.\t C\u00e2u\t h\u1ecfi\t ch\u00ednh\t y\u1ebfu\t hi\u1ec7n\t nay\t l\u00e0,\t m\u1ed9t\t l\u00fd\t thuy\u1ebft tr\u01b0\u1eddng\t c\u1ee7a\t m\u1ed9t\t lo\u1ea1i\t \u0111ang\t \u0111\u01b0\u1ee3c\t quan\t t\u00e2m\t t\u1edbi\t n\u00f3i\t chung\t c\u00f3\t th\u1ec3","d\u1eabn\t\u0111\u1ebfn\tth\u00e0nh\tc\u00f4ng\thay\tkh\u00f4ng.\t\u00dd\tn\u00f3i,\t\u0111\u00f3\tl\u00e0\tm\u1ed9t\tl\u00fd\tthuy\u1ebft\tc\u00f3\tkh\u1ea3 n\u0103ng\t m\u00f4\t t\u1ea3\t m\u1ed9t\t c\u00e1ch\t tr\u1ecdn\t v\u1eb9n\t c\u00e1i\t th\u1ef1c\t t\u1ea1i\t v\u1eadt\t l\u00fd,\t bao\t g\u1ed3m\t c\u1ea3 kh\u00f4ng\tgian\tb\u1ed1n\tchi\u1ec1u,\tb\u1eb1ng\tm\u1ed9t\ttr\u01b0\u1eddng.\tTh\u1ebf\th\u1ec7\thi\u1ec7n\tt\u1ea1i\tc\u1ee7a\tc\u00e1c nh\u00e0\t v\u1eadt\t l\u00fd\t nghi\u00eang\t v\u1ec1\t c\u00e2u\t tr\u1ea3\t l\u1eddi\t ph\u1ee7\t \u0111\u1ecbnh;\t d\u1ef1a\t tr\u00ean\t t\u00ecnh\t h\u00ecnh ph\u00e1t\t tri\u1ec3n\t hi\u1ec7n\t t\u1ea1i\t c\u1ee7a\t thuy\u1ebft\t l\u01b0\u1ee3ng\t t\u1eed,\t h\u1ecd\t tin\t r\u1eb1ng\t tr\u1ea1ng\t th\u00e1i c\u1ee7a\tm\u1ed9t\th\u1ec7\tth\u1ed1ng\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\t\u0111\u1eb7c\ttr\u01b0ng\tkh\u00f4ng\tph\u1ea3i\ttr\u1ef1c\tti\u1ebfp,\tm\u00e0 ch\u1ec9\tb\u1eb1ng\tcon\t\u0111\u01b0\u1eddng\tgi\u00e1n\tti\u1ebfp\tqua\tm\u1ed9t\ts\u1ef1\tx\u00e1c\tnh\u1eadn\tth\u1ed1ng\tk\u00ea\tc\u1ee7a c\u00e1c\tk\u1ebft\tqu\u1ea3\t\u0111o\t\u0111\u1ea1c\t\u0111\u01b0\u1ee3c\t\u1edf\th\u1ec7\tth\u1ed1ng.\tM\u1ed9t\ts\u1ef1\t\u0111oan\tch\u1eafc\t\u0111ang\tth\u1ecbnh h\u00e0nh,\tr\u1eb1ng\tb\u1ea3n\tch\u1ea5t\t\u0111\u00f4i\t(c\u1ea5u\ttr\u00fac\th\u1ea1t\tv\u00e0\ts\u00f3ng)\t\u0111\u00e3\t\u0111\u01b0\u1ee3c\tb\u1ea3o\t\u0111\u1ea3m b\u1edfi\t th\u1ef1c\t nghi\u1ec7m\t ch\u1ec9\t c\u00f3\t th\u1ec3\t \u0111\u1ea1t\t \u0111\u01b0\u1ee3c\t b\u1eb1ng\t s\u1ef1\t gi\u1ea3m\t nh\u1eb9\t \u0111i\t kh\u00e1i ni\u1ec7m\tth\u1ef1c\tt\u1ea1i.\tT\u00f4i\tngh\u0129,\tm\u1ed9t\ts\u1ef1\tt\u1eeb\tch\u1ed1i\tr\u1ed9ng\tr\u00e3i\tnh\u01b0\tth\u1ebf\tv\u1ec1\tm\u1eb7t\tl\u00fd thuy\u1ebft\td\u1ef1a\ttr\u00ean\tki\u1ebfn\tth\u1ee9c\thi\u1ec7n\th\u00e0nh\tl\u00e0\tkh\u00f4ng\tth\u1ec3\tbi\u1ec7n\tgi\u1ea3i\t\u0111\u01b0\u1ee3c tr\u01b0\u1edbc\t m\u1eaft,\t v\u00e0\t ng\u01b0\u1eddi\t ta\t kh\u00f4ng\t n\u00ean\t \u0111\u1ec3\t m\u00ecnh\t b\u1ecb\t c\u1ea3n\t tr\u1edf\t trong\t vi\u1ec7c suy\tngh\u0129\t\u0111\u1ebfn\tc\u00f9ng\tv\u1ec1\tcon\t\u0111\u01b0\u1eddng\tc\u1ee7a\tthuy\u1ebft\ttr\u01b0\u1eddng\tt\u01b0\u01a1ng\t\u0111\u1ed1i.","T\u01af\tLI\u1ec6U\tL\u1ecaCH\tS\u1eec Ph\u1ea7n\tn\u00e0y\tkh\u00f4ng\tn\u1eb1m\ttrong\tquy\u1ec3n\ts\u00e1ch\tc\u1ee7a\tEinstein,\tm\u00e0\tdo\td\u1ecbch gi\u1ea3\t s\u01b0u\t t\u1ea7m\t v\u00e0\t th\u00eam\t v\u00e0o\t cho\t phong\t ph\u00fa.\t N\u00f3\t bao\t g\u1ed3m\t c\u00e1c\t b\u00e0i ph\u00e1t\t bi\u1ec3u\t hay\t vi\u1ebft\t c\u1ee7a\t Einstein\t v\u1ec1\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t c\u00f9ng\t nh\u01b0 c\u1ee7a\t c\u00e1c\t t\u00e1c\t gi\u1ea3\t kh\u00e1c\t xung\t quanh\t ch\u1ee7\t \u0111\u1ec1\t n\u00e0y,\t c\u00f3\t gi\u00e1\t tr\u1ecb\t l\u1ecbch\t s\u1eed c\u0169ng\tnh\u01b0\tnh\u1eadn\tth\u1ee9c\tlu\u1eadn. 1.\tAlbert\tEinstein V\u1ec1\t\u0110i\u1ec7n\t\u0110\u1ed9ng\tH\u1ecdc\tc\u1ee7a\tc\u00e1c\tV\u1eadt\tTh\u1ec3\tChuy\u1ec3n\t\u0110\u1ed9ng\t(1905) \u0110\u00e2y\t l\u00e0\t ph\u1ea7n\t \u0111\u1ea7u\t c\u1ee7a\t b\u00e0i\t b\u00e1o\t n\u1ed5i\t ti\u1ebfng\t v\u1ec1\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p v\u1edbi\tt\u1ef1a\t\u0111\u1ec1\tnh\u01b0\ttr\u00ean,\tti\u1ebfng\t\u0110\u1ee9c:\t\\\"Zur\tElektrodynamik\tbewegter K\u00f6rper\\\",\t m\u1ed9t\t trong\t n\u0103m\t b\u00e0i\t c\u1ee7a\t \\\"n\u0103m\t th\u1ea7n\t k\u1ef3\\\"\t 1905,\t \u0111\u01b0\u1ee3c \u0111\u0103ng\t trong\t t\u1ea1p\t ch\u00ed\t Annalen\t der\t Physik,\t t\u1eadp\t 17.\t Ch\u00fang\t ta\t h\u00e3y \\\"g\u1eb7p\\\"\t tr\u1ef1c\t ti\u1ebfp\t thanh\t ni\u00ean\t Einstein\t 26\t tu\u1ed5i\t \u00edt\t ph\u00fat\t qua\t ph\u1ea7n \u0111\u1ea7u\tc\u1ee7a\tb\u00e0i\tb\u00e1o\thuy\u1ec1n\ttho\u1ea1i\tn\u00e0y. Ng\u01b0\u1eddi\t ta\t bi\u1ebft\t r\u1eb1ng\t \u0111i\u1ec7n\t \u0111\u1ed9ng\t h\u1ecdc\t c\u1ee7a\t Maxwell\t -\t nh\u01b0\t hi\u1ec7n\t t\u1ea1i n\u00f3\t th\u01b0\u1eddng\t \u0111\u01b0\u1ee3c\t hi\u1ec3u\t -\t khi\t \u0111\u01b0\u1ee3c\t \u00e1p\t d\u1ee5ng\t v\u00e0o\t c\u00e1c\t v\u1eadt\t th\u1ec3\t chuy\u1ec3n \u0111\u1ed9ng,\td\u1eabn\tt\u1edbi\tc\u00e1c\tb\u1ea5t\t\u0111\u1ed1i\tx\u1ee9ng,\t\u0111i\u1ec1u\td\u01b0\u1eddng\tnh\u01b0\tkh\u00f4ng\tn\u1eb1m\ttrong b\u1ea3n\tch\u1ea5t\tc\u1ee7a\tc\u00e1c\thi\u1ec7n\tt\u01b0\u1ee3ng.\tTh\u00ed\td\u1ee5,\th\u00e3y\tngh\u0129\t\u0111\u1ebfn\tt\u00e1c\td\u1ee5ng\tqua l\u1ea1i\t \u0111i\u1ec7n\t \u0111\u1ed9ng\t h\u1ecdc\t gi\u1eefa\t m\u1ed9t\t thanh\t nam\t ch\u00e2m\t v\u00e0\t m\u1ed9t\t d\u00e2y\t d\u1eabn \u0111i\u1ec7n.\t Hi\u1ec7n\t t\u01b0\u1ee3ng\t quan\t s\u00e1t\t \u0111\u01b0\u1ee3c\t \u1edf\t \u0111\u00e2y\t ch\u1ec9\t l\u1ec7\t thu\u1ed9c\t v\u00e0o\t chuy\u1ec3n \u0111\u1ed9ng\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tc\u1ee7a\td\u00e2y\t\u0111i\u1ec7n\tv\u00e0\tthanh\tnam\tch\u00e2m,\ttrong\tkhi\ttheo c\u00e1ch\t hi\u1ec3u\t th\u00f4ng\t th\u01b0\u1eddng\t ng\u01b0\u1eddi\t ta\t l\u1ea1i\t ph\u00e2n\t bi\u1ec7t\t nghi\u00eam\t ng\u1eb7t\t hai tr\u01b0\u1eddng\t h\u1ee3p,\t m\u1ed9t\t v\u1eadt\t th\u1ec3\t n\u00e0y\t hay\t v\u1eadt\t th\u1ec3\t kia\t chuy\u1ec3n\t \u0111\u1ed9ng.\t Th\u1eadt v\u1eady,\t n\u1ebfu\t thanh\t nam\t ch\u00e2m\t chuy\u1ec3n\t \u0111\u1ed9ng,\t v\u00e0\t d\u00e2y\t \u0111i\u1ec7n\t \u0111\u1ee9ng\t y\u00ean, th\u00ec\t trong\t v\u00f9ng\t l\u00e2n\t c\u1eadn\t c\u1ee7a\t thanh\t nam\t ch\u00e2m\t s\u1ebd\t h\u00ecnh\t th\u00e0nh\t m\u1ed9t \u0111i\u1ec7n\t tr\u01b0\u1eddng\t v\u1edbi\t m\u1ed9t\t tr\u1ecb\t s\u1ed1\t n\u0103ng\t l\u01b0\u1ee3ng\t nh\u1ea5t\t \u0111\u1ecbnh,\t g\u00e2y\t ra\t m\u1ed9t d\u00f2ng\t\u0111i\u1ec7n\tt\u1ea1i\tnh\u1eefng\tn\u01a1i\tc\u00f3\tc\u00e1c\tph\u1ea7n\tc\u1ee7a\td\u00e2y\t\u0111i\u1ec7n\t\u0111ang\t\u1edf\t.\tNh\u01b0ng n\u1ebfu\tthanh\tnam\tch\u00e2m\t\u0111\u1ee9ng\ty\u00ean\tv\u00e0\td\u00e2y\t\u0111i\u1ec7n\tchuy\u1ec3n\t\u0111\u1ed9ng,\tth\u00ec\ts\u1ebd kh\u00f4ng\t c\u00f3\t \u0111i\u1ec7n\t tr\u01b0\u1eddng\t ph\u00e1t\t sinh\t trong\t v\u00f9ng\t l\u00e2n\t c\u1eadn\t c\u1ee7a\t nam ch\u00e2m.\t Tuy\t nhi\u00ean\t trong\t d\u00e2y\t \u0111i\u1ec7n\t c\u00f3\t ph\u00e1t\t sinh\t m\u1ed9t\t l\u1ef1c\t \u0111\u1ed9ng\t c\u01a1 \u0111i\u1ec7n,\t tuy\t kh\u00f4ng\t t\u01b0\u01a1ng\t \u1ee9ng\t v\u1edbi\t m\u1ed9t\t n\u0103ng\t l\u01b0\u1ee3ng,\t nh\u01b0ng\t n\u00f3\t l\u00e0m ph\u00e1t\t sinh\t m\u1ed9t\t d\u00f2ng\t \u0111i\u1ec7n\t c\u00f3\t c\u00f9ng\t c\u01b0\u1eddng\t \u0111\u1ed9,\t v\u00e0\t theo\t \u0111\u00fang\t qu\u00e1 tr\u00ecnh\t nh\u01b0\t c\u00e1c\t d\u00f2ng\t \u0111i\u1ec7n\t \u0111\u01b0\u1ee3c\t sinh\t ra\t b\u1edfi\t c\u00e1c\t l\u1ef1c\t \u0111i\u1ec7n\t trong","tr\u01b0\u1eddng\th\u1ee3p\tth\u1ee9\tnh\u1ea5t\t-\tn\u1ebfu\tch\u00fang\tta\tgi\u1ea3\tthi\u1ebft\ts\u1ef1\tt\u01b0\u01a1ng\t\u0111\u01b0\u01a1ng\tc\u1ee7a chuy\u1ec3n\t\u0111\u1ed9ng\tt\u01b0\u01a1ng\t\u0111\u1ed1i\t\u1edf\thai\ttr\u01b0\u1eddng\th\u1ee3p\t\u0111ang\tx\u00e9t. C\u00e1c\t th\u00ed\t nghi\u1ec7m\t lo\u1ea1i\t t\u01b0\u01a1ng\t t\u1ef1,\t c\u0169ng\t nh\u01b0\t c\u00e1c\t n\u1ed7\t l\u1ef1c\t kh\u00f4ng th\u00e0nh\t nh\u1eb1m\t ph\u00e1t\t hi\u1ec7n\t m\u1ed9t\t s\u1ef1\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t qu\u1ea3\t \u0111\u1ea5t\t \u0111\u1ed1i\t v\u1edbi \\\"m\u00f4i\ttr\u01b0\u1eddng\tc\u1ee7a\t\u00e1nh\ts\u00e1ng\\\",\tg\u1ee3i\tra\tr\u1eb1ng\tc\u00e1c\thi\u1ec7n\tt\u01b0\u1ee3ng\ttrong\t\u0111i\u1ec7n \u0111\u1ed9ng\t h\u1ecdc\t c\u0169ng\t nh\u01b0\t c\u01a1\t h\u1ecdc\t kh\u00f4ng\t h\u1ec1\t c\u00f3\t nh\u1eefng\t t\u00ednh\t ch\u1ea5t\t t\u01b0\u01a1ng \u1ee9ng\tv\u1edbi\t\u00fd\tt\u01b0\u1edfng\tv\u1ec1\ts\u1ef1\ty\u00ean\tt\u0129nh\ttuy\u1ec7t\t\u0111\u1ed1i,\tm\u00e0\t\u0111\u00fang\th\u01a1n\tch\u00fang\tg\u1ee3i ra\tr\u1eb1ng,\t\u0111\u1ed1i\tv\u1edbi\tt\u1ea5t\tc\u1ea3\tc\u00e1c\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tm\u00e0\t\u1edf\t\u0111\u00f3\tc\u00e1c\tph\u01b0\u01a1ng\ttr\u00ecnh\tc\u01a1 h\u1ecdc\t \u0111\u00e3\t c\u00f3\t hi\u1ec7u\t l\u1ef1c\t th\u00ec\t c\u00f9ng\t nh\u1eefng\t \u0111\u1ecbnh\t lu\u1eadt\t \u0111i\u1ec7n\t \u0111\u1ed9ng\t h\u1ecdc\t v\u00e0 quang\t h\u1ecdc\t c\u0169ng\t \u0111\u1ec1u\t c\u00f3\t hi\u1ec7u\t l\u1ef1c,\t nh\u01b0\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t ch\u1ee9ng\t minh\t cho c\u00e1c\t\u0111\u1ea1i\tl\u01b0\u1ee3ng\tb\u1eadc\tnh\u1ea5t.