Thuyết Tương Đối Hẹp Và Rộng Của Albert Einstein

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M\u1ed7i\t s\u1ef1\t m\u00f4\t t\u1ea3\t v\u1ec1\t kh\u00f4ng\t gian\t c\u1ee7a\t v\u1ecb\t tr\u00ed\t c\u1ee7a\t m\u1ed9t\t s\u1ef1\t ki\u1ec7n[16]\t hay \u0111\u1ed1i\tt\u01b0\u1ee3ng,\t\u0111\u01b0\u1ee3c\tth\u1ef1c\thi\u1ec7n\tkhi\tng\u01b0\u1eddi\tta\tcho\tbi\u1ebft\t\u0111i\u1ec3m\tc\u1ee7a\tm\u1ed9t\tv\u1eadt th\u1ec3\tr\u1eafn\t(v\u1eadt\tth\u1ec3\tquy\tchi\u1ebfu)\ttr\u00f9ng\tv\u1edbi\ts\u1ef1\tki\u1ec7n\tkia.\t\u0110i\u1ec1u\tn\u00e0y\tkh\u00f4ng nh\u1eefng\t \u0111\u00fang\t cho\t s\u1ef1\t m\u00f4\t t\u1ea3\t khoa\t h\u1ecdc\t m\u00e0\t c\u00f2n\t cho\t cu\u1ed9c\t s\u1ed1ng\t h\u00e0ng ng\u00e0y.\t N\u1ebfu\t t\u00f4i\t ph\u00e2n\t t\u00edch\t s\u1ef1\t ch\u1ec9\t b\u00e1o\t v\u1ecb\t tr\u00ed[17]\t \\\"Qu\u1ea3ng\t tr\u01b0\u1eddng\t M\u00ea Linh\tt\u1ea1i\tTh\u00e0nh\tph\u1ed1\tH\u1ed3\tCh\u00ed\tMinh\\\"[18]\tth\u00ec\tn\u00f3\tc\u00f3\tngh\u0129a\tnh\u01b0\tsau:\tM\u1eb7t \u0111\u1ea5t\t l\u00e0\t m\u1ed9t\t v\u1eadt\t th\u1ec3\t r\u1eafn\t tr\u00ean\t \u0111\u00f3\t th\u00f4ng\t tin\t v\u1ec1\t v\u1ecb\t tr\u00ed\t \u0111\u01b0\u1ee3c\t cho\t bi\u1ebft (quy\t chi\u1ebfu);\t \u1edf\t \u0111\u00f3\t \\\"Qu\u1ea3ng\t tr\u01b0\u1eddng\t M\u00ea\t Linh\t t\u1ea1i\t Th\u00e0nh\t ph\u1ed1\t H\u1ed3\t Ch\u00ed Minh\\\"\tl\u00e0\tm\u1ed9t\t\u0111i\u1ec3m\t\u0111\u01b0\u1ee3c\t\u0111\u00e1nh\td\u1ea5u\tv\u00e0\t\u0111\u01b0\u1ee3c\tg\u1eafn\tm\u1ed9t\tc\u00e1i\tt\u00ean,\t\u0111i\u1ec3m m\u00e0\ts\u1ef1\tki\u1ec7n\tkia\ttr\u00f9ng\tkh\u1edbp\tv\u1ec1\tkh\u00f4ng\tgian\tv\u1edbi\tn\u00f3[19]. C\u00e1ch\t x\u00e1c\t \u0111\u1ecbnh\t v\u1ecb\t tr\u00ed\t th\u00f4\t thi\u1ec3n\t n\u00e0y\t ch\u1ec9\t bi\u1ebft\t \u0111\u1ebfn\t c\u00e1c\t v\u1ecb\t tr\u00ed\t \u1edf\t b\u1ec1 m\u1eb7t\tc\u1ee7a\tc\u00e1c\tv\u1eadt\tth\u1ec3\tr\u1eafn\tv\u00e0\tn\u00f3\tg\u1eafn\tli\u1ec1n\tv\u1edbi\ts\u1ef1\thi\u1ec7n\th\u1eefu\tc\u1ee7a\tnhi\u1ec1u \u0111i\u1ec3m\t c\u00f3\t th\u1ec3\t ph\u00e2n\t bi\u1ec7t\t \u0111\u01b0\u1ee3c\t c\u1ee7a\t b\u1ec1\t m\u1eb7t\t n\u00e0y.