\tCh\u00fang\tta\tmu\u1ed1n\tn\u00e2ng\tgi\u1ea3\tthuy\u1ebft\tn\u00e0y\t(m\u00e0 n\u1ed9i\tdung\ts\u1ebd\t\u0111\u01b0\u1ee3c\tg\u1ecdi\tl\u00e0\t\\\"Nguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\\\"\tsau\t\u0111\u00e2y)\tl\u00ean\tth\u00e0nh m\u1ed9t\t \u0111\u1ecbnh\t \u0111\u1ec1,\t v\u00e0\t ngo\u00e0i\t ra\t \u0111\u01b0a\t v\u00e0o\t m\u1ed9t\t \u0111\u1ecbnh\t \u0111\u1ec1\t kh\u00e1c\t c\u00f3\t v\u1ebb\t nh\u01b0 kh\u00f4ng\tdung\th\u1ee3p\tv\u1edbi\tn\u00f3,\t\u0111\u00f3\tl\u00e0\t\u00e1nh\ts\u00e1ng\t\u0111\u01b0\u1ee3c\ttruy\u1ec1n\ttrong\tkh\u00f4ng gian\t r\u1ed7ng\t lu\u00f4n\t lu\u00f4n\t v\u1edbi\t m\u1ed9t\t v\u1eadn\t t\u1ed1c\t nh\u1ea5t\t \u0111\u1ecbnh\t c\t [92],\t \u0111\u1ed9c\t l\u1eadp\t v\u1edbi tr\u1ea1ng\tth\u00e1i\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tv\u1eadt\tth\u1ec3\tph\u00e1t\tra\tn\u00f3. Hai\t\u0111\u1ecbnh\t\u0111\u1ec1\tn\u00e0y\t\u0111\u1ee7\ts\u1ee9c\t\u0111\u1ec3\tthi\u1ebft\tl\u1eadp\tn\u00ean\tm\u1ed9t\tl\u00fd\tthuy\u1ebft\t\u0111\u01a1n\tgi\u1ea3n v\u00e0\tnh\u1ea5t\tqu\u00e1n\tc\u1ee7a\t\u0111i\u1ec7n\t\u0111\u1ed9ng\th\u1ecdc\tc\u1ee7a\tc\u00e1c\tv\u1eadt\tth\u1ec3\tchuy\u1ec3n\t\u0111\u1ed9ng\td\u1ef1a tr\u00ean\t n\u1ec1n\t t\u1ea3ng\t c\u1ee7a\t thuy\u1ebft\t Maxwell\t cho\t c\u00e1c\t v\u1eadt\t th\u1ec3\t \u0111\u1ee9ng\t y\u00ean.\t S\u1ef1 \u0111\u01b0a\tv\u00e0o\tgi\u1ea3\tthuy\u1ebft\t\\\"ether\tc\u1ee7a\t\u00e1nh\ts\u00e1ng\\\"\tt\u1ecf\tra\tl\u00e0\tth\u1eeba,\tb\u1edfi\tc\u00e1c\tsuy ngh\u0129\ts\u1ebd\t\u0111\u01b0\u1ee3c\tph\u00e1t\ttri\u1ec3n\t\u1edf\t\u0111\u00e2y\tkh\u00f4ng\t\u0111\u00f2i\th\u1ecfi\tm\u1ed9t\t\\\"kh\u00f4ng\tgian\ty\u00ean t\u0129nh\t tuy\u1ec7t\t \u0111\u1ed1i\\\"\t v\u1edbi\t nh\u1eefng\t t\u00ednh\t ch\u1ea5t\t \u0111\u1eb7c\t bi\u1ec7t\t n\u00e0o,\t ch\u00fang\t c\u0169ng kh\u00f4ng\tg\u00e1n\tm\u1ed9t\tv\u00e9ct\u01a1\tv\u1eadn\tt\u1ed1c\tcho\tm\u1ed9t\t\u0111i\u1ec3m\tn\u00e0o\tc\u1ee7a\tkh\u00f4ng\tgian r\u1ed7ng\tm\u00e0\t\u1edf\t\u0111\u00f3\tc\u00e1c\tqu\u00e1\ttr\u00ecnh\t\u0111i\u1ec7n\tt\u1eeb\tdi\u1ec5n\tra. C\u00f9ng\tnh\u01b0\tt\u1ea5t\tc\u1ea3\tc\u00e1c\tthuy\u1ebft\t\u0111i\u1ec7n\t\u0111\u1ed9ng\th\u1ecdc\tkh\u00e1c,\tl\u00fd\tthuy\u1ebft\t\u0111\u01b0\u1ee3c ph\u00e1t\t tri\u1ec3n\t \u1edf\t \u0111\u00e2y\t \u0111\u01b0\u1ee3c\t d\u1ef1a\t tr\u00ean\t \u0111\u1ed9ng\t h\u1ecdc\t c\u1ee7a\t v\u1eadt\t th\u1ec3\t r\u1eafn,\t b\u1edfi\t v\u00ec c\u00e1c\tm\u1ec7nh\t\u0111\u1ec1\t(\u0111\u1ecbnh\tl\u00fd)\tc\u1ee7a\tb\u1ea5t\tc\u1ee9\tm\u1ed9t\tl\u00fd\tthuy\u1ebft\tn\u00e0o\tnh\u01b0\tth\u1ebf\t\u0111\u1ec1u li\u00ean\t can\t \u0111\u1ebfn\t c\u00e1c\t m\u1ed1i\t quan\t h\u1ec7\t gi\u1eefa\t c\u00e1c\t v\u1eadt\t th\u1ec3\t r\u1eafn\t (h\u1ec7\t t\u1ecda\t \u0111\u1ed9), \u0111\u1ed3ng\th\u1ed3\tv\u00e0\tc\u00e1c\tqu\u00e1\ttr\u00ecnh\t\u0111i\u1ec7n\tt\u1eeb\th\u1ecdc.\tS\u1ef1\tquan\tt\u00e2m\tkh\u00f4ng\t\u0111\u1ea7y\t\u0111\u1ee7 \u0111\u1ebfn\tt\u00ecnh\thu\u1ed1ng\tn\u00e0y\tch\u00ednh\tl\u00e0\tngu\u1ed3n\tg\u1ed1c\tc\u1ee7a\tnh\u1eefng\tkh\u00f3\tkh\u0103n\tm\u00e0 \u0111i\u1ec7n\t \u0111\u1ed9ng\t h\u1ecdc\t c\u1ee7a\t c\u00e1c\t v\u1eadt\t th\u1ec3\t chuy\u1ec3n\t \u0111\u1ed9ng\t hi\u1ec7n\t nay\t ph\u1ea3i\t chi\u1ebfn \u0111\u1ea5u. Ph\u1ea7n\t\u0110\u1ed9ng\tH\u1ecdc \u00a7\t1.\t\u0110\u1ecbnh\tngh\u0129a\tc\u1ee7a\tt\u00ednh\t\u0111\u1ed3ng\tth\u1eddi Ch\u00fang\tta\th\u00e3y\tl\u1ea5y\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tm\u00e0\t\u1edf\t\u0111\u00f3\tc\u00e1c\tph\u01b0\u01a1ng\ttr\u00ecnh\tc\u1ee7a","c\u01a1\t h\u1ecdc\t Newton\t c\u00f3\t hi\u1ec7u\t l\u1ef1c.\t \u0110\u1ec3\t c\u00f3\t s\u1ef1\t ph\u00e2n\t bi\u1ec7t\t v\u1ec1\t m\u1eb7t\t ng\u00f4n\t ng\u1eef \u0111\u1ed1i\t v\u1edbi\t c\u00e1c\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t s\u1ebd\t \u0111\u01b0\u1ee3c\t \u0111\u1ec1\t c\u1eadp\t \u0111\u1ebfn\t sau\t n\u00e0y,\t v\u00e0\t \u0111\u1ec3\t cho\t s\u1ef1 tr\u00ecnh\t b\u00e0y\t \u0111\u01b0\u1ee3c\t ch\u00ednh\t x\u00e1c\t h\u01a1n,\t ch\u00fang\t ta\t g\u1ecdi\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t n\u00e0y\t l\u00e0\t \\\"h\u1ec7 t\u1ecda\t\u0111\u1ed9\t\u0111\u1ee9ng\ty\u00ean\\\". N\u1ebfu\t m\u1ed9t\t \u0111i\u1ec3m\t v\u1eadt\t ch\u1ea5t\t \u0111\u1ee9ng\t y\u00ean\t \u0111\u1ed1i\t v\u1edbi\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t n\u00e0y\t th\u00ec\t v\u1ecb tr\u00ed\t c\u1ee7a\t n\u00f3\t trong\t \u0111\u00f3\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t x\u00e1c\t \u0111\u1ecbnh\t b\u1eb1ng\t c\u00e1ch\t s\u1eed\t d\u1ee5ng\t c\u00e1c th\u01b0\u1edbc\t\u0111o\tr\u1eafn,\tc\u00e1c\tph\u01b0\u01a1ng\tph\u00e1p\tc\u1ee7a\th\u00ecnh\th\u1ecdc\tEuclid,\tv\u00e0\t\u0111\u01b0\u1ee3c\tdi\u1ec5n t\u1ea3\tb\u0103ng\tc\u00e1c\tt\u1ecda\t\u0111\u1ed9\tDescartes. N\u1ebfu\tmu\u1ed1n\tm\u00f4\tt\u1ea3\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tm\u1ed9t\t\u0111i\u1ec3m\tv\u1eadt\tch\u1ea5t,\tch\u00fang\tta cho\t nh\u1eefng\t tr\u1ecb\t s\u1ed1\t t\u1ecda\t \u0111\u1ed9\t c\u1ee7a\t n\u00f3\t nh\u01b0\t l\u00e0\t h\u00e0m\t s\u1ed1\t c\u1ee7a\t th\u1eddi\t gian. Nh\u01b0ng\t ch\u00fang\t ph\u1ea3i\t c\u1ea9n\t th\u1eadn\t \u0111\u1ec3\t \u00fd\t r\u1eb1ng\t m\u1ed9t\t s\u1ef1\t m\u00f4\t t\u1ea3\t to\u00e1n\t h\u1ecdc nh\u01b0\tth\u1ebf\tch\u1ec9\tc\u00f3\t\u00fd\tngh\u0129a\tkhi\tch\u00fang\tta\t\u0111\u00e3\th\u00ecnh\tdung\tr\u00f5\t\\\"th\u1eddi\tgian\\\"\t\u1edf \u0111\u00e2y\tl\u00e0\tg\u00ec.\tC\u1ea7n\t\u0111\u1ec1\t\u00fd\tr\u1eb1ng\tt\u1ea5t\tc\u1ea3\tnh\u1eefng\tph\u00e1n\t\u0111o\u00e1n\tc\u1ee7a\tch\u00fang\tta\tm\u00e0 trong\t \u0111\u00f3\t th\u1eddi\t gian\t c\u00f3\t m\u1ed9t\t vai\t tr\u00f2\t \u0111\u1ec1u\t l\u00e0\t nh\u1eefng\t ph\u00e1n\t \u0111o\u00e1n\t v\u1ec1 nh\u1eefng\ts\u1ef1\tki\u1ec7n\t\u0111\u1ed3ng\tth\u1eddi.\tCh\u1eb3ng\th\u1ea1n,\tkhi\tt\u00f4i\tn\u00f3i\tr\u1eb1ng\t\\\"chi\u1ebfc\txe\tl\u1eeda kia\t \u0111\u1ebfn\t \u0111\u00e2y\t v\u00e0o\t l\u00fac\t 7\t gi\u1edd\\\",\t th\u00ec\t \u0111i\u1ec1u\t n\u00e0y\t c\u00f3\t ngh\u0129a\t nh\u01b0\t sau:\t \\\"C\u00e2y kim\tch\u1ec9\tgi\u1edd\tc\u1ee7a\tchi\u1ebfc\t\u0111\u1ed3ng\th\u1ed3\tt\u00f4i\tch\u1ec9\ts\u1ed1\t7,\tv\u00e0\ts\u1ef1\txu\u1ea5t\thi\u1ec7n\tc\u1ee7a\txe l\u1eeda\t\u1edf\t\u0111\u00e2y,\t\u0111\u00f3\tl\u00e0\tnh\u1eefng\ts\u1ef1\tki\u1ec7n\t\u0111\u1ed3ng\tth\u1eddi\\\". C\u00f3\t th\u1ec3\t ng\u01b0\u1eddi\t ta\t ngh\u0129\t r\u1eb1ng\t t\u1ea5t\t c\u1ea3\t nh\u1eefng\t kh\u00f3\t kh\u0103n\t li\u00ean\t quan \u0111\u1ebfn\t \u0111\u1ecbnh\t ngh\u0129a\t \\\"th\u1eddi\t gian\\\"\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t kh\u1eafc\t ph\u1ee5c,\t n\u1ebfu\t ch\u00fang\t ta thay\tth\u1ebf\t\\\"th\u1eddi\tgian\\\"\tb\u1eb1ng\t\\\"v\u1ecb\ttr\u00ed\tc\u00e2y\tkim\tch\u1ec9\tgi\u1edd\tc\u1ee7a\t\u0111\u1ed3ng\th\u1ed3\tt\u00f4i\\\". M\u1ed9t\t\u0111\u1ecbnh\tngh\u0129a\tnh\u01b0\tth\u1ebf\tth\u1ef1c\tt\u1ebf\tl\u00e0\tth\u1ecfa\t\u0111\u00e1ng,\tn\u1ebfu\tch\u00fang\tta\tmu\u1ed1n \u0111\u1ecbnh\tngh\u0129a\tth\u1eddi\tgian\tch\u1ec9\tcho\tt\u1ea1i\tn\u01a1i\t\u0111\u1ed3ng\th\u1ed3\t\u0111ang\t\u0111\u01b0\u1ee3c\t\u0111\u1eb7t\tth\u00f4i; nh\u01b0ng\t \u0111\u1ecbnh\t ngh\u0129a\t \u0111\u00f3\t s\u1ebd\t kh\u00f4ng\t th\u1ecfa\t \u0111\u00e1ng\t n\u1ebfu\t ph\u1ea3i\t li\u00ean\t k\u1ebft\t v\u1edbi nhau\t v\u1ec1\t m\u1eb7t\t th\u1eddi\t gian\t c\u00e1c\t chu\u1ed7i\t s\u1ef1\t ki\u1ec7n\t x\u1ea3y\t ra\t t\u1ea1i\t nhi\u1ec1u\t v\u1ecb\t tr\u00ed kh\u00e1c\t nhau\t -\t hay\t m\u1ed9t\t c\u00e1ch\t t\u01b0\u01a1ng\t \u0111\u01b0\u01a1ng\t -\t n\u1ebfu\t ch\u00fang\t ta\t ph\u1ea3i\t \u0111o th\u1eddi\tgian\tc\u1ee7a\tc\u00e1c\ts\u1ef1\tki\u1ec7n\tx\u1ea3y\tra\tt\u1ea1i\tnh\u1eefng\tn\u01a1i\txa\t\u0111\u1ed3ng\th\u1ed3. Ch\u00fang\t ta\t d\u0129\t nhi\u00ean\t c\u00f3\t th\u1ec3\t b\u1eb1ng\t l\u00f2ng\t v\u1edbi\t c\u00e1c\t tr\u1ecb\t s\u1ed1\t th\u1eddi\t gian \u0111\u01b0\u1ee3c\t x\u00e1c\t \u0111\u1ecbnh\t b\u1edfi\t m\u1ed9t\t quan\t s\u00e1t\t vi\u00ean\t \u0111\u01b0\u1ee3c\t \u0111\u1eb7t\t c\u00f9ng\t v\u1edbi\t \u0111\u1ed3ng\t h\u1ed3 t\u1ea1i\t \u0111i\u1ec3m\t g\u1ed1c\t c\u1ee7a\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9,\t ghi\t nh\u1eadn\t c\u00e1c\t v\u1ecb\t tr\u00ed\t c\u1ee7a\t kim\t ch\u1ec9\t gi\u1edd t\u01b0\u01a1ng\t\u1ee9ng\tv\u1edbi\tt\u00edn\thi\u1ec7u\t\u00e1nh\ts\u00e1ng\t\u0111\u01b0\u1ee3c\tph\u00e1t\tra\tt\u1eeb\tm\u1ed7i\ts\u1ef1\tki\u1ec7n\tc\u1ea7n \u0111\u01b0\u1ee3c\t\u0111o\tth\u1eddi\tgian,\tv\u00e0\t\u0111\u1ebfn\tv\u1edbi\tanh\tta,\tsau\tkhi\t\u0111i\txuy\u00ean\tqua\tkh\u00f4ng gian\t r\u1ed7ng.\t Nh\u01b0ng\t ph\u00e9p\t t\u01b0\u01a1ng\t \u1ee9ng\t \u1ea5y\t (v\u1ecb\t tr\u00ed\t kim\t ch\u1ec9\t gi\u1edd\t v\u00e0\t t\u00edn hi\u1ec7u\t\u00e1nh\ts\u00e1ng\t\u0111\u1ebfn)\tmang\ttheo\tm\u1ed9t\tb\u1ea5t\tl\u1ee3i,\tr\u1eb1ng\tn\u00f3\tkh\u00f4ng\t\u0111\u1ed9c\tl\u1eadp v\u1edbi\tquan\t\u0111i\u1ec3m\tc\u1ee7a\tng\u01b0\u1eddi\tquan\ts\u00e1t\t\u0111\u01b0\u1ee3c\ttrang\tb\u1ecb\tv\u1edbi\tc\u00e1i\t\u0111\u1ed3ng\th\u1ed3, nh\u01b0\t ch\u00fang\t ta\t bi\u1ebft\t qua\t kinh\t nghi\u1ec7m.\t Ch\u00fang\t ta\t \u0111\u1ea1t\t \u0111\u1ebfn\t m\u1ed9t\t quy \u0111\u1ecbnh\tth\u1ef1c\tt\u1ebf\th\u01a1n\tr\u1ea5t\tnhi\u1ec1u\tqua\tc\u00e1ch\tsuy\tngh\u0129\tsau\t\u0111\u00e2y.","N\u1ebfu\tt\u1ea1i\t\u0111i\u1ec3m\tA\tc\u1ee7a\tkh\u00f4ng\tgian\tc\u00f3\t\u0111\u1eb7t\tm\u1ed9t\tc\u00e1i\t\u0111\u1ed3ng\th\u1ed3,\tth\u00ec\tm\u1ed9t ng\u01b0\u1eddi\t quan\t s\u00e1t\t t\u1ea1i\t A\t c\u00f3\t th\u1ec3\t x\u00e1c\t \u0111\u1ecbnh\t th\u1eddi\t gian\t c\u1ee7a\t nh\u1eefng\t hi\u1ec7n t\u01b0\u1ee3ng\tx\u1ea3y\tra\ttrong\tv\u00f9ng\tl\u00e2n\tc\u1eadn\ttr\u1ef1c\tti\u1ebfp,\tb\u1eb1ng\tc\u00e1ch\tx\u00e1c\t\u0111\u1ecbnh\tc\u00e1c v\u1ecb\t tr\u00ed\t c\u1ee7a\t kim\t ch\u1ec9\t gi\u1edd\t di\u1ec5n\t ra\t \u0111\u1ed3ng\t th\u1eddi\t v\u1edbi\t c\u00e1c\t s\u1ef1\t ki\u1ec7n.\t N\u1ebfu\t t\u1ea1i \u0111i\u1ec3m\tB\ttrong\tkh\u00f4ng\tgian\tc\u0169ng\tc\u00f3\tm\u1ed9t\tchi\u1ebfc\t\u0111\u1ed3ng\th\u1ed3,\tgi\u1ea3\tthi\u1ebft\tc\u00f3 c\u1ea5u\t t\u1ea1o\t ho\u00e0n\t to\u00e0n\t gi\u1ed1ng\t \u0111\u1ed3ng\t h\u1ed3\t \u1edf\t A,\t th\u00ec\t m\u1ed9t\t s\u1ef1\t x\u00e1c\t \u0111\u1ecbnh\t th\u1eddi gian\tc\u1ee7a\tnh\u1eefng\ts\u1ef1\tki\u1ec7n\tx\u1ea3y\tra\ttrong\tv\u00f9ng\tl\u00e2n\tc\u1eadn\ttr\u1ef1c\tti\u1ebfp\tc\u1ee7a\tB l\u00e0\t c\u00f3\t th\u1ec3\t qua\t m\u1ed9t\t ng\u01b0\u1eddi\t quan\t s\u00e1t\t \u0111\u1eb7t\t \u1edf\t B.\t Tuy\t nhi\u00ean,\t n\u1ebfu\t kh\u00f4ng c\u00f3\t gi\u1ea3\t thi\u1ebft\t g\u00ec\t kh\u00e1c\t n\u1eefa,\t ng\u01b0\u1eddi\t ta\t v\u1eabn\t ch\u01b0a\t th\u1ec3\t so\t s\u00e1nh\t v\u1ec1\t m\u1eb7t th\u1eddi\t gian\t m\u1ed9t\t s\u1ef1\t ki\u1ec7n\t t\u1ea1i\t A\t v\u1edbi\t m\u1ed9t\t s\u1ef1\t ki\u1ec7n\t t\u1ea1i\t B.\t Ch\u00fang\t ta\t \u0111\u1ebfn gi\u1edd\t ch\u1ec9\t m\u1edbi\t \u0111\u1ecbnh\t ngh\u0129a\t m\u1ed9t\t \\\"th\u1eddi\t gian-A\\\"\t v\u00e0\t m\u1ed9t\t \\\"th\u1eddi\t gian-B\\\", nh\u01b0ng\tch\u01b0a\tc\u00f3\t\\\"th\u1eddi\tgian\\\"\tchung\tcho\tA\tv\u00e0\tB.\tTh\u1eddi\tgian\tsau\tc\u00f3\tth\u1ec3 \u0111\u01b0\u1ee3c\t \u0111\u1ecbnh\t ngh\u0129a\t b\u1eb1ng\t c\u00e1ch\t ng\u01b0\u1eddi\t ta\t quy\t \u0111\u1ecbnh\t b\u1eb1ng\t \u0111\u1ecbnh\t ngh\u0129a, r\u1eb1ng\t\\\"th\u1eddi\tgian\\\"\tc\u1ea7n\tthi\u1ebft\t\u0111\u1ec3\t\u00e1nh\ts\u00e1ng\t\u0111i\tt\u1eeb\tA\t\u0111\u1ebfn\tB\tl\u00e0\tb\u1eb1ng\t\\\"th\u1eddi gian\\\"\t c\u1ea7n\t thi\u1ebft\t \u0111\u1ec3\t n\u00f3\t \u0111i\t t\u1eeb\t B\t sang\t A.\t H\u00e3y\t \u0111\u1ec3\t m\u1ed9t\t tia\t s\u00e1ng\t xu\u1ea5t ph\u00e1t\t t\u1eeb\t A\t v\u00e0o\t \\\"th\u1eddi\t gian-A\\\"\t l\u00e0\t tA\t \u0111\u1ec3\t \u0111i\t sang\t B,\t v\u00e0\t \u0111\u1ec3\t cho\t n\u00f3\t \u0111\u01b0\u1ee3c ph\u1ea3n\t chi\u1ebfu\t t\u1ea1i\t B\t v\u00e0o\t \\\"th\u1eddi\t gian-B\\\"\t l\u00e0\t tB\t \u0111i\t sang\t A,\t v\u00e0\t v\u1ec1\t l\u1ea1i\t A\t l\u00fac \\\"th\u1eddi\t gian-A\\\"\t t'.\t Theo\t \u0111\u1ecbnh\t ngh\u0129a,\t hai\t \u0111\u1ed3ng\t h\u1ed3\t \u0111\u01b0\u1ee3c\t g\u1ecdi\t l\u00e0\t ch\u1ea1y \u0111\u1ed3ng\tb\u1ed9\tv\u1edbi\tnhau,\tkhi tB\t\u2013\ttA\t=\tt'A\t\u2013\tt'B Ch\u00fang\t ta\t gi\u1ea3\t thi\u1ebft\t r\u1eb1ng\t \u0111\u1ecbnh\t ngh\u0129a\t n\u00e0y\t c\u1ee7a\t t\u00ednh\t \u0111\u1ed3ng\t b\u1ed9\t l\u00e0 kh\u00f4ng\t m\u00e2u\t thu\u1eabn,\t v\u00e0\t c\u00f3\t hi\u1ec7u\t l\u1ef1c\t cho\t b\u1ea5t\t k\u1ef3\t s\u1ed1\t \u0111i\u1ec3m,\t v\u00e0\t qua\t \u0111\u00f3 c\u00e1c\tt\u00ednh\tch\u1ea5t\tsau\t\u0111\u00e2y\t\u0111\u00fang\tm\u1ed9t\tc\u00e1ch\tph\u1ed5\tqu\u00e1t: 1.\tN\u1ebfu\t\u0111\u1ed3ng\th\u1ed3\t\u1edf\tB\tch\u1ea1y\t\u0111\u1ed3ng\tb\u1ed9\tv\u1edbi\t\u0111\u1ed3ng\th\u1ed3\t\u1edf\tA,\tth\u00ec\t\u0111\u1ed3ng\th\u1ed3\t\u1edf A\tch\u1ea1y\t\u0111\u1ed3ng\tb\u1ed9\tv\u1edbi\t\u0111\u1ed3ng\th\u1ed3\t\u1edf\tB. 2.\tN\u1ebfu\t\u0111\u1ed3ng\th\u1ed3\t\u1edf\tA\tch\u1ea1y\t\u0111\u1ed3ng\tb\u1ed9\tv\u1eeba\tv\u1edbi\t\u0111\u1ed3ng\th\u1ed3\t\u1edf\tB\tv\u00e0\t\u0111\u1ed3ng h\u1ed3\t\u1edf\tC,\tth\u00ec\t\u0111\u1ed3ng\th\u1ed3\t\u1edf\tB\tv\u00e0\tC\tc\u0169ng\tch\u1ea1y\t\u0111\u1ed3ng\tb\u1ed9\tnhau. V\u1edbi\t s\u1ef1\t h\u1ed7\t tr\u1ee3\t c\u1ee7a\t c\u00e1c\t th\u00ed\t nghi\u1ec7m\t v\u1eadt\t l\u00fd\t trong\t t\u01b0\u1edfng\t t\u01b0\u1ee3ng nh\u1ea5t\t \u0111\u1ecbnh,\t ch\u00fang\t ta\t \u0111\u00e3\t x\u00e1c\t \u0111\u1ecbnh\t \u0111\u01b0\u1ee3c\t th\u1ebf\t n\u00e0o\t l\u00e0\t c\u00e1c\t \u0111\u1ed3ng\t h\u1ed3 \u0111\u1ee9ng\ty\u00ean,\t\u0111\u01b0\u1ee3c\t\u0111\u1eb7t\tt\u1ea1i\tnhi\u1ec1u\tv\u1ecb\ttr\u00ed\tkh\u00e1c\tnhau\tch\u1ea1y\t\u0111\u1ed3ng\tb\u1ed9,\tv\u00e0\tr\u00f5 r\u00e0ng\t qua\t \u0111\u00f3\t ch\u00fang\t ta\t c\u00f3\t \u0111\u01b0\u1ee3c\t m\u1ed9t\t \u0111\u1ecbnh\t ngh\u0129a\t c\u1ee7a\t \\\"\u0111\u1ed3ng\t th\u1eddi\\\" hay\t \\\"\u0111\u1ed3ng\t b\u1ed9\\\"\t v\u00e0\t c\u1ee7a\t \\\"th\u1eddi\t gian\\\".\t \\\"Th\u1eddi\t gian\\\"\t c\u1ee7a\t m\u1ed9t\t s\u1ef1\t ki\u1ec7n\t l\u00e0 th\u1eddi\t gian\t \u0111\u1ed3ng\t th\u1eddi\t v\u1edbi\t s\u1ef1\t ki\u1ec7n\t c\u1ee7a\t m\u1ed9t\t \u0111\u1ed3ng\t h\u1ed3\t \u0111\u1ee9ng\t y\u00ean\t \u0111\u01b0\u1ee3c \u0111\u1eb7t\tt\u1ea1i\tch\u1ed7\tc\u1ee7a\ts\u1ef1\tki\u1ec7n,\tch\u1ea1y\t\u0111\u1ed3ng\tb\u1ed9\tv\u1edbi\tm\u1ed9t\t\u0111\u1ed3ng\th\u1ed3\t\u0111\u1ee9ng\ty\u00ean nh\u1ea5t\t \u0111\u1ecbnh,\t v\u00e0\t th\u1ef1c\t t\u1ebf\t ch\u1ea1y\t \u0111\u1ed3ng\t b\u1ed9\t \u1edf\t m\u1ecdi\t s\u1ef1\t x\u00e1c\t \u0111\u1ecbnh\t th\u1eddi\t gian v\u1edbi\t\u0111\u1ed3ng\th\u1ed3\t\u0111\u00e3\tn\u00f3i.","Th\u00eam\t n\u1eefa,\t ph\u00f9\t h\u1ee3p\t v\u1edbi\t kinh\t nghi\u1ec7m,\t ch\u00fang\t ta\t gi\u1ea3\t thi\u1ebft\t r\u1eb1ng \u0111\u1ea1i\tl\u01b0\u1ee3ng (AB\tl\u00e0\tkho\u1ea3ng\tc\u00e1ch\tgi\u1eefa\tA\tv\u00e0\tB) l\u00e0\t m\u1ed9t\t h\u1eb1ng\t s\u1ed1\t ph\u1ed5\t qu\u00e1t\t -\t v\u1eadn\t t\u1ed1c\t truy\u1ec1n\t c\u1ee7a\t \u00e1nh\t s\u00e1ng\t trong kh\u00f4ng\tgian\tr\u1ed7ng. \u0110i\u1ec1u\tc\u01a1\tb\u1ea3n\tl\u00e0\tch\u00fang\tta\t\u0111\u00e3\t\u0111\u1ecbnh\tngh\u0129a\tth\u1eddi\tgian\tb\u1eb1ng\tc\u00e1c\t\u0111\u1ed3ng h\u1ed3\t\u0111\u1ee9ng\ty\u00ean\ttrong\tm\u1ed9t\th\u1ec7\tth\u1ed1ng\t\u0111\u1ee9ng\ty\u00ean,\tv\u00e0\tch\u00fang\tta\tg\u1ecdi\tth\u1eddi gian\t v\u1eeba\t \u0111\u01b0\u1ee3c\t \u0111\u1ecbnh\t ngh\u0129a\t l\u00e0\t \\\"th\u1eddi\t gian\t c\u1ee7a\t h\u1ec7\t quy\t chi\u1ebfu\t \u0111\u1ee9ng y\u00ean\\\",\tb\u1edfi\tn\u00f3\tthu\u1ed9c\tv\u1ec1\th\u1ec7\tth\u1ed1ng\t\u0111\u1ee9ng\ty\u00ean. \u00a7\t2.\tV\u1ec1\tt\u00ednh\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tc\u1ee7a\tchi\u1ec1u\td\u00e0i\tv\u00e0\tth\u1eddi\tgian Nh\u1eefng\tsuy\tngh\u0129\tti\u1ebfp\ttheo\t\u0111\u00e2y\t\u0111\u01b0\u1ee3c\td\u1ef1a\ttr\u00ean\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng \u0111\u1ed1i\t v\u00e0\t nguy\u00ean\t l\u00fd\t h\u1eb1ng\t s\u1ed1\t c\u1ee7a\t v\u1eadn\t t\u1ed1c\t truy\u1ec1n\t \u00e1nh\t s\u00e1ng,\t c\u1ea3\t hai \u0111\u01b0\u1ee3c\tch\u00fang\tta\t\u0111\u1ecbnh\tngh\u0129a\tnh\u01b0\tsau: 1.\t C\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt,\t theo\t \u0111\u00f3\t c\u00e1c\t thay\t \u0111\u1ed5i\t tr\u1ea1ng\t th\u00e1i\t c\u1ee7a\t h\u1ec7\t th\u1ed1ng v\u1eadt\tl\u00fd\tb\u1ecb\tchi\tph\u1ed1i,\tl\u00e0\tkh\u00f4ng\th\u1ec1\tb\u1ecb\t\u1ea3nh\th\u01b0\u1edfng,\tcho\td\u00f9\tc\u00e1c\tthay\t\u0111\u1ed5i tr\u1ea1ng\t th\u00e1i\t n\u00e0y\t \u0111\u01b0\u1ee3c\t quy\t chi\u1ebfu\t l\u00ean\t m\u1ed9t\t trong\t hai\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t c\u00f3 chuy\u1ec3n\t\u0111\u1ed9ng\tt\u1ecbnh\tti\u1ebfn\t\u0111\u1ec1u\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tv\u1edbi\tnhau. 2.\tM\u1ed7i\ttia\ts\u00e1ng\tchuy\u1ec3n\t\u0111\u1ed9ng\ttrong\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\t\\\"y\u00ean\tt\u0129nh\\\"\tv\u1edbi v\u1eadn\tt\u1ed1c\tnh\u1ea5t\t\u0111\u1ecbnh\tc,\t\u0111\u1ed9c\tl\u1eadp\tv\u1edbi\tvi\u1ec7c\ttia\ts\u00e1ng\t\u0111\u01b0\u1ee3c\tph\u00e1t\tra\tb\u1edfi\tm\u1ed9t v\u1eadt\tth\u1ec3\t\u0111\u1ee9ng\ty\u00ean\thay\tchuy\u1ec3n\t\u0111\u1ed9ng.\t\u1ede\t\u0111\u00e2y trong\t\u0111\u00f3\t\\\"th\u1eddi\tgian\t\u0111i\\\"\t\u0111\u01b0\u1ee3c\thi\u1ec3u\tnh\u01b0\ttrong\t\u00a7\t1. Ch\u00fang\tta\th\u00e3y\tx\u00e9t\tm\u1ed9t\tthanh\tr\u1eafn\t\u0111\u1ee9ng\ty\u00ean;\tthanh\tn\u00e0y\tc\u00f3\tm\u1ed9t chi\u1ec1u\t d\u00e0i\t l\u00e0\t l\t n\u1ebfu\t \u0111\u01b0\u1ee3c\t \u0111o\t b\u1eb1ng\t m\u1ed9t\t th\u01b0\u1edbc\t \u0111o\t \u0111\u01a1n\t v\u1ecb\t c\u0169ng\t \u0111\u1ee9ng y\u00ean.\tCh\u00fang\tta\tt\u01b0\u1edfng\tt\u01b0\u1ee3ng\t\u0111\u1eb7t\ttr\u1ee5c\tc\u1ee7a\tthanh\tv\u00e0o\ttr\u1ee5c\tx\tc\u1ee7a\tm\u1ed9t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t \u0111\u1ee9ng\t y\u00ean,\t v\u00e0\t sau\t \u0111\u00f3\t t\u1ea1o\t cho\t thanh\t m\u1ed9t\t chuy\u1ec3n\t \u0111\u1ed9ng t\u1ecbnh\t ti\u1ebfn\t song\t song\t \u0111\u1ec1u\t v\u1edbi\t v\u1eadn\t t\u1ed1c\t l\u00e0\t v\t d\u1ecdc\t theo\t tr\u1ee5c\t x\t theo h\u01b0\u1edbng\t t\u0103ng\t c\u1ee7a\t x.