\t Ch\u00fang\t ta\t h\u00e3y\t xem tinh\tth\u1ea7n\tcon\tng\u01b0\u1eddi\tt\u1ef1\tgi\u1ea3i\tph\u00f3ng\tkh\u1ecfi\thai\tgi\u1edbi\th\u1ea1n\tn\u00e0y\tnh\u01b0\tth\u1ebf n\u00e0o\tm\u00e0\tkh\u00f4ng\tl\u00e0m\tcho\tb\u1ea3n\tch\u1ea5t\tc\u1ee7a\tc\u00e1ch\tx\u00e1c\t\u0111\u1ecbnh\tv\u1ecb\ttr\u00ed\tthay\t\u0111\u1ed5i! N\u1ebfu\t ch\u1eb3ng\t h\u1ea1n\t tr\u00ean\t Qu\u1ea3ng\t tr\u01b0\u1eddng\t M\u00ea\t Linh\t c\u00f3\t m\u1ed9t\t \u0111\u00e1m\t m\u00e2y\t l\u01a1 l\u1eedng,\t th\u00ec\t v\u1ecb\t tr\u00ed\t c\u1ee7a\t \u0111\u00e1m\t m\u00e2y\t n\u00e0y,\t quy\t v\u1ec1\t b\u1ec1\t m\u1eb7t\t qu\u1ea3\t \u0111\u1ea5t,\t c\u00f3\t th\u1ec3 \u0111\u01b0\u1ee3c\tx\u00e1c\t\u0111\u1ecbnh\tb\u1eb1ng\tc\u00e1ch\tng\u01b0\u1eddi\tta\tthi\u1ebft\tl\u1eadp\tt\u1ea1i\tqu\u1ea3ng\ttr\u01b0\u1eddng\tm\u1ed9t c\u00e1i\t s\u00e0o\t th\u1eb3ng\t g\u00f3c,\t v\u00e0\t cao\t \u0111\u1ebfn\t \u0111\u00e1m\t m\u00e2y.\t Chi\u1ec1u\t d\u00e0i\t c\u1ee7a\t c\u00e2y\t s\u00e0o, \u0111\u01b0\u1ee3c\t\u0111o\tv\u1edbi\tm\u1ed9t\tthanh\t\u0111o\t\u0111\u01a1n\tv\u1ecb\tchu\u1ea9n,\tc\u00f9ng\tv\u1edbi\ts\u1ef1\tx\u00e1c\t\u0111\u1ecbnh\tv\u1ecb tr\u00ed\t c\u1ee7a\t \u0111i\u1ec3m\t ch\u00e2n\t c\u1ee7a\t c\u00e2y\t s\u00e0o,\t l\u00e0m\t th\u00e0nh\t s\u1ef1\t x\u00e1c\t \u0111\u1ecbnh\t \u0111\u1ea7y\t \u0111\u1ee7\t v\u1ecb tr\u00ed\tc\u1ee7a\t\u0111\u00e1m\tm\u00e2y.\tQua\tth\u00ed\td\u1ee5\tn\u00e0y,\tch\u00fang\tta\tth\u1ea5y\tc\u00e1ch\tth\u1ee9c\tm\u00e0\ts\u1ef1 tinh\tt\u1ebf\th\u00f3a\tc\u1ee7a\tkh\u00e1i\tni\u1ec7m\tv\u1ecb\ttr\u00ed\t\u0111\u00e3\tdi\u1ec5n\tra. a)\tCh\u00fang\tta\tn\u1edbi\tr\u1ed9ng\tra\tv\u1eadt\tth\u1ec3\tr\u1eafn,\tnh\u01b0\tl\u00e0\th\u1ec7\tquy\tchi\u1ebfu\tcho\ts\u1ef1","x\u00e1c\t\u0111\u1ecbnh\tv\u1ecb\ttr\u00ed,\tsao\tcho\tv\u1eadt\tth\u1ec3\tr\u1eafn\t\u0111\u01b0\u1ee3c\tn\u1edbi\tr\u1ed9ng\tkia\tb\u1eaft\tg\u1eb7p\t\u0111\u1ed1i t\u01b0\u1ee3ng\tc\u1ea7n\t\u0111\u01b0\u1ee3c\t\u0111\u1ecbnh\tv\u1ecb. b)\t \u0110\u1ec3\t \u0111\u1eb7c\t tr\u01b0ng\t v\u1ecb\t tr\u00ed,\t ng\u01b0\u1eddi\t ta\t s\u1eed\t d\u1ee5ng\t con\t s\u1ed1\t (\u1edf\t \u0111\u00e2y\t l\u00e0\t chi\u1ec1u d\u00e0i\t c\u1ee7a\t c\u00e2y\t s\u00e0o\t \u0111\u01b0\u1ee3c\t \u0111o\t b\u1eb1ng\t thanh\t \u0111o)\t thay\t v\u00ec\t c\u00e1c\t \u0111i\u1ec3m\t \u0111\u01b0\u1ee3c \u0111\u00e1nh\td\u1ea5u. c)\t Ch\u00fang\t ta\t v\u1eabn\t n\u00f3i\t \u0111\u1ebfn\t chi\u1ec1u\t cao\t c\u1ee7a\t \u0111\u00e1m\t m\u00e2y,\t ngay\t c\u1ea3\t khi c\u00e2y\ts\u00e0o\t\u0111o,\t\u0111\u00e1ng\tl\u1ebd\tph\u1ea3i\tcao\t\u0111\u1ebfn\t\u0111\u00e1m\tm\u00e2y,\tkh\u00f4ng\t\u0111\u01b0\u1ee3c\td\u1ef1ng\tl\u00ean. Trong\t tr\u01b0\u1eddng\t h\u1ee3p\t c\u1ee7a\t ch\u00fang\t ta,\t b\u1eb1ng\t nh\u1eefng\t c\u00e1ch\t quan\t s\u00e1t quang\th\u1ecdc\t\u0111\u00e1m\tm\u00e2y\tt\u1eeb\tnhi\u1ec1u\tv\u1ecb\ttr\u00ed\tkh\u00e1c\tnhau\tt\u1eeb\tm\u1eb7t\t\u0111\u1ea5t,\tv\u00e0\t\u0111\u1ebf\t\u00fd \u0111\u1ebfn\t nh\u1eefng\t t\u00ednh\t ch\u1ea5t\t truy\u1ec1n\t c\u1ee7a\t \u00e1nh\t s\u00e1ng,\t ch\u00fang\t ta\t x\u00e1c\t \u0111\u1ecbnh \u0111\u01b0\u1ee3c\tc\u00e1i\ts\u00e0o\tkia\tc\u1ea7n\tph\u1ea3i\td\u00e0i\tbao\tnhi\u00eau\t\u0111\u1ec3\t\u0111\u1ea1t\tt\u1edbi\t\u0111\u00e1m\tm\u00e2y. T\u1eeb\t suy\t ngh\u0129\t n\u00e0y\t ch\u00fang\t ta\t th\u1ea5y\t r\u1eb1ng\t \u0111\u1ec3\t m\u00f4\t t\u1ea3\t v\u1ecb\t tr\u00ed,\t ch\u00fang\t ta c\u00f3\tl\u1ee3i\th\u01a1n\tn\u1ebfu\tc\u00f3\tth\u1ec3\ts\u1eed\td\u1ee5ng\tc\u00e1c\ts\u1ed1\t\u0111o,\t\u0111\u1ec3\tl\u00e0m\tcho\tm\u00ecnh\t\u0111\u1ed9c\tl\u1eadp v\u1edbi\t s\u1ef1\t t\u1ed3n\t t\u1ea1i\t c\u1ee7a\t nh\u1eefng\t \u0111i\u1ec3m\t \u0111\u01b0\u1ee3c\t \u0111\u00e1nh\t d\u1ea5u\t tr\u00ean\t v\u1eadt\t th\u1ec3\t r\u1eafn quy\t chi\u1ebfu.