\t Gi\u1edd\t ch\u00fang\t ta\t h\u1ecfi\t chi\u1ec1u\t d\u00e0i\t c\u1ee7a\t thanh\t chuy\u1ec3n \u0111\u1ed9ng\tm\u00e0\tch\u00fang\tta\tngh\u0129\ts\u1ebd\t\u0111\u01b0\u1ee3c\tx\u00e1c\t\u0111\u1ecbnh\tb\u1eb1ng\thai\tthao\tt\u00e1c\tsau: (a)\t Ng\u01b0\u1eddi\t quan\t s\u00e1t\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u00f9ng\t v\u1edbi\t m\u1ed9t\t th\u01b0\u1edbc\t \u0111o\t n\u00f3i","tr\u00ean\tv\u00e0\tv\u1edbi\tthanh\tc\u1ea7n\t\u0111o,\tanh\tta\t\u0111o\tchi\u1ec1u\td\u00e0i\tc\u1ee7a\tthanh\ttr\u1ef1c\tti\u1ebfp b\u1eb1ng\tc\u00e1ch\tch\u1eadp\tth\u01b0\u1edbc\t\u0111o\tl\u00ean,\ttheo\t\u0111\u00fang\tc\u00e1ch\tth\u1ee9c\tnh\u01b0\tkhi\tc\u1ea3\tba, thanh\t c\u1ea7n\t \u0111\u01b0\u1ee3c\t \u0111o,\t ng\u01b0\u1eddi\t quan\t s\u00e1t\t v\u00e0\t th\u01b0\u1edbc\t \u0111o,\t \u1edf\t trong\t tr\u1ea1ng th\u00e1i\t\u0111\u1ee9ng\ty\u00ean. (b)\t Ng\u01b0\u1eddi\t quan\t s\u00e1t\t -\t v\u1edbi\t s\u1ef1\t h\u1ed7\t tr\u1ee3\t c\u1ee7a\t c\u00e1c\t \u0111\u1ed3ng\t h\u1ed3\t \u0111\u1ee9ng\t y\u00ean, \u0111\u01b0\u1ee3c\t\u0111\u1ed3ng\tb\u1ed9\th\u00f3a\ttheo\t\u00a7\t1\tv\u00e0\t\u0111\u01b0\u1ee3c\t\u0111\u1eb7t\ttrong\th\u1ec7\tth\u1ed1ng\t\u0111\u1ee9ng\ty\u00ean\t- x\u00e1c\t \u0111\u1ecbnh\t t\u1ea1i\t nh\u1eefng\t \u0111i\u1ec3m\t n\u00e0o\t c\u1ee7a\t h\u1ec7\t th\u1ed1ng\t \u0111\u1ee9ng\t y\u00ean\t m\u00e0\t \u0111i\u1ec3m \u0111\u1ea7u\t v\u00e0\t \u0111i\u1ec3m\t cu\u1ed1i\t c\u1ee7a\t thanh\t c\u1ea7n\t \u0111o\t \u0111\u01b0\u1ee3c\t \u0111\u1ecbnh\t v\u1ecb\t v\u00e0o\t m\u1ed9t\t th\u1eddi \u0111i\u1ec3m\tnh\u1ea5t\t\u0111\u1ecbnh\tt.\tKho\u1ea3ng\tc\u00e1ch\tc\u1ee7a\thai\t\u0111i\u1ec3m\tn\u00e0y,\t\u0111\u01b0\u1ee3c\t\u0111o\tv\u1edbi\tc\u00e2y th\u01b0\u1edbc\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t s\u1eed\t d\u1ee5ng,\t trong\t tr\u01b0\u1eddng\t h\u1ee3p\t n\u00e0y\t l\u00e0\t m\u1ed9t\t th\u01b0\u1edbc\t \u0111o ti\u00eau\tchu\u1ea9n\t\u0111\u1ee9ng\ty\u00ean,\tch\u00ednh\tl\u00e0\tchi\u1ec1u\td\u00e0i\tm\u00e0\tng\u01b0\u1eddi\tta\tc\u00f3\tth\u1ec3\tg\u1ecdi\tl\u00e0 \\\"chi\u1ec1u\td\u00e0i\tc\u1ee7a\tthanh\\\". Theo\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i,\t chi\u1ec1u\t d\u00e0i\t c\u1ea7n\t ph\u1ea3i\t \u0111\u01b0\u1ee3c\t t\u00ecm\t ra trong\tthao\tt\u00e1c\t(a)\t-\tch\u00fang\tta\tmu\u1ed1n\tg\u1ecdi\tn\u00f3\tl\u00e0\t\\\"chi\u1ec1u\td\u00e0i\tc\u1ee7a\tthanh trong\th\u1ec7\tth\u1ed1ng\tchuy\u1ec3n\t\u0111\u1ed9ng\\\"\t-\tl\u00e0\tph\u1ea3i\tb\u1eb1ng\tchi\u1ec1u\td\u00e0i\tl\tc\u1ee7a\tthanh trong\ttr\u1ea1ng\tth\u00e1i\t\u0111\u1ee9ng\ty\u00ean. 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Ch\u00fang\tta\tt\u01b0\u1edfng\tt\u01b0\u1ee3ng\tti\u1ebfp\tr\u1eb1ng\tt\u1ea1i\tm\u1ed7i\t\u0111\u1ed3ng\th\u1ed3\tc\u00f3\tm\u1ed9t\tng\u01b0\u1eddi quan\ts\u00e1t\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u00f9ng\tv\u1edbi\tn\u00f3,\tv\u00e0\tnh\u1eefng\tng\u01b0\u1eddi\tn\u00e0y\t\u00e1p\td\u1ee5ng l\u00ean\thai\t\u0111\u1ed3ng\th\u1ed3\tti\u00eau\tchu\u1ea9n\t\u0111\u01b0\u1ee3c\tthi\u1ebft\tl\u1eadp\ttrong\t\u00a7\t1\tcho\tvi\u1ec7c\t\u0111\u1ed3ng b\u1ed9\th\u00f3a\tc\u1ee7a\thai\t\u0111\u1ed3ng\th\u1ed3.\tV\u00e0o\tth\u1eddi\t\u0111i\u1ec3m[93]\tt\tA\tm\u1ed9t\ttia\ts\u00e1ng\t\u0111i\tt\u1eeb\tA,","n\u00f3\ts\u1ebd\tph\u1ea3n\tchi\u1ebfu\tt\u1ea1i\tB\tv\u00e0o\tth\u1eddi\t\u0111i\u1ec3m\tt\tB\t,\tv\u00e0\ttr\u1edf\tv\u1ec1\tt\u1ea1i\tA\tl\u00fac\tt'\tA\t. 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Thuy\u1ebft\tT\u01b0\u01a1ng\t\u0111\u1ed1i\tL\u00e0\tG\u00ec?\t(1919) B\u00e0i\t n\u00e0y\t \u0111\u01b0\u1ee3c\t Einstein\t vi\u1ebft\t theo\t y\u00eau\t c\u1ea7u\t c\u1ee7a\t b\u00e1o\t The\t London Times\t v\u00e0\t \u0111\u01b0\u1ee3c\t \u0111\u0103ng\t ng\u00e0y\t 28\t th\u00e1ng\t 11\t n\u0103m\t 1919\t v\u1edbi\t nhan\t \u0111\u1ec1 \\\"My\t theory\\\"\t (L\u00fd\t thuy\u1ebft\t c\u1ee7a\t t\u00f4i),\t sau\t khi\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng c\u1ee7a\t Einstein\t \u0111\u01b0\u1ee3c\t c\u00e1c\t \u0111o\u00e0n\t th\u00e1m\t hi\u1ec3m\t Anh\t x\u00e1c\t nh\u1eadn\t v\u00e0\t long tr\u1ecdng\tc\u00f4ng\tb\u1ed1\tv\u00e0o\tng\u00e0y\t6\tth\u00e1ng\t11\tn\u0103m\t1919:\t\u00c1nh\ts\u00e1ng\tc\u1ee7a\tc\u00e1c v\u00ec\t sao\t tr\u00ean\t tr\u1eddi\t b\u1ecb\t cong\t khi\t \u0111i\t qua\t v\u00f9ng\t g\u1ea7n\t m\u1eb7t\t tr\u1eddi\t tr\u01b0\u1edbc\t khi \u0111\u1ebfn\t m\u1eaft\t ch\u00fang\t ta,\t v\u00e0\t \u0111\u1ed9\t cong\t c\u1ee7a\t n\u00f3\t theo\t thuy\u1ebft\t Einstein\t l\u00e0 ch\u00ednh\t x\u00e1c,\t h\u01a1n\t s\u1ef1\t ti\u00ean\t \u0111o\u00e1n\t c\u1ee7a\t thuy\u1ebft\t h\u1ea5p\t d\u1eabn\t Newton.\t B\u00e0i \u0111\u01b0\u1ee3c\t \u0111\u0103ng\t l\u1ea1i\t trong\t Mein\t Weltbild\t (th\u1ebf\t gi\u1edbi\t quan\t c\u1ee7a\t t\u00f4i), Amsterdam,\tNxb.\tQuerido,\t1934. 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Tuy\tnhi\u00ean,\ttr\u1ea1ng\tth\u00e1i\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tkh\u00f4ng\t\u0111\u01b0\u1ee3c ph\u00e9p\t l\u1ef1a\t ch\u1ecdn\t t\u00f9y\t ti\u1ec7n,\t n\u1ebfu\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t c\u1ee7a\t c\u01a1\t h\u1ecdc\t mu\u1ed1n\t c\u00f3 hi\u1ec7u\t l\u1ef1c\t (n\u00f3\t ph\u1ea3i\t \\\"kh\u00f4ng\t quay\\\"\t v\u00e0\t \\\"kh\u00f4ng\t gia\t t\u1ed1c\\\").\t Ng\u01b0\u1eddi\t ta\t g\u1ecdi m\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\t\u0111\u01b0\u1ee3c\tcho\tph\u00e9p\ttrong\tc\u01a1\th\u1ecdc\tl\u00e0\t\\\"h\u1ec7\tqu\u00e1n\tt\u00ednh\\\".\tTuy nhi\u00ean\ttheo\tc\u01a1\th\u1ecdc,\ttr\u1ea1ng\tth\u00e1i\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tm\u1ed9t\th\u1ec7\tquy\tchi\u1ebfu kh\u00f4ng\tph\u1ea3i\t\u0111\u01b0\u1ee3c\tt\u1ef1\tnhi\u00ean\tx\u00e1c\t\u0111\u1ecbnh\tduy\tnh\u1ea5t.\tNg\u01b0\u1ee3c\tl\u1ea1i,\tch\u00fang\tta c\u00f3\t\u0111\u1ecbnh\tl\u00fd\tsau\t\u0111\u00e2y:\tM\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tchuy\u1ec3n\t\u0111\u1ed9ng\tth\u1eb3ng\t\u0111\u1ec1u\t\u0111\u1ed1i\tv\u1edbi m\u1ed9t\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t qu\u00e1n\t t\u00ednh\t c\u0169ng\t l\u00e0\t m\u1ed9t\t h\u1ec7\t qu\u00e1n\t t\u00ednh.\t D\u01b0\u1edbi\t c\u00e1i\t t\u00ean \\\"nguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p\\\"\tng\u01b0\u1eddi\tta\thi\u1ec3u\ts\u1ef1\tkh\u00e1i\tqu\u00e1t\th\u00f3a\t\u0111\u1ecbnh\tl\u00fd n\u00e0y\t \u00e1p\t d\u1ee5ng\t l\u00ean\t c\u00e1c\t hi\u1ec7n\t t\u01b0\u1ee3ng\t t\u1ef1\t nhi\u00ean\t b\u1ea5t\t k\u1ef3;\t ngh\u0129a\t l\u00e0,\t m\u1ed7i hi\u1ec7n\tt\u01b0\u1ee3ng\tt\u1ef1\tnhi\u00ean\tkh\u00e1i\tqu\u00e1t,\tn\u1ebfu\t\u0111\u00fang\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tK, th\u00ec\tc\u0169ng\t\u0111\u00fang\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tK\u2019\tv\u1edbi\tm\u1ed9t\tchuy\u1ec3n\t\u0111\u1ed9ng\tt\u1ecbnh ti\u1ebfn\t\u0111\u1ec1u\t\u0111\u1ed1i\tv\u1edbi\tK. Nguy\u00ean\t l\u00fd\t th\u1ee9\t hai\t m\u00e0\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p\t d\u1ef1a\t v\u00e0o,\t \u0111\u00f3\t l\u00e0 \\\"nguy\u00ean\tl\u00fd\th\u1eb1ng\ts\u1ed1\tv\u1eadn\tt\u1ed1c\t\u00e1nh\ts\u00e1ng\ttrong\tch\u00e2n\tkh\u00f4ng\\\".\tNguy\u00ean l\u00fd\tn\u00e0y\tn\u00f3i:\t\u00c1nh\ts\u00e1ng\tlu\u00f4n\tlu\u00f4n\tc\u00f3\tm\u1ed9t\tv\u1eadn\tt\u1ed1c\ttruy\u1ec1n\tnh\u1ea5t\t\u0111\u1ecbnh, \u0111\u1ed9c\t l\u1eadp\t v\u1edbi\t tr\u1ea1ng\t th\u00e1i\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t ngu\u1ed3n\t ph\u00e1t\t ra\t n\u00f3.\t Ni\u1ec1m tin\tm\u00e0\tc\u00e1c\tnh\u00e0\tv\u1eadt\tl\u00fd\t\u0111\u1eb7t\tv\u00e0o\t\u0111\u1ecbnh\tl\u00fd\tn\u00e0y\tc\u00f3\tngu\u1ed3n\tg\u1ed1c\tt\u1eeb\tnh\u1eefng th\u00e0nh\tc\u00f4ng\tc\u1ee7a\tthuy\u1ebft\t\u0111i\u1ec7n\t\u0111\u1ed9ng\th\u1ecdc\tMaxwell-Lorentz.","C\u1ea3\t hai\t nguy\u00ean\t l\u00fd\t v\u1eeba\t n\u00f3i\t \u0111\u01b0\u1ee3c\t h\u1ed7\t tr\u1ee3\t m\u1ea1nh\t m\u1ebd\t b\u1edfi\t kinh nghi\u1ec7m,\t nh\u01b0ng\t xem\t ra\t l\u1ea1i\t kh\u00f4ng\t dung\t h\u1ee3p\t v\u1edbi\t nhau\t m\u1ed9t\t c\u00e1ch l\u00f4g\u00edc.\t M\u1ed9t\t s\u1ef1\t c\u1ea3i\t bi\u00ean\t \u0111\u1ed9ng\t h\u1ecdc,\t ngh\u0129a\t l\u00e0\t thuy\u1ebft\t v\u1ec1\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt li\u00ean\t quan\t \u0111\u1ebfn\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian\t t\u1eeb\t quan\t \u0111i\u1ec3m\t v\u1eadt\t l\u00fd\t h\u1ecdc, cu\u1ed1i\t c\u00f9ng\t \u0111\u00e3\t cho\t ph\u00e9p\t m\u1ed9t\t s\u1ef1\t k\u1ebft\t h\u1ee3p\t ch\u00fang\t l\u1ea1i\t m\u1ed9t\t c\u00e1ch\t l\u00f4g\u00edc \u0111\u1ec3\t \u0111\u01b0a\t \u0111\u1ebfn\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p.\t N\u00f3\t \u0111\u00e3\t ch\u1ee9ng\t minh\t r\u1eb1ng,\t n\u00f3i \u0111\u1ebfn\tt\u00ednh\t\u0111\u1ed3ng\tth\u1eddi\tc\u1ee7a\thai\ts\u1ef1\tki\u1ec7n\tch\u1ec9\tc\u00f3\t\u00fd\tngh\u0129a\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7 t\u1ecda\t \u0111\u1ed9,\t v\u00e0\t h\u00ecnh\t d\u1ea1ng\t c\u1ee7a\t c\u00e1c\t v\u1eadt\t th\u1ec3\t \u0111o\t l\u01b0\u1eddng\t (th\u01b0\u1edbc\t \u0111o\t ch\u1eb3ng h\u1ea1n)\tc\u0169ng\tnh\u01b0\tt\u1ed1c\t\u0111\u1ed9\tc\u1ee7a\t\u0111\u1ed3ng\th\u1ed3\tph\u1ea3i\tt\u00f9y\tthu\u1ed9c\tv\u00e0o\ttr\u1ea1ng\tth\u00e1i chuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tch\u00fang\t\u0111\u1ed1i\tv\u1edbi\th\u1ec7\tt\u1ecda\t\u0111\u1ed9. Tuy\t nhi\u00ean,\t v\u1eadt\t l\u00fd\t h\u1ecdc\t c\u0169\t bao\t g\u1ed3m\t c\u1ea3\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t chuy\u1ec3n \u0111\u1ed9ng\t Galilei-Newton\t kh\u00f4ng\t c\u00f2n\t ph\u00f9\t h\u1ee3p\t v\u1edbi\t \u0111\u1ed9ng\t h\u1ecdc\t c\u1ee7a thuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tv\u1eeba\t\u0111\u01b0\u1ee3c\t\u0111\u1ec1\tc\u1eadp.\tT\u1eeb\tc\u00e1i\tsau,\tc\u00e1c\t\u0111i\u1ec1u\tki\u1ec7n\tto\u00e1n h\u1ecdc\t ph\u1ed5\t qu\u00e1t\t \u0111\u01b0\u1ee3c\t suy\t ra\t m\u00e0\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1\t nhi\u00ean\t ph\u1ea3i\t tu\u00e2n th\u1ee7,\t n\u1ebfu\t mu\u1ed1n\t hai\t nguy\u00ean\t l\u00fd\t ph\u1ed5\t qu\u00e1t\t n\u00f3i\t tr\u00ean\t th\u1ef1c\t s\u1ef1\t c\u00f3\t hi\u1ec7u l\u1ef1c.\t V\u1eadt\t l\u00fd\t h\u1ecdc\t ph\u1ea3i\t th\u00edch\t \u1ee9ng\t v\u1edbi\t c\u00e1c\t nguy\u00ean\t l\u00fd\t \u0111\u00f3.\t \u0110\u1eb7c\t bi\u1ec7t ng\u01b0\u1eddi\t ta\t \u0111\u1ea1t\t \u0111\u1ebfn\t m\u1ed9t\t \u0111\u1ecbnh\t lu\u1eadt\t chuy\u1ec3n\t \u0111\u1ed9ng\t m\u1edbi\t cho\t c\u00e1c\t \u0111i\u1ec3m kh\u1ed1i\tl\u01b0\u1ee3ng\tchuy\u1ec3n\t\u0111\u1ed9ng\tnhanh,\t\u0111i\u1ec1u\t\u0111\u00e3\t\u0111\u01b0\u1ee3c\tx\u00e1c\tnh\u1eadn\txu\u1ea5t\ts\u1eafc \u1edf\tc\u00e1c\th\u1ea1t\tc\u00f3\tmang\t\u0111i\u1ec7n\tt\u00edch.\tK\u1ebft\tqu\u1ea3\tquan\ttr\u1ecdng\tnh\u1ea5t\tc\u1ee7a\tthuy\u1ebft t\u01b0\u01a1ng\t\u0111\u1ed1i\tl\u00e0\tli\u00ean\tquan\t\u0111\u1ebfn\tkh\u1ed1i\tl\u01b0\u1ee3ng\tqu\u00e1n\tt\u00ednh\tc\u1ee7a\tc\u00e1c\th\u1ec7\tth\u1ed1ng v\u1eadt\t th\u1ec3.\t Ng\u01b0\u1eddi\t ta\t ch\u1ee9ng\t minh\t \u0111\u01b0\u1ee3c\t r\u1eb1ng\t qu\u00e1n\t t\u00ednh\t c\u1ee7a\t m\u1ed9t\t h\u1ec7 th\u1ed1ng\tt\u1ea5t\ty\u1ebfu\tph\u1ea3i\tt\u00f9y\tthu\u1ed9c\tv\u00e0o\th\u00e0m\tl\u01b0\u1ee3ng\tc\u1ee7a\tn\u0103ng\tl\u01b0\u1ee3ng,\tv\u00e0 \u0111i\u1ec1u\tn\u00e0y\td\u1eabn\tt\u1edbi\tquan\t\u0111i\u1ec3m\tr\u1eb1ng\tkh\u1ed1i\tl\u01b0\u1ee3ng\tqu\u00e1n\tt\u00ednh\tkh\u00f4ng\tg\u00ec kh\u00e1c\th\u01a1n\tl\u00e0\tn\u0103ng\tl\u01b0\u1ee3ng\tti\u1ec1m\t\u1ea9n.\t\u0110\u1ecbnh\tl\u00fd\tb\u1ea3o\tt\u1ed3n\tkh\u1ed1i\tl\u01b0\u1ee3ng\tm\u1ea5t \u0111i\t t\u00ednh\t \u0111\u1ed9c\t l\u1eadp\t c\u1ee7a\t n\u00f3\t v\u00e0\t h\u00f2a\t nh\u1eadp\t v\u00e0o\t \u0111\u1ecbnh\t l\u00fd\t b\u1ea3o\t to\u00e0n\t n\u0103ng l\u01b0\u1ee3ng. Thuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p\tl\u00e0\tkh\u00f4ng\tg\u00ec\tkh\u00e1c\th\u01a1n\tm\u1ed9t\ts\u1ef1\tph\u00e1t\ttri\u1ec3n ti\u1ebfp\tt\u1ee5c\tc\u00f3\th\u1ec7\tth\u1ed1ng\tc\u1ee7a\t\u0111i\u1ec7n\t\u0111\u1ed9ng\th\u1ecdc\tMaxwell-Lorentz,\tnh\u01b0ng \u0111\u00e3\t v\u01b0\u1ee3t\t qua\t n\u00f3.\t S\u1ef1\t \u0111\u1ed9c\t l\u1eadp[97]\t c\u1ee7a\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t v\u1eadt\t l\u00fd\t \u0111\u1ed1i\t v\u1edbi tr\u1ea1ng\tth\u00e1i\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tc\u00f3\tph\u1ea3i\tb\u1ecb\tgi\u1edbi\th\u1ea1n\tv\u00e0o\tc\u00e1c lo\u1ea1i\t chuy\u1ec3n\t \u0111\u1ed9ng\t t\u1ecbnh\t ti\u1ebfn\t c\u1ee7a\t c\u00e1c\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t v\u1edbi\t nhau\t hay kh\u00f4ng?\t T\u1ef1\t nhi\u00ean\t l\u00e0m\t g\u00ec\t v\u1edbi\t c\u00e1c\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t c\u1ee7a\t ch\u00fang\t ta\t \u0111\u00e3\t \u0111\u01b0a v\u00e0o,\t v\u00e0\t v\u1edbi\t c\u00e1c\t tr\u1ea1ng\t th\u00e1i\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t ch\u00fang?\t N\u1ebfu\t v\u00ec\t m\u1ee5c \u0111\u00edch\tm\u00f4\tt\u1ea3\tt\u1ef1\tnhi\u00ean\tch\u00fang\tta\tc\u1ea7n\tthi\u1ebft\tph\u1ea3i\ts\u1eed\td\u1ee5ng\tm\u1ed9t\th\u1ec7\tt\u1ecda \u0111\u1ed9\t \u0111\u01b0\u1ee3c\t ch\u1ecdn\t l\u1ef1a\t t\u00f9y\t \u00fd,\t th\u00ec\t s\u1ef1\t ch\u1ecdn\t l\u1ef1a\t tr\u1ea1ng\t th\u00e1i\t chuy\u1ec3n\t \u0111\u1ed9ng c\u1ee7a\tn\u00f3\tkh\u00f4ng\t\u0111\u01b0\u1ee3c\tph\u00e9p\tch\u1ecbu\ts\u1ef1\tgi\u1edbi\th\u1ea1n\tn\u00e0o;\tc\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tph\u1ea3i ho\u00e0n\t to\u00e0n\t \u0111\u1ed9c\t l\u1eadp\t v\u1edbi\t s\u1ef1\t l\u1ef1a\t ch\u1ecdn\t n\u00e0y\t (nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i r\u1ed9ng).","S\u1ef1\tthi\u1ebft\tl\u1eadp\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng\tn\u00e0y\t\u0111\u01b0\u1ee3c\tg\u1ee3i\tra\tb\u1edfi\tm\u1ed9t kinh\t nghi\u1ec7m\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t bi\u1ebft\t t\u1eeb\t l\u00e2u,\t theo\t \u0111\u00f3\t tr\u1ecdng\t l\u01b0\u1ee3ng\t v\u00e0\t qu\u00e1n t\u00ednh\t c\u1ee7a\t m\u1ed9t\t v\u1eadt\t th\u1ec3\t \u0111\u01b0\u1ee3c\t chi\t ph\u1ed1i\t b\u1edfi\t c\u00f9ng\t m\u1ed9t\t h\u1eb1ng\t s\u1ed1\t (\u0111\u1eb3ng th\u1ee9c\tc\u1ee7a\tkh\u1ed1i\tl\u01b0\u1ee3ng\tqu\u00e1n\tt\u00ednh\tv\u00e0\th\u1ea5p\td\u1eabn).\tCh\u1eb3ng\th\u1ea1n\th\u00e3y\tngh\u0129 \u0111\u1ebfn\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tc\u00f3\tchuy\u1ec3n\t\u0111\u1ed9ng\tquay\t\u0111\u1ec1u\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7\tqu\u00e1n t\u00ednh\ttheo\tngh\u0129a\tc\u1ee7a\tNewton.\tC\u00e1c\tl\u1ef1c\tly\tt\u00e2m\txu\u1ea5t\thi\u1ec7n\t\u0111\u1ed1i\tv\u1edbi\th\u1ec7 t\u1ecda\t \u0111\u1ed9\t n\u00e0y\t ph\u1ea3i\t \u0111\u01b0\u1ee3c\t di\u1ec5n\t gi\u1ea3i\t theo\t ngh\u0129a\t c\u1ee7a\t Newton\t nh\u01b0\t l\u00e0 nh\u1eefng\tt\u00e1c\td\u1ee5ng\tc\u1ee7a\tqu\u00e1n\tt\u00ednh.\tNh\u01b0ng\tc\u00e1c\tl\u1ef1c\tly\tt\u00e2m\tn\u00e0y,\ty\tnh\u01b0 c\u00e1c\t l\u1ef1c\t h\u1ea5p\t d\u1eabn,\t l\u00e0\t t\u1ef7\t l\u1ec7\t v\u1edbi\t kh\u1ed1i\t l\u01b0\u1ee3ng\t c\u1ee7a\t v\u1eadt\t th\u1ec3.\t Ch\u00fang\t ta kh\u00f4ng\t\u0111\u01b0\u1ee3c\tph\u00e9p\txem\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tl\u00e0\t\u0111\u1ee9ng\ty\u00ean\tv\u00e0\tc\u00e1c\tl\u1ef1c\tly\tt\u00e2m\tl\u00e0 l\u1ef1c\t c\u1ee7a\t h\u1ea5p\t d\u1eabn\t hay\t sao?\t Quan\t ni\u1ec7m\t \u0111\u00e3\t kh\u00e1\t hi\u1ec3n\t nhi\u00ean,\t nh\u01b0ng c\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n\tc\u1ea5m\tn\u00f3. S\u1ef1\tsuy\tngh\u0129\ttho\u00e1ng\tqua\tn\u00e0y\tl\u00e0m\tch\u00fang\tta\tm\u01b0\u1eddng\tt\u01b0\u1ee3ng\tr\u1eb1ng m\u1ed9t\t l\u00fd\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng\t ph\u1ea3i\t cung\t c\u1ea5p\t \u0111\u01b0\u1ee3c\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt h\u1ea5p\td\u1eabn,\tv\u00e0\ts\u1ef1\ttheo\td\u00f5i\tt\u1edbi\tc\u00f9ng\t\u00fd\tt\u01b0\u1edfng\tn\u00e0y\t\u0111\u00e3\tbi\u1ec7n\tminh\tcho\thy v\u1ecdng\tch\u00fang\tta. Nh\u01b0ng\t con\t \u0111\u01b0\u1eddng\t l\u00e0\t ch\u00f4ng\t gai\t h\u01a1n\t ch\u00fang\t ta\t t\u01b0\u1edfng,\t b\u1edfi\t v\u00ec\t n\u00f3 \u0111\u00f2i\t h\u1ecfi\t s\u1ef1\t t\u1eeb\t b\u1ecf\t h\u00ecnh\t h\u1ecdc\t Euclid.\t \u0110i\u1ec1u\t n\u00e0y\t c\u00f3\t ngh\u0129a:\t C\u00e1c\t \u0111\u1ecbnh lu\u1eadt,\t theo\t \u0111\u00f3\t c\u00e1c\t v\u1eadt\t th\u1ec3\t r\u1eafn\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t s\u1eafp\t x\u1ebfp\t trong\t kh\u00f4ng gian,\t kh\u00f4ng\t ho\u00e0n\t to\u00e0n\t tr\u00f9ng\t kh\u1edbp\t v\u1edbi\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t v\u1ec1\t s\u1eafp\t x\u1ebfp m\u00e0\t h\u00ecnh\t h\u1ecdc\t Euclid\t \u0111\u00e3\t quy\t \u0111\u1ecbnh\t cho\t c\u00e1c\t v\u1eadt\t th\u1ec3.\t \u0110\u00f3\t l\u00e0\t \u0111i\u1ec1u\t ta ngh\u0129\tkhi\tta\tn\u00f3i\t\\\"\u0111\u1ed9\tcong\tc\u1ee7a\tkh\u00f4ng\tgian\\\".\tC\u00e1c\tkh\u00e1i\tni\u1ec7m\tn\u1ec1n\tt\u1ea3ng nh\u01b0\t \\\"\u0111\u01b0\u1eddng\t th\u1eb3ng\\\",\t \\\"m\u1eb7t\t ph\u1eb3ng\\\",\t v.v.\t qua\t \u0111\u00f3\t m\u1ea5t\t \u0111i\t \u00fd\t ngh\u0129a ch\u00ednh\tx\u00e1c\tc\u1ee7a\tn\u00f3\ttrong\tv\u1eadt\tl\u00fd. Trong\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng,\t h\u1ecdc\t thuy\u1ebft\t v\u1ec1\t kh\u00f4ng\t gian\t v\u00e0 th\u1eddi\t gian,\t hay\t \u0111\u1ed9ng\t h\u1ecdc,\t kh\u00f4ng\t c\u00f2n\t \u0111\u00f3ng\t vai\t tr\u00f2\t c\u1ee7a\t m\u1ed9t\t n\u1ec1n t\u1ea3ng\t \u0111\u1ed9c\t l\u1eadp\t n\u1eefa\t \u0111\u1ed1i\t v\u1edbi\t ph\u1ea7n\t v\u1eadt\t l\u00fd\t c\u00f2n\t l\u1ea1i.\t S\u1ef1\t v\u1eadn\t h\u00e0nh\t h\u00ecnh h\u1ecdc\tc\u1ee7a\tc\u00e1c\tv\u1eadt\tth\u1ec3,\tv\u00e0\tt\u1ed1c\t\u0111\u1ed9\tc\u1ee7a\tc\u00e1c\t\u0111\u1ed3ng\th\u1ed3\t\u0111\u00fang\th\u01a1n\tl\u1ec7\tthu\u1ed9c v\u00e0o\t c\u00e1c\t tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn,\t nh\u1eefng\t c\u00e1i\t \u0111\u01b0\u1ee3c\t sinh\t ra\t b\u1edfi\t ch\u00ednh\t v\u1eadt ch\u1ea5t. L\u00fd\t thuy\u1ebft\t m\u1edbi\t c\u1ee7a\t h\u1ea5p\t d\u1eabn,\t x\u00e9t\t v\u1ec1\t m\u1eb7t\t nguy\u00ean\t l\u00fd,\t kh\u00e1c\t bi\u1ec7t \u0111\u00e1ng\t k\u1ec3\t v\u1edbi\t l\u00fd\t thuy\u1ebft\t Newton.