\t V\u1eadt\t l\u00fd\t \u0111o\t \u0111\u1ea1c\t th\u1ef1c\t hi\u1ec7n\t \u0111\u01b0\u1ee3c\t \u0111i\u1ec1u\t n\u00e0y\t b\u1eb1ng\t vi\u1ec7c\t \u00e1p d\u1ee5ng\th\u1ec7\tth\u1ed1ng\tt\u1ecda\t\u0111\u1ed9\tDescartes\t(\u0110\u1ec1-C\u00e1c). H\u1ec7\tth\u1ed1ng\tt\u1ecda\t\u0111\u1ed9\tn\u00e0y\tbao\tg\u1ed3m\tba\tm\u1eb7t\tph\u1eb3ng\tth\u1eb3ng\tg\u00f3c\tnhau\tv\u00e0 g\u1eafn\tv\u00e0o\tm\u1ed9t\tv\u1eadt\tth\u1ec3\tr\u1eafn.\tV\u1ecb\ttr\u00ed\tc\u1ee7a\tm\u1ed9t\ts\u1ef1\tki\u1ec7n\tb\u1ea5t\tk\u1ef3\t\u0111\u1ed1i\tv\u1edbi\th\u1ec7 t\u1ecda\t \u0111\u1ed9\t (v\u1ec1\t c\u01a1\t b\u1ea3n)\t s\u1ebd\t \u0111\u01b0\u1ee3c\t m\u00f4\t t\u1ea3\t b\u1eb1ng\t s\u1ef1\t x\u00e1c\t \u0111\u1ecbnh\t chi\u1ec1u\t d\u00e0i\t c\u1ee7a ba\t \u0111o\u1ea1n,\t hay\t c\u1ee7a\t t\u1ecda\t \u0111\u1ed9\t (x,\t y,\t z),\t (so\t s\u00e1nh\t \u1ea3nh\t 2,\t tr.\t 34),\t ch\u1ea1y th\u1eb3ng\tg\u00f3c\tt\u1eeb\ts\u1ef1\tki\u1ec7n\txu\u1ed1ng\tc\u00e1c\tm\u1eb7t\tph\u1eb3ng.\tChi\u1ec1u\td\u00e0i\tc\u1ee7a\tba\t\u0111o\u1ea1n th\u1eb3ng\tg\u00f3c\tn\u00e0y\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\tx\u00e1c\t\u0111\u1ecbnh\tb\u1edfi\tm\u1ed9t\tlo\u1ea1t\tthao\tt\u00e1c\tv\u1edbi\tc\u00e1c thanh\t \u0111o\t r\u1eafn,\t \u0111\u01b0\u1ee3c\t quy\t \u0111\u1ecbnh\t b\u1edfi\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t v\u00e0\t ph\u01b0\u01a1ng\t ph\u00e1p c\u1ee7a\th\u00ecnh\th\u1ecdc\tEuclid. Trong\tth\u1ef1c\tt\u1ebf,\tc\u00e1c\tm\u1eb7t\tph\u1eb3ng\tr\u1eafn\tkia\tl\u00e0m\tn\u00ean\th\u1ec7\tth\u1ed1ng\tt\u1ecda\t\u0111\u1ed9 th\u01b0\u1eddng\t kh\u00f4ng\t \u0111\u01b0\u1ee3c\t th\u1ef1c\t hi\u1ec7n;\t c\u00e1c\t t\u1ecda\t \u0111\u1ed9\t c\u0169ng\t kh\u00f4ng\t \u0111\u01b0\u1ee3c\t x\u00e1c \u0111\u1ecbnh\tth\u1ef1c\ts\u1ef1\tb\u1eb1ng\tc\u00e1ch\t\u0111o\t\u0111\u1ea1c\tv\u1edbi\tnh\u1eefng\tthanh\t\u0111o\tr\u1eafn,\tm\u00e0\tb\u1eb1ng nh\u1eefng\tc\u00e1ch\tgi\u00e1n\tti\u1ebfp.