\t Nh\u01b0ng\t c\u00e1c\t k\u1ebft\t qu\u1ea3\t th\u1ef1c\t nghi\u1ec7m c\u1ee7a\t n\u00f3\t tr\u00f9ng\t h\u1ee3p\t r\u1ea5t\t g\u1ea7n\t v\u1edbi\t c\u00e1c\t k\u1ebft\t qu\u1ea3\t th\u1ef1c\t nghi\u1ec7m\t c\u1ee7a Newton\t\u0111\u1ebfn\tn\u1ed7i\tkh\u00f3\tt\u00ecm\tra\t\u0111\u01b0\u1ee3c\tnh\u1eefng\tti\u00eau\tchu\u1ea9n\tph\u00e2n\tbi\u1ec7t\tc\u00f3 th\u1ec3\tki\u1ec3m\tch\u1ee9ng\tb\u1eb1ng\tth\u1ef1c\tnghi\u1ec7m.\tNh\u1eefng\tti\u00eau\tchu\u1ea9n\tph\u00e2n\tbi\u1ec7t nh\u01b0\tth\u1ebf\t\u0111\u01b0\u1ee3c\tt\u00ecm\tth\u1ea5y\t\u0111\u1ebfn\tnay\tl\u00e0:","1.\tTrong\tchuy\u1ec3n\t\u0111\u1ed9ng\tquay\tc\u1ee7a\tc\u00e1c\tellip\tc\u1ee7a\tqu\u1ef9\t\u0111\u1ea1o\tc\u00e1c\th\u00e0nh tinh\tquanh\tm\u1eb7t\ttr\u1eddi\t(\u0111\u01b0\u1ee3c\tx\u00e1c\tnh\u1eadn\t\u1edf\tSao\tTh\u1ee7y) 2.\tTrong\ts\u1ef1\tu\u1ed1n\tcong\tc\u1ee7a\tc\u00e1c\ttia\ts\u00e1ng\t\u0111i\tngang\tqua\tc\u00e1c\ttr\u01b0\u1eddng h\u1ea5p\td\u1eabn\t(\u0111\u01b0\u1ee3c\t x\u00e1c\t nh\u1eadn\t b\u1edfi\t c\u00e1c\t \u1ea3nh\t ch\u1ee5p\t c\u1ee7a\t c\u00e1c\t nh\u00e0\t th\u00e1m\t hi\u1ec3m Anh\ttrong\td\u1ecbp\tnh\u1eadt\tth\u1ef1c\tto\u00e0n\tph\u1ea7n) 3.\tTrong\tm\u1ed9t\ts\u1ef1\tchuy\u1ec3n\td\u1ecbch\tc\u1ee7a\tc\u00e1c\tv\u1ea1ch\tquang\tph\u1ed5\tv\u1ec1\tph\u00eda \u0111\u00f3\t c\u1ee7a\t \u00e1nh\t s\u00e1ng\t \u0111\u1ebfn\t ch\u00fang\t ta\t \u0111\u01b0\u1ee3c\t ph\u00e1t\t ra\t t\u1eeb\t c\u00e1c\t sao\t c\u00f3\t kh\u1ed1i l\u01b0\u1ee3ng\t\u0111\u00e1ng\tk\u1ec3\t(sau\tn\u00e0y\tc\u0169ng\t\u0111\u01b0\u1ee3c\tx\u00e1c\tnh\u1eadn\tlu\u00f4n). S\u1ef1\th\u1ea5p\td\u1eabn\tch\u00ednh\tc\u1ee7a\tl\u00fd\tthuy\u1ebft\tn\u1eb1m\t\u1edf\tt\u00ednh\tkh\u00e9p\tk\u00edn\tl\u00f4g\u00edc\tc\u1ee7a n\u00f3.\t N\u1ebfu\t m\u1ed9t\t h\u1ec7\t qu\u1ea3\t duy\t nh\u1ea5t\t suy\t ra\t t\u1eeb\t n\u00f3\t b\u1ecb\t x\u00e1c\t nh\u1eadn\t l\u00e0\t kh\u00f4ng \u0111\u00fang,\tth\u00ec\tl\u00fd\tthuy\u1ebft\tph\u1ea3i\tb\u1ecb\tt\u1eeb\tb\u1ecf;\tm\u1ed9t\ts\u1ef1\tc\u1ea3i\tbi\u00ean\tc\u00f3\tl\u1ebd\tkh\u00f4ng\tth\u1ec3 th\u1ef1c\thi\u1ec7n\t\u0111\u01b0\u1ee3c\tm\u00e0\tkh\u00f4ng\tph\u1ea3i\tph\u00e1\th\u1ee7y\tc\u1ea3\tt\u00f2a\tnh\u00e0. Tuy\t nhi\u00ean\t kh\u00f4ng\t n\u00ean\t ngh\u0129\t r\u1eb1ng,\t b\u1eb1ng\t l\u00fd\t thuy\u1ebft\t n\u00e0y\t hay\t m\u1ed9t l\u00fd\tthuy\u1ebft\tb\u1ea5t\tk\u1ef3\tn\u00e0o\tkh\u00e1c\tm\u00e0\tc\u00f4ng\ttr\u00ecnh\tv\u0129\t\u0111\u1ea1i\tc\u1ee7a\tNewton\tc\u00f3\tth\u1ec3 b\u1ecb\t thay\t th\u1ebf\t theo\t \u0111\u00fang\t ngh\u0129a\t c\u1ee7a\t n\u00f3.\t C\u00e1c\t \u00fd\t t\u01b0\u1edfng\t s\u00e1ng\t s\u1ee7a\t v\u00e0\t v\u0129 \u0111\u1ea1i\t c\u1ee7a\t \u00f4ng\t s\u1ebd\t v\u1eabn\t gi\u1eef\t nguy\u00ean\t \u00fd\t ngh\u0129a\t tuy\u1ec7t\t di\u1ec7u\t c\u1ee7a\t ch\u00fang trong\t m\u1ecdi\t th\u1eddi\t \u0111\u1ea1i\t t\u01b0\u01a1ng\t lai\t l\u00e0\t nh\u01b0\t n\u1ec1n\t t\u1ea3ng\t c\u1ee7a\t s\u1ef1\t h\u00ecnh\t th\u00e0nh kh\u00e1i\t ni\u1ec7m\t hi\u1ec7n\t \u0111\u1ea1i\t c\u1ee7a\t ch\u00fang\t ta\t trong\t l\u00e3nh\t v\u1ef1c\t tri\u1ebft\t h\u1ecdc\t t\u1ef1 nhi\u00ean. [\tPh\u1ee5\tch\u00fa:\t M\u1ed9t\t s\u1ed1\t \u0111i\u1ec1u\t c\u1ee7a\t Qu\u00fd\t B\u00e1o\t li\u00ean\t quan\t \u0111\u1ebfn\t c\u00e1\t nh\u00e2n\t v\u00e0 cu\u1ed9c\t \u0111\u1eddi\t t\u00f4i\t c\u00f3\t ngu\u1ed3n\t g\u1ed1c\t t\u1eeb\t \u00f3c\t t\u01b0\u01a1ng\t t\u01b0\u1ee3ng\t s\u00f4i\t n\u1ed5i\t c\u1ee7a\t t\u00e1c\t gi\u1ea3. \u0110\u00e2y,\t c\u00f2n\t m\u1ed9t\t lo\u1ea1i\t \u1ee9ng\t d\u1ee5ng\t kh\u00e1c\t c\u1ee7a\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t \u0111\u1ec3 gi\u00fap\t vui\t cho\t b\u1ea1n\t \u0111\u1ecdc:\t H\u00f4m\t nay\t \u1edf\t \u0110\u1ee9c\t t\u00f4i\t \u0111\u01b0\u1ee3c\t g\u1ecdi\t l\u00e0\t m\u1ed9t\t \\\"nh\u00e0 th\u00f4ng\t th\u00e1i\t \u0110\u1ee9c\\\"\t v\u00e0\t \u1edf\t Anh\t l\u00e0\t m\u1ed9t\t \\\"ng\u01b0\u1eddi\t Do\t Th\u00e1i\t Th\u1ee5y\t S\u1ef9\\\".\t N\u1ebfu l\u00fac\t n\u00e0o\t \u0111\u00f3\t \u0111\u1ecbnh\t m\u1ec7nh\t b\u1eaft\t t\u00f4i\t b\u1ecb\t xem\t nh\u01b0\t \\\"con\t v\u1eadt\t gh\u00ea\t t\u1edfm\\\",\t th\u00ec ng\u01b0\u1ee3c\tl\u1ea1i\tt\u00f4i\t\u0111\u1ed1i\tv\u1edbi\tng\u01b0\u01a1i\t\u0110\u1ee9c\tl\u00e0\tm\u1ed9t\t\\\"ng\u01b0\u1eddi\tDo\tTh\u00e1i\tTh\u1ee5y\tS\u1ef9\\\"\tv\u00e0 \u0111\u1ed1i\tv\u1edbi\tng\u01b0\u1eddi\tAnh\tl\u00e0\tm\u1ed9t\t\\\"nh\u00e0\tth\u00f4ng\tth\u00e1i\t\u0110\u1ee9c\\\".] V\u1ec1\tThuy\u1ebft\tT\u01b0\u01a1ng\t\u0110\u1ed1i\t(1921) B\u00e0i\t di\u1ec5n\t v\u0103n\t t\u1ea1i\t King's\t College,\t London,\t n\u0103m\t 1921,\t c\u00f2n\t \u0111\u01b0\u1ee3c g\u1ecdi\t l\u00e0\t \\\"B\u00e0i\t di\u1ec5n\t v\u0103n\t Lu\u00e2n\t \u0110\u00f4n\\\",\t \u0111\u01b0\u1ee3c\t \u0111\u0103ng\t l\u1ea1i\t trong\t Mein Weltbild,\tAmsterdam,\tNxb.\tQuerido,\t1934. Th\u1eadt\t l\u00e0\t m\u1ed9t\t ni\u1ec1m\t vui\t \u0111\u1eb7c\t bi\u1ec7t\t cho\t t\u00f4i\t v\u00e0o\t h\u00f4m\t nay\t \u0111\u01b0\u1ee3c\t n\u00f3i chuy\u1ec7n\t t\u1ea1i\t th\u1ee7\t \u0111\u00f4\t c\u1ee7a\t \u0111\u1ea5t\t n\u01b0\u1edbc\t m\u00e0\t t\u1eeb\t \u0111\u00e2y\t nh\u1eefng\t \u00fd\t t\u01b0\u1edfng\t n\u1ec1n t\u1ea3ng\t quan\t tr\u1ecdng\t nh\u1ea5t\t c\u1ee7a\t ng\u00e0nh\t v\u1eadt\t l\u00fd\t l\u00fd\t thuy\u1ebft\t \u0111\u00e3\t \u0111i\t v\u00e0o\t th\u1ebf","gi\u1edbi.\t T\u00f4i\t ngh\u0129\t \u0111\u1ebfn\t l\u00fd\t thuy\u1ebft\t v\u1ec1\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t c\u00e1c\t kh\u1ed1i\t l\u01b0\u1ee3ng v\u00e0\t \u0111\u1ebfn\t h\u1ea5p\t d\u1eabn\t m\u00e0\t Newton\t \u0111\u00e3\t t\u1eb7ng\t ch\u00fang\t ta,\t v\u00e0\t \u0111\u1ebfn\t kh\u00e1i\t ni\u1ec7m tr\u01b0\u1eddng\t\u0111i\u1ec7n\tt\u1eeb,\tqua\t\u0111\u00f3\tFaraday\tv\u00e0\tMaxwell\t\u0111\u00e3\t\u0111em\tl\u1ea1i\tcho\tng\u00e0nh v\u1eadt\t l\u00fd\t m\u1ed9t\t c\u01a1\t s\u1edf\t m\u1edbi.\t Ng\u01b0\u1eddi\t ta\t c\u00f3\t th\u1ec3\t n\u00f3i,\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t \u0111\u00e3 mang\t l\u1ea1i\t m\u1ed9t\t c\u00e1ch\t k\u1ebft\t th\u00fac\t cho\t t\u00f2a\t nh\u00e0\t \u00fd\t t\u01b0\u1edfng\t tuy\u1ec7t\t v\u1eddi\t c\u1ee7a Maxwell\t v\u00e0\t Lorentz,\t b\u1eb1ng\t c\u00e1ch\t n\u00f3\t n\u1ed7\t l\u1ef1c\t m\u1edf\t r\u1ed9ng\t v\u1eadt\t l\u00fd\t tr\u01b0\u1eddng \u0111\u1ebfn\tt\u1ea5t\tc\u1ea3\tc\u00e1c\thi\u1ec7n\tt\u01b0\u1ee3ng,\tk\u1ebf\tc\u1ea3\thi\u1ec7n\tt\u01b0\u1ee3ng\th\u1ea5p\td\u1eabn. Tr\u1edf\t l\u1ea1i\t \u0111\u1ec1\t t\u00e0i\t ch\u00ednh\t l\u00e0\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i,\t t\u00f4i\t mu\u1ed1n\t n\u00eau\t b\u1eadt\t l\u00ean r\u1eb1ng,\tl\u00fd\tthuy\u1ebft\tn\u00e0y\tkh\u00f4ng\tc\u00f3\tngu\u1ed3n\tg\u1ed1c\tt\u01b0\tbi\u1ec7n;\ts\u1ef1\tkh\u00e1m\tph\u00e1\tn\u00f3 ho\u00e0n\t to\u00e0n\t d\u1ef1a\t v\u00e0o\t n\u1ed7\t l\u1ef1c\t th\u00edch\t nghi\t l\u00fd\t thuy\u1ebft\t v\u1eadt\t l\u00fd\t v\u00e0o\t c\u00e1c\t d\u1eef ki\u1ec7n\t quan\t s\u00e1t\t \u0111\u01b0\u1ee3c,\t c\u00e0ng\t nhi\u1ec1u\t nh\u01b0\t c\u00f3\t th\u1ec3.\t \u1ede\t \u0111\u00e2y\t kh\u00f4ng\t h\u1ec1\t c\u00f3 m\u1ed9t\t h\u00e0nh\t \u0111\u1ed9ng\t c\u00e1ch\t m\u1ea1ng,\t m\u00e0\t l\u00e0\t m\u1ed9t\t s\u1ef1\t ph\u00e1t\t tri\u1ec3n\t ti\u1ebfp\t t\u1ee5c\t t\u1ef1 nhi\u00ean\tc\u1ee7a\tm\u1ed9t\tcon\t\u0111\u01b0\u1eddng\t\u0111\u00e3\t\u0111\u01b0\u1ee3c\ttheo\t\u0111u\u1ed5i\tt\u1eeb\tnhi\u1ec1u\tth\u1ebf\tk\u1ef7.\tS\u1ef1 t\u1eeb\t b\u1ecf\t m\u1ed9t\t s\u1ed1\t kh\u00e1i\t ni\u1ec7m\t nh\u1ea5t\t \u0111\u1ecbnh\t \u0111\u01b0\u1ee3c\t xem\t l\u00e0\t c\u0103n\t b\u1ea3n\t \u0111\u1ebfn\t nay v\u1ec1\t kh\u00f4ng\t gian,\t th\u1eddi\t gian\t v\u00e0\t chuy\u1ec3n\t \u0111\u1ed9ng,\t kh\u00f4ng\t n\u00ean\t \u0111\u01b0\u1ee3c\t quan ni\u1ec7m\tnh\u01b0\tm\u1ed9t\tvi\u1ec7c\tl\u00e0m\tt\u00f9y\tti\u1ec7n,\tm\u00e0\tch\u1ec9\tv\u00ec\tb\u1ecb\tchi\tph\u1ed1i\tb\u1edfi\tc\u00e1c\td\u1eef ki\u1ec7n\t\u0111\u01b0\u1ee3c\tquan\ts\u00e1t. \u0110\u1ecbnh\tlu\u1eadt\th\u1eb1ng\ts\u1ed1\tc\u1ee7a\tv\u1eadn\tt\u1ed1c\ttruy\u1ec1n\tc\u1ee7a\t\u00e1nh\ts\u00e1ng\ttrong\tch\u00e2n kh\u00f4ng,\t\u0111i\u1ec1u\t\u0111\u01b0\u1ee3c\tc\u1ee7ng\tc\u1ed1\tb\u1edfi\ts\u1ef1\tph\u00e1t\ttri\u1ec3n\tc\u1ee7a\t\u0111i\u1ec7n\t\u0111\u1ed9ng\th\u1ecdc\tv\u00e0 quang\th\u1ecdc;\ts\u1ef1\tb\u00ecnh\t\u0111\u1eb3ng\tch\u00ednh\t\u0111\u00e1ng\tc\u1ee7a\tt\u1ea5t\tc\u1ea3\tc\u00e1c\th\u1ec7\tqu\u00e1n\tt\u00ednh (nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p),\t \u0111i\u1ec1u\t \u0111\u01b0\u1ee3c\t di\u1ec5n\t t\u1ea3\t s\u1eafc\t n\u00e9t\t \u0111\u1eb7c\t bi\u1ec7t trong\t th\u00ed\t nghi\u1ec7m\t n\u1ed1i\t ti\u1ebfng\t c\u1ee7a\t Michelson;\t c\u1ea3\t hai\t tr\u01b0\u1edbc\t ti\u00ean\t \u0111\u01b0a \u0111\u1ebfn\t k\u1ebft\t qu\u1ea3\t r\u1eb1ng\t kh\u00e1i\t ni\u1ec7m\t th\u1eddi\t gian\t c\u1ea7n\t ph\u1ea3i\t \u0111\u01b0\u1ee3c\t t\u01b0\u01a1ng\t \u0111\u1ed1i h\u00f3a,\tb\u1eb1ng\tc\u00e1ch\tph\u1ea3i\tcho\tm\u1ed7i\th\u1ec7\tqu\u00e1n\tt\u00ednh\tth\u1eddi\tgian\t\u0111\u1eb7c\tbi\u1ec7t\tc\u1ee7a n\u00f3.\t Trong\t khi\t ph\u00e1t\t tri\u1ec3n\t \u00fd\t t\u01b0\u1edfng\t n\u00e0y,\t ng\u01b0\u1eddi\t ta\t th\u1ea5y\t r\u1eb1ng\t tr\u01b0\u1edbc \u0111\u00e2y\tm\u1ed1i\tt\u01b0\u01a1ng\tquan\tgi\u1eefa\tc\u00e1c\ttr\u1ea3i\tnghi\u1ec7m\ttr\u1ef1c\tti\u1ebfp\tm\u1ed9t\tm\u1eb7t,\tc\u00e1c t\u1ecda\t\u0111\u1ed9\tv\u00e0\tth\u1eddi\tgian\tm\u1eb7t\tkia,\tch\u01b0a\t\u0111\u01b0\u1ee3c\tsuy\tngh\u0129\ts\u00e2u\ts\u1eafc\t\u0111\u1ea7y\t\u0111\u1ee7. N\u00f3i\t chung,\t m\u1ed9t\t trong\t nh\u1eefng\t n\u00e9t\t ch\u00ednh\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i l\u00e0\t n\u00f3\t n\u1ed7\t l\u1ef1c\t l\u00e0m\t r\u00f5\t ra\t c\u00e1c\t m\u1ed1i\t quan\t h\u1ec7\t c\u1ee7a\t c\u00e1c\t kh\u00e1i\t ni\u1ec7m\t kh\u00e1i qu\u00e1t\t v\u1edbi\t nh\u1eefng\t d\u1eef\t ki\u1ec7n\t \u0111\u01b0\u1ee3c\t tr\u1ea3i\t nghi\u1ec7m\t m\u1ed9t\t c\u00e1ch\t ch\u00ednh\t x\u00e1c h\u01a1n.\t Nguy\u00ean\t t\u1eafc\t c\u01a1\t b\u1ea3n\t \u1edf\t \u0111\u00e2y\t lu\u00f4n\t lu\u00f4n\t l\u00e0,\t s\u1ef1\t ch\u00ednh\t \u0111\u00e1ng\t c\u1ee7a m\u1ed9t\tkh\u00e1i\tni\u1ec7m\tv\u1eadt\tl\u00fd\tn\u1eb1m\tho\u00e0n\tto\u00e0n\ttrong\tm\u1ed1i\tquan\th\u1ec7\ts\u00e1ng\ts\u1ee7a v\u00e0\t minh\t b\u1ea1ch\t c\u1ee7a\t n\u00f3\t v\u1edbi\t c\u00e1c\t d\u1eef\t ki\u1ec7n\t tr\u1ea3i\t nghi\u1ec7m\t \u0111\u01b0\u1ee3c.\t Theo thuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p,\tc\u00e1c\tt\u1ecda\t\u0111\u1ed9\tkh\u00f4ng\tgian\tv\u00e0\tth\u1eddi\tgian\tv\u1eabn\tc\u00f2n gi\u1eef\tt\u00ednh\tch\u1ea5t\ttuy\u1ec7t\t\u0111\u1ed1i\ttrong\tch\u1eebng\tm\u1ef1c\tch\u00fang\t\u0111\u01b0\u1ee3c\t\u0111o\ttr\u1ef1c\tti\u1ebfp b\u1edfi\tc\u00e1c\t\u0111\u1ed3ng\th\u1ed3\tv\u00e0\tv\u1eadt\tth\u1ec3\tr\u1eafn.\tNh\u01b0ng\tch\u00fang\tc\u00f3\tt\u00ednh\tch\u1ea5t\tt\u01b0\u01a1ng \u0111\u1ed1i\ttrong\tch\u1eebng\tm\u1ef1c\tch\u00fang\tl\u1ec7\tthu\u1ed9c\tv\u00e0o\ttr\u1ea1ng\tth\u00e1i\tchuy\u1ec3n\t\u0111\u1ed9ng","c\u1ee7a\t h\u1ec7\t qu\u00e1n\t t\u00ednh\t \u0111\u01b0\u1ee3c\t ch\u1ecdn.\t Continum\t b\u1ed1n\t chi\u1ec1u,\t \u0111\u01b0\u1ee3c\t t\u1ea1o\t n\u00ean b\u1edfi\t s\u1ef1\t h\u1ee3p\t nh\u1ea5t\t c\u1ee7a\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian,\t v\u1eabn\t gi\u1eef\t t\u00ednh\t ch\u1ea5t tuy\u1ec7t\t \u0111\u1ed1i\t theo\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p,\t c\u0169ng\t l\u00e0\t t\u00ednh\t ch\u1ea5t\t m\u00e0\t theo thuy\u1ebft\t c\u1ee7a\t kh\u00f4ng\t gian\t l\u1eabn\t th\u1eddi\t gian\t s\u1edf\t h\u1eefu\t ri\u00eang\t bi\u1ec7t\t nhau.\t T\u1eeb s\u1ef1\t di\u1ec5n\t gi\u1ea3i\t t\u1ecda\t \u0111\u1ed9\t v\u00e0\t th\u1eddi\t gian\t nh\u01b0\t l\u00e0\t nh\u1eefng\t k\u1ebft\t qu\u1ea3\t c\u1ee7a\t s\u1ef1\t \u0111o \u0111\u1ea1c,\t ng\u01b0\u1eddi\t ta\t suy\t ra\t \u1ea3nh\t h\u01b0\u1edfng\t c\u1ee7a\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u01b0\u01a1ng\t \u0111\u1ed1i\t \u0111\u1ed1i v\u1edbi\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t l\u00ean\t h\u00ecnh\t d\u1ea1ng\t c\u1ee7a\t c\u00e1c\t v\u1eadt\t th\u1ec3\t v\u00e0\t l\u00ean\t v\u1eadn\t t\u1ed1c\t c\u1ee7a \u0111\u1ed3ng\t h\u1ed3,\t c\u0169ng\t nh\u01b0\t suy\t ra\t s\u1ef1\t t\u01b0\u01a1ng\t \u0111\u01b0\u01a1ng\t c\u1ee7a\t n\u0103ng\t l\u01b0\u1ee3ng\t v\u00e0 kh\u1ed1i\tl\u01b0\u1ee3ng\tqu\u00e1n\tt\u00ednh. Ngu\u1ed3n\tg\u1ed1c\tc\u1ee7a\ts\u1ef1\th\u00ecnh\tth\u00e0nh\tc\u1ee7a\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng\ttr\u01b0\u1edbc h\u1ebft\tb\u1eaft\tngu\u1ed3n\tt\u1eeb\td\u1eef\tki\u1ec7n\tth\u1ef1c\tnghi\u1ec7m\tc\u1ee7a\t\u0111\u1eb3ng\tth\u1ee9c\th\u1eb1ng\ts\u1ed1\tc\u1ee7a kh\u1ed1i\tl\u01b0\u1ee3ng\tqu\u00e1n\tt\u00ednh\tv\u00e0\tkh\u1ed1i\tl\u01b0\u1ee3ng\th\u1ea5p\td\u1eabn\tc\u1ee7a\tc\u00e1c\tv\u1eadt\tth\u1ec3,\tm\u00e0 v\u1eadt\tl\u00fd\tc\u1ed5\t\u0111i\u1ec3n\t\u0111\u00e3\tkh\u00f4ng\tcung\tc\u1ea5p\t\u0111\u01b0\u1ee3c\ts\u1ef1\tl\u00fd\tgi\u1ea3i\tn\u00e0o\tcho\ts\u1ef1\tth\u1eadt c\u0103n\t b\u1ea3n\t \u0111\u00f3.\t Ng\u01b0\u1eddi\t ta\t \u0111\u1ea1t\t \u0111\u1ebfn\t m\u1ed9t\t s\u1ef1\t l\u00fd\t gi\u1ea3i\t nh\u01b0\t th\u1ebf\t b\u1eb1ng\t s\u1ef1\t m\u1edf r\u1ed9ng\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\t\u0111\u1ebfn\tc\u00e1c\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tchuy\u1ec3n\t\u0111\u1ed9ng\tgia\tt\u1ed1c t\u01b0\u01a1ng\t \u0111\u1ed1i\t v\u1edbi\t nhau.\t Vi\u1ec7c\t \u0111\u01b0a\t v\u00e0o\t c\u00e1c\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t c\u00f3\t chuy\u1ec3n\t \u0111\u1ed9ng gia\t t\u1ed1c\t \u0111\u1ed1i\t v\u1edbi\t c\u00e1c\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t qu\u00e1n\t t\u00ednh\t \u0111\u00e3\t l\u00e0m\t xu\u1ea5t\t hi\u1ec7n\t c\u00e1c tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn\t \u0111\u1ed1i\t v\u1edbi\t c\u00e1c\t h\u1ec7\t qu\u00e1n\t t\u00ednh.\t Nh\u01b0\t m\u1ed9t\t h\u1ec7\t lu\u1eadn\t c\u1ee7a \u0111i\u1ec1u\t n\u00e0y,\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng,\t v\u1ed1n\t \u0111\u01b0\u1ee3c\t x\u00e2y\t d\u1ef1ng\t tr\u00ean\t \u0111\u1eb3ng th\u1ee9c\t c\u1ee7a\t qu\u00e1n\t t\u00ednh\t v\u00e0\t tr\u1ecdng\t l\u1ef1c,\t cung\t c\u1ea5p\t m\u1ed9t\t l\u00fd\t thuy\u1ebft\t c\u1ee7a tr\u01b0\u1eddng\th\u1ea5p\td\u1eabn. Vi\u1ec7c\t\u0111\u01b0a\tv\u00e0o\tc\u00e1c\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tchuy\u1ec3n\t\u0111\u1ed9ng\tgia\tt\u1ed1c\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tnhau nh\u01b0\tnh\u1eefng\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tb\u00ecnh\t\u0111\u1eb3ng,\tnh\u01b0\tch\u00fang\t\u0111\u00e3\th\u00ecnh\tth\u00e0nh\td\u01b0\u1edbi s\u1ef1\t chi\t ph\u1ed1i\t c\u1ee7a\t \u0111\u1eb3ng\t th\u1ee9c\t gi\u1eefa\t qu\u00e1n\t t\u00ednh\t v\u00e0\t tr\u1ecdng\t l\u1ef1c,\t c\u00f9ng\t v\u1edbi nh\u1eefng\t k\u1ebft\t qu\u1ea3\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p\t \u0111\u00e3\t d\u1eabn\t \u0111\u1ebfn\t h\u1ec7\t lu\u1eadn r\u1eb1ng,\t \u0111\u1ecbnh\t lu\u1eadt\t chi\t ph\u1ed1i\t s\u1ef1\t s\u1eafp\t x\u1ebfp\t c\u00e1c\t v\u1eadt\t th\u1ec3\t r\u1eafn\t kh\u00f4ng\t tu\u00e2n theo\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t c\u1ee7a\t h\u00ecnh\t h\u1ecdc\t Euclid\t khi\t c\u00f3\t s\u1ef1\t hi\u1ec7n\t di\u1ec7n\t c\u1ee7a tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn.\t Ch\u00fang\t ta\t c\u00f3\t m\u1ed9t\t k\u1ebft\t qu\u1ea3\t t\u01b0\u01a1ng\t t\u1ef1\t cho\t v\u1eadn\t t\u1ed1c c\u1ee7a\t \u0111\u1ed3ng\t h\u1ed3.\t \u0110i\u1ec1u\t n\u00e0y\t \u0111\u01b0a\t \u0111\u1ebfn\t s\u1ef1\t c\u1ea7n\t thi\u1ebft\t kh\u00e1i\t qu\u00e1t\t h\u00f3a\t m\u1ed9t l\u1ea7n\t n\u1eefa\t l\u00fd\t thuy\u1ebft\t v\u1ec1\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian,\t b\u1edfi\t v\u00ec\t gi\u1edd\t \u0111\u00e2y\t s\u1ef1 di\u1ec5n\t gi\u1ea3i\t tr\u1ef1c\t ti\u1ebfp\t c\u1ee7a\t c\u00e1c\t t\u1ecda\t \u0111\u1ed9\t kh\u00f4ng\t gian\t v\u00e0\t th\u1eddi\t gian\t b\u1eb1ng c\u00e1c\t \u0111o\t \u0111\u1ea1c\t thu\t ho\u1ea1ch\t \u0111\u01b0\u1ee3c\t v\u1edbi\t th\u01b0\u1edbc\t \u0111o\t v\u00e0\t \u0111\u1ed3ng\t h\u1ed3\t kh\u00f4ng\t c\u00f2n \u0111\u00fang\tn\u1eefa.\tC\u00e1i\tkh\u00e1i\tqu\u00e1t\th\u00f3a\tc\u1ee7a\tmetric,\tv\u1ed1n\t\u0111\u00e3\tt\u1ed3n\tt\u1ea1i\ttr\u00ean\tl\u00e3nh v\u1ef1c\t to\u00e1n\t h\u1ecdc\t thu\u1ea7n\t t\u00fay\t b\u1eb1ng\t nh\u1eefng\t nghi\u00ean\t c\u1ee9u\t c\u1ee7a\t Gauss\t v\u00e0 Riemann,\t c\u01a1\t b\u1ea3n\t d\u1ef1a\t tr\u00ean\t s\u1ef1\t th\u1eadt\t metric\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i h\u1eb9p\t c\u0169ng\t c\u00f2n\t c\u00f3\t th\u1ec3\t y\u00eau\t s\u00e1ch\t hi\u1ec7u\t l\u1ef1c\t cho\t c\u00e1c\t mi\u1ec1n\t nh\u1ecf\t trong tr\u01b0\u1eddng\th\u1ee3p\tt\u1ed5ng\tqu\u00e1t.","Qu\u00e1\ttr\u00ecnh\tph\u00e1t\ttri\u1ec3n\t\u0111\u01b0\u1ee3c\tm\u00f4\tt\u1ea3\t\u1edf\t\u0111\u00e2y\tl\u1ea5y\tm\u1ea5t\t\u0111i\tm\u1ecdi\tth\u1ef1c\tt\u1ea1i \u0111\u1ed9c\tl\u1eadp\tc\u1ee7a\tc\u00e1c\tt\u1ecda\t\u0111\u1ed9\tkh\u00f4ng-th\u1eddi-gian.\tC\u00e1i\tth\u1ef1c\tt\u1ea1i\tc\u00f3\tt\u00ednh\tch\u1ea5t metric\t ch\u1ec9\t b\u00e2y\t gi\u1edd\t m\u1edbi\t \u0111\u01b0\u1ee3c\t x\u00e1c\t \u0111\u1ecbnh\t b\u1edfi\t s\u1ef1\t k\u1ebft\t h\u1ee3p\t c\u1ee7a\t c\u00e1c\t t\u1ecda \u0111\u1ed9\tkh\u00f4ng-th\u1eddi-gian\tv\u1edbi\tc\u00e1c\t\u0111\u1ea1i\tl\u01b0\u1ee3ng\tto\u00e1n\th\u1ecdc\tm\u00f4\tt\u1ea3\ttr\u01b0\u1eddng\th\u1ea5p d\u1eabn. C\u00f3\t m\u1ed9t\t g\u1ed1c\t r\u1ec5\t th\u1ee9\t hai\t c\u1ee7a\t d\u00f2ng\t \u00fd\t t\u01b0\u1edfng\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i r\u1ed9ng.