\tTuy\tnhi\u00ean\t\u00fd\tngh\u0129a\tv\u1eadt\tl\u00fd\tc\u1ee7a\tc\u00e1c\tth\u00f4ng\ts\u1ed1 v\u1ec1\t v\u1ecb\t tr\u00ed\t ph\u1ea3i\t lu\u00f4n\t lu\u00f4n\t \u0111\u01b0\u1ee3c\t b\u1ea3o\t \u0111\u1ea3m\t cho\t ph\u00f9\t h\u1ee3p\t v\u1edbi\t nh\u1eefng suy\tngh\u0129\ttr\u00ean,\tn\u1ebfu\tc\u00e1c\tk\u1ebft\tqu\u1ea3\tc\u1ee7a\tv\u1eadt\tl\u00fd\tv\u00e0\tthi\u00ean\tv\u0103n\th\u1ecdc\tmu\u1ed1n duy\ttr\u00ec\ts\u1ef1\ts\u00e1ng\ts\u1ee7a\tc\u1ee7a\tch\u00fang[20]. Do\t \u0111\u00f3\t ch\u00fang\t ta\t c\u00f3\t k\u1ebft\t lu\u1eadn\t sau\t \u0111\u00e2y:\t M\u1ed7i\t m\u1ed9t\t s\u1ef1\t m\u00f4\t t\u1ea3\t v\u1ec1 kh\u00f4ng\tgian\tc\u1ee7a\tc\u00e1c\ts\u1ef1\tki\u1ec7n\t\u0111\u1ec1u\ts\u1eed\td\u1ee5ng\tm\u1ed9t\tv\u1eadt\tth\u1ec3\tr\u1eafn,\ttr\u00ean\t\u0111\u00f3 c\u00e1c\ts\u1ef1\tki\u1ec7n\t\u0111\u01b0\u1ee3c\tquy\tchi\u1ebfu.\tM\u1ed1i\tli\u00ean\th\u1ec7\t\u0111\u00f3\tb\u1ea3o\t\u0111\u1ea3m\tr\u1eb1ng\tc\u00e1c\t\u0111\u1ecbnh lu\u1eadt\t h\u00ecnh\t h\u1ecdc\t Euclid\t l\u00e0\t \u0111\u00fang\t cho\t c\u00e1c\t \\\"kho\u1ea3ng\t c\u00e1ch\\\",\t v\u00e0\t \\\"kho\u1ea3ng c\u00e1ch\\\"\t\u0111\u01b0\u1ee3c\tbi\u1ec3u\tth\u1ecb\tv\u1ec1\tm\u1eb7t\tv\u1eadt\tl\u00fd\th\u1ecdc\tb\u1eb1ng\thai\t\u0111\u1ea7u\tm\u1ed1c\ttr\u00ean\tm\u1ed9t","v\u1eadt\tth\u1ec3\tr\u1eafn.","\u00a7\t3 Kh\u00f4ng\tGian\tv\u00e0\tTh\u1eddi\tGian\ttrong\tC\u01a1\tH\u1ecdc\tC\u1ed5\t\u0110i\u1ec3n N\u1ebfu\t kh\u00f4ng\t c\u00f3\t m\u1ed9t\t s\u1ef1\t suy\t t\u01b0\t nghi\u00eam\t ch\u1ec9nh\t v\u00e0\t nh\u1eefng\t l\u1eddi\t gi\u1ea3i th\u00edch\tchi\tti\u1ebft\tv\u1ec1\tnhi\u1ec7m\tv\u1ee5\tc\u1ee7a\tc\u01a1\th\u1ecdc,\t\\\"l\u00e0\tbi\u1ec3u\tth\u1ecb\tc\u00e1c\tv\u1eadt\tth\u1ec3\tthay \u0111\u1ed5i\t v\u1ecb\t tr\u00ed\t c\u1ee7a\t ch\u00fang\t trong\t kh\u00f4ng\t gian\t theo\t th\u1eddi\t gian\t nh\u01b0\t th\u1ebf n\u00e0o\\\",\tth\u00ec\tl\u01b0\u01a1ng\tt\u00e2m\tt\u00f4i\ts\u1ebd\tc\u1ea3m\tth\u1ea5y\tt\u1ed9i\tl\u1ed7i\ttr\u01b0\u1edbc\ttinh\tth\u1ea7n\tthi\u00eang li\u00eang\tc\u1ee7a\ts\u1ef1\tminh\tb\u1ea1ch.\tNh\u1eefng\tt\u1ed9i\tdanh\tn\u00e0y\ttr\u01b0\u1edbc\th\u1ebft\tph\u1ea3i\t\u0111\u01b0\u1ee3c \u0111\u01b0a\tra\t\u00e1nh\ts\u00e1ng. \u1ede\t \u0111\u00e2y\t \\\"v\u1ecb\t tr\u00ed\\\"\t v\u00e0\t \\\"kh\u00f4ng\t gian\\\"\t \u0111\u01b0\u1ee3c\t hi\u1ec3u\t l\u00e0\t g\u00ec,\t \u0111i\u1ec1u\t \u0111\u00f3\t ch\u01b0a\t r\u00f5 r\u00e0ng.