\t Nh\u01b0\t Mach\t \u0111\u00e3\t kh\u0103ng\t kh\u0103ng\t n\u00eau\t l\u00ean,\t \u0111i\u1ec3m\t sau\t \u0111\u00e2y\t trong thuy\u1ebft\tNewton\tl\u00e0\tkh\u00f4ng\tth\u1ecfa\t\u0111\u00e1ng:\tN\u1ebfu\tta\txem\tchuy\u1ec3n\t\u0111\u1ed9ng\tt\u1eeb quan\t \u0111i\u1ec3m\t thu\u1ea7n\t m\u00f4\t t\u1ea3,\t ch\u1ee9\t kh\u00f4ng\t ph\u1ea3i\t nh\u00e2n\t qu\u1ea3,\t th\u00ec\t ch\u1ec9\t c\u00f3 chuy\u1ec3n\t \u0111\u1ed9ng\t nh\u01b0\t l\u00e0\t chuy\u1ec3n\t \u0111\u1ed9ng\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t c\u1ee7a\t c\u00e1c\t v\u1eadt\t th\u1ec3\t v\u1edbi nhau.\t Nh\u01b0ng\t n\u1ebfu\t x\u00e9t\t t\u1eeb\t quan\t ni\u1ec7m\t c\u1ee7a\t chuy\u1ec3n\t \u0111\u1ed9ng\t t\u01b0\u01a1ng\t \u0111\u1ed1i th\u00ec\t gia\t t\u1ed1c\t xu\u1ea5t\t hi\u1ec7n\t trong\t c\u00e1c\t ph\u01b0\u01a1ng\t tr\u00ecnh\t chuy\u1ec3n\t \u0111\u1ed9ng Newton\t l\u00e0\t kh\u00f4ng\t th\u1ec3\t hi\u1ec3u\t \u0111\u01b0\u1ee3c.\t N\u00f3\t bu\u1ed9c\t Newton\t ph\u1ea3i\t ngh\u0129\t ra m\u1ed9t\t kh\u00f4ng\t gian\t v\u1eadt\t l\u00fd,\t \u0111\u1ec3\t \u0111\u1ed1i\t v\u1edbi\t n\u00f3\t gia\t t\u1ed1c\t t\u1ed3n\t t\u1ea1i\t c\u00f3\t \u00fd\t ngh\u0129a. 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Quan\t ni\u1ec7m\t n\u00e0y\t c\u1ee7a\t c\u00e1c\t ti\u00ean\t \u0111\u1ec1\t \u0111\u01b0\u1ee3c\t \u0111\u1ea1i\t di\u1ec7n\t b\u1edfi\t ti\u00ean\t \u0111\u1ec1\t h\u1ecdc hi\u1ec7n\t \u0111\u1ea1i\t \u0111\u00e3\t t\u1ea9y\t s\u1ea1ch\t to\u00e1n\t h\u1ecdc\t kh\u1ecfi\t t\u1ea5t\t c\u1ea3\t nh\u1eefng\t ph\u1ea7n\t t\u1eed\t n\u00e0o kh\u00f4ng\t thu\u1ed9c\t v\u1ec1\t n\u00f3,\t v\u00e0\t nh\u01b0\t th\u1ebf\t thanh\t to\u00e1n\t c\u00e1i\t t\u1ed1i\t t\u0103m\t huy\u1ec1n\t b\u00ed v\u1ed1n\tc\u00f3\ts\u1eb5n\ttr\u01b0\u1edbc\t\u0111\u00f3\ttrong\tc\u01a1\ts\u1edf\tc\u1ee7a\tto\u00e1n\th\u1ecdc.\tM\u1ed9t\tc\u00e1ch\ttr\u00ecnh\tb\u00e0y \u0111\u01b0\u1ee3c\t t\u1ea9y\t s\u1ea1ch\t nh\u01b0\t th\u1ebf\t c\u0169ng\t l\u00e0m\t cho\t hi\u1ec3n\t nhi\u00ean\t r\u1eb1ng\t to\u00e1n\t h\u1ecdc nh\u01b0\t t\u1ef1\t n\u00f3\t kh\u00f4ng\t \u0111\u1ee7\t kh\u1ea3\t n\u0103ng\t kh\u1eb3ng\t \u0111\u1ecbnh\t m\u1ed9t\t c\u00e1i\t g\u00ec\t v\u1ec1\t c\u00e1c\t \u0111\u1ed1i t\u01b0\u1ee3ng\t c\u1ee7a\t tr\u1ef1c\t gi\u00e1c\t hay\t c\u00e1c\t \u0111\u1ed1i\t t\u01b0\u1ee3ng\t c\u1ee7a[99]\t th\u1ef1c\t t\u1ea1i.\t Nh\u1eefng\t t\u1eeb ng\u1eef\tnh\u01b0\t\\\"\u0111i\u1ec3m\\\",\t\\\"\u0111\u01b0\u1eddng\tth\u1eb3ng\\\",\tv.v.\ttrong\th\u00ecnh\th\u1ecdc\tti\u00ean\t\u0111\u1ec1\tt\u01b0\u1ee3ng tr\u01b0ng\t cho\t nh\u1eefng\t s\u01a1\t \u0111\u1ed3\t kh\u00e1i\t ni\u1ec7m\t r\u1ed7ng\t v\u1ec1\t n\u1ed9i\t dung.\t C\u00e1i\t cho ch\u00fang\tn\u1ed9i\tdung\tkh\u00f4ng\tph\u1ea3i\tthu\u1ed9c\tv\u1ec1\tto\u00e1n\th\u1ecdc. 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Kh\u00f4ng\t ch\u1ec9\t h\u00ecnh\t h\u1ecdc\t th\u1ef1c\t ti\u1ec5n\t c\u1ee7a\t Euclid,\t m\u00e0\t c\u1ea3\t s\u1ef1\t kh\u00e1i\t qu\u00e1t g\u1ea7n\tnh\u1ea5t\tc\u1ee7a\tn\u00f3\tl\u00e0\th\u00ecnh\th\u1ecdc\tth\u1ef1c\tti\u1ec5n\tc\u1ee7a\tRiemann,\tv\u00e0\tc\u00f9ng\tv\u1edbi n\u00f3\tl\u00e0\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng,\t\u0111\u1ec1u\td\u1ef1a\ttr\u00ean\tgi\u1ea3\tthuy\u1ebft\tn\u00e0y.\tTrong s\u1ed1\tnh\u1eefng\tl\u00fd\tdo\tc\u1ee7a\tkinh\tnghi\u1ec7m\tbi\u1ec7n\tminh\tcho\ts\u1ef1\t\u0111\u00fang\t\u0111\u1eafn\tc\u1ee7a gi\u1ea3\t thi\u1ebft\t n\u00e0y,\t t\u00f4i\t ch\u1ec9\t mu\u1ed1n\t n\u00f3i\t \u0111\u1ebfn\t m\u1ed9t\t l\u00fd\t do\t th\u00f4i.\t Hi\u1ec7n\t t\u01b0\u1ee3ng truy\u1ec1n\t\u00e1nh\ts\u00e1ng\ttrong\tkh\u00f4ng\tgian\tr\u1ed7ng\tquy\tcho\tm\u1ed7i\tkho\u1ea3ng\tth\u1eddi gian\t c\u1ee5c\t b\u1ed9\t m\u1ed9t\t kho\u1ea3ng\t \u0111\u01b0\u1eddng,\t \u0111\u00f3\t l\u00e0\t \u0111\u01b0\u1eddng\t \u0111i\t c\u1ee7a\t \u00e1nh\t s\u00e1ng t\u01b0\u01a1ng\t\u1ee9ng,\tv\u00e0\tng\u01b0\u1ee3c\tl\u1ea1i.\tT\u1eeb\t\u0111\u00f3\tch\u00fang\tta\tsuy\tra,\tgi\u1ea3\tthi\u1ebft\tn\u00f3i\ttr\u00ean v\u1ec1\tc\u00e1c\t\u0111o\u1ea1n\t\u0111\u01b0\u1eddng\tc\u0169ng\t\u0111\u00fang\tcho\tc\u00e1c\tkho\u1ea3ng\tth\u1eddi\tgian\tc\u1ee7a\t\u0111\u1ed3ng h\u1ed3\ttrong\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i.\tCho\tn\u00ean\tn\u00f3\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\tdi\u1ec5n\t\u0111\u1ea1t\tnh\u01b0 sau:\tN\u1ebfu\thai\t\u0111\u1ed3ng\th\u1ed3\tl\u00fd\tt\u01b0\u1edfng\tch\u1ea1y\tnhanh\tb\u1eb1ng\tnhau\t\u1edf\tm\u1ed9t\tth\u1eddi \u0111i\u1ec3m\tv\u00e0\t\u1edf\t\u0111\u00e2u\t\u0111\u00f3\t(\t\u1edf\tg\u1ea7n\ttr\u1ef1c\tti\u1ebfp\tnhau),\tth\u00ec\tch\u00fang\ts\u1ebd\tlu\u00f4n\tlu\u00f4n ch\u1ea1y\t nhanh\t nh\u01b0\t nhau,\t b\u1ea5t\t c\u1ee9\t \u1edf\t \u0111\u00e2u\t v\u00e0\t v\u00e0o\t l\u00fac\t n\u00e0o\t ch\u00fang\t l\u1ea1i \u0111\u01b0\u1ee3c\tso\ts\u00e1nh\tv\u1edbi\tnhau\tt\u1ea1i\tc\u00f9ng\tm\u1ed9t\tch\u1ed7.\tN\u1ebfu\t\u0111\u1ecbnh\tl\u00fd\tn\u00e0y\tkh\u00f4ng \u0111\u00fang\t cho\t c\u00e1c\t \u0111\u1ed3ng\t h\u1ed3\t t\u1ef1\t nhi\u00ean,\t th\u00ec\t c\u00e1c\t t\u1ea7n\t s\u1ed1\t ri\u00eang\t c\u1ee7a\t c\u00e1c nguy\u00ean\t t\u1eed\t ri\u00eang\t l\u1ebb\t c\u1ee7a\t c\u00f9ng\t m\u1ed9t\t nguy\u00ean\t t\u1ed1\t h\u00f3a\t h\u1ecdc\t s\u1ebd\t kh\u00f4ng ph\u00f9\t h\u1ee3p\t nhau\t m\u1ed9t\t c\u00e1ch\t ch\u00ednh\t x\u00e1c\t nh\u01b0\t kinh\t nghi\u1ec7m\t ch\u1ee9ng minh.\tS\u1ef1\thi\u1ec7n\th\u1eefu\tc\u1ee7a\tc\u00e1c\tv\u1ea1ch\tquang\tph\u1ed5\ts\u1eafc\tn\u00e9t\tcung\tc\u1ea5p\tm\u1ed9t ch\u1ee9ng\tminh\tth\u1ef1c\t nghi\u1ec7m\tm\u1ed9t\t c\u00e1ch\tthuy\u1ebft\tph\u1ee5c\t cho\tnguy\u00ean\t l\u00fd \u0111\u00e3\tn\u00f3i\ttr\u00ean\tc\u1ee7a\th\u00ecnh\th\u1ecdc\tth\u1ef1c\tti\u1ec5n.\tCh\u00ednh\td\u1ef1a\ttr\u00ean\tc\u01a1\ts\u1edf\tn\u00e0y\tm\u00e0 ch\u00fang\t ta\t c\u00f3\t th\u1ec3\t n\u00f3i\t \u0111\u1ebfn\t m\u1ed9t\t metric\t Riemann\t c\u1ee7a\t continum kh\u00f4ng-th\u1eddi-gian\tb\u1ed1n\tchi\u1ec1u\tm\u1ed9t\tc\u00e1ch\tc\u00f3\t\u00fd\tngh\u0129a. C\u00e2u\th\u1ecfi,\tcontinum\tn\u00e0y\tl\u00e0\tEuclid\thay\t\u0111\u01b0\u1ee3c\tc\u1ea5u\ttr\u00fac\ttheo\ts\u01a1\t\u0111\u1ed3 t\u1ed5ng\t qu\u00e1t\t Riemann,\t hay\t theo\t c\u00e1i\t g\u00ec\t kh\u00e1c,\t c\u0103n\t c\u1ee9\t v\u00e0o\t quan\t \u0111i\u1ec3m \u0111\u01b0\u1ee3c\t\u0111\u1ea1i\tdi\u1ec7n\t\u1edf\t\u0111\u00e2y,\tl\u00e0\tm\u1ed9t\tc\u00e2u\th\u1ecfi\tth\u1ef1c\ts\u1ef1\tc\u00f3\tt\u00ednh\tch\u1ea5t\tv\u1eadt\tl\u00fd\tc\u1ea7n ph\u1ea3i\t\u0111\u01b0\u1ee3c\ttr\u1ea3\tl\u1eddi\tb\u1eb1ng\tkinh\tnghi\u1ec7m,\tch\u1ee9\tkh\u00f4ng\tph\u1ea3i\tm\u1ed9t\tc\u00e2u\th\u1ecfi c\u1ee7a\t quy\t \u01b0\u1edbc\t \u0111\u01b0\u1ee3c\t ch\u1ecdn\t thu\u1ea7n\t t\u00fay\t theo\t nh\u1eefng\t l\u00fd\t do\t th\u1ef1c\t d\u1ee5ng. 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Tuy\tnhi\u00ean,\tc\u00f2n\tm\u1ed9t\tcon\t\u0111\u01b0\u1eddng\tth\u1ee9\thai\t\u0111\u1ed1i\tv\u1edbi\tt\u00f4i\tl\u00e0\tc\u00f3\tth\u1ec3\td\u1ec5 \u0111i\th\u01a1n,\ttuy\tn\u00f3\tc\u0169ng\t\u0111\u1eb7t\tra\tnhi\u1ec1u\tkh\u00f3\tkh\u0103n\tl\u1edbn. Th\u1ef1c\tv\u1eady,\tn\u1ebfu\tch\u00fang\tta\th\u1ecfi\tv\u1ec1\tnh\u1eefng\ts\u1ef1\tkh\u00e1c\tbi\u1ec7t\tc\u1ee7a\tthuy\u1ebft t\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng\tr\u00fat\tra\tt\u1eeb\tnh\u1eefng\th\u1ec7\tqu\u1ea3\tquan\ts\u00e1t\t\u0111\u01b0\u1ee3c\ttrong\tthi\u00ean v\u0103n\t h\u1ecdc\t so\t v\u1edbi\t c\u00e1c\t h\u1ec7\t qu\u1ea3\t c\u1ee7a\t thuy\u1ebft\t Newton,\t th\u00ec\t tr\u01b0\u1edbc\t nh\u1ea5t ch\u00fang\tta\ts\u1ebd\tc\u00f3\tm\u1ed9t\ts\u1ef1\tkh\u00e1c\tbi\u1ec7t\tr\u00f5\tn\u00e9t\thi\u1ec7n\tra\ttrong\tv\u00f9ng\tc\u1eadn\tc\u1ee7a kh\u1ed1i\tl\u01b0\u1ee3ng\tl\u1edbn\th\u1ea5p\td\u1eabn,\tm\u1ed9t\ts\u1ef1\tkh\u00e1c\tbi\u1ec7t\t\u0111\u00e3\t\u0111\u01b0\u1ee3c\tx\u00e1c\tnh\u1eadn\t\u1edf\tSao Th\u1ee7y.\tTrong\ttr\u01b0\u1eddng\th\u1ee3p\tv\u0169\ttr\u1ee5\th\u1eefu\th\u1ea1n\tv\u1ec1\tkh\u00f4ng\tgian,\tc\u00f2n\tm\u1ed9t kh\u00e1c\tbi\u1ec7t\tth\u1ee9\thai\tso\tv\u1edbi\tthuy\u1ebft\tNewton,\t\u0111\u01b0\u1ee3c\tdi\u1ec5n\tt\u1ea3\ttrong\tng\u00f4n ng\u1eef\t c\u1ee7a\t thuy\u1ebft\t Newton\t nh\u01b0\t sau:\t Tr\u01b0\u1eddng\t h\u1ea5p\t d\u1eabn\t \u0111\u01b0\u1ee3c\t t\u1ea1o\t ra nh\u01b0\tth\u1ec3\tn\u00f3\tkh\u00f4ng\tph\u1ea3i\tl\u00e0\tk\u1ebft\tqu\u1ea3\tch\u1ec9\tc\u1ee7a\tc\u00e1c\tkh\u1ed1i\tl\u01b0\u1ee3ng\tc\u00f3\ttr\u1ecdng l\u01b0\u1ee3ng,\t m\u00e0\t c\u00f2n\t c\u1ee7a\t m\u1ed9t\t m\u1eadt\t \u0111\u1ed9\t kh\u1ed1i\t l\u01b0\u1ee3ng\t mang\t d\u1ea5u\t \u00e2m,\t \u0111\u01b0\u1ee3c ph\u00e2n\t ph\u1ed1i\t \u0111\u1ec1u\t trong\t kh\u00f4ng\t gian.\t V\u00ec\t m\u1eadt\t \u0111\u1ed9\t kh\u1ed1i\t l\u01b0\u1ee3ng\t gi\u1ea3\t \u0111\u1ecbnh n\u00e0y\t ph\u1ea3i\t l\u00e0\t c\u1ef1c\t nh\u1ecf,\t n\u00ean\t n\u00f3\t ch\u1ec9\t c\u00f3\t th\u1ec3\t \u0111\u00e1ng\t k\u1ec3\t trong\t nh\u1eefng\t h\u1ec7 th\u1ed1ng\th\u1ea5p\td\u1eabn\tc\u00f3\tquy\tm\u00f4\tr\u1ea5t\tr\u1ed9ng."]