\t T\u00f4i\t \u0111\u1ee9ng\t \u1edf\t c\u1ee7a\t s\u1ed5\t c\u1ee7a\t 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chuy\u1ec3n\t\u0111\u1ed9ng\ttr\u00f2n.\tM\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9,\tm\u00e0\ttr\u1ea1ng\tth\u00e1i\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a n\u00f3\tc\u00f3\tt\u00ednh\tch\u1ea5t\tnh\u01b0\tth\u1ebf,\t\u0111\u1ec3\tcho\t\u0111\u1ed1i\tv\u1edbi\tn\u00f3\t\u0111\u1ecbnh\tlu\u1eadt\tqu\u00e1n\tt\u00ednh\tc\u00f3 hi\u1ec7u\t l\u1ef1c,\t ch\u00fang\t ta\t g\u1ecdi\t l\u00e0\t m\u1ed9t\t \\\"h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t Galilei\\\".\t Ch\u1ec9\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed9t h\u1ec7\tt\u1ecda\t\u0111\u1ed9\tGalilei\tth\u00ec\tc\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tc\u1ee7a\tc\u01a1\th\u1ecdc\tGalilei\t-\tNewton\tm\u1edbi \u0111\u01b0\u1ee3c\txem\tl\u00e0\tc\u00f3\thi\u1ec7u\tl\u1ef1c.","\u00a7\t5 Nguy\u00ean\tL\u00fd\tT\u01b0\u01a1ng\t\u0110\u1ed1i\t(Theo\tNgh\u0129a\tH\u1eb9p) Ch\u00fang\tta\tl\u1ea1i\txu\u1ea5t\tph\u00e1t\tt\u1eeb\tth\u00ed\td\u1ee5\tc\u1ee7a\tchi\u1ebfc\txe\tl\u1eeda\tch\u1ea1y\tv\u1edbi\tv\u1eadn t\u1ed1c\t \u0111\u1ec1u,\t \u0111\u1ec3\t c\u00f3\t \u0111\u01b0\u1ee3c\t s\u1ef1\t r\u00f5\t r\u00e0ng\t l\u1edbn\t nh\u01b0\t c\u00f3\t th\u1ec3.\t Ch\u00fang\t ta\t g\u1ecdi chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t n\u00f3\t l\u00e0\t chuy\u1ec3n\t \u0111\u1ed9ng\t t\u1ecbnh\t ti\u1ebfn\t \u0111\u1ec1u\t (\\\"\u0111\u1ec1u\\\"\t v\u00ec\t v\u1eadn t\u1ed1c\t v\u00e0\t h\u01b0\u1edbng\t c\u1ee7a\t n\u00f3\t kh\u00f4ng\t thay\t \u0111\u1ed5i,\t \\\"chuy\u1ec3n\t \u0111\u1ed9ng\t t\u1ecbnh\t ti\u1ebfn\\\"\t v\u00ec xe\t tuy\t thay\t \u0111\u1ed5i\t v\u1ecb\t tr\u00ed\t \u0111\u1ed1i\t v\u1edbi\t n\u1ec1n\t ray\t nh\u01b0ng\t n\u00f3\t kh\u00f4ng\t th\u1ef1c\t hi\u1ec7n chuy\u1ec3n\t \u0111\u1ed9ng\t quay).\t Ch\u00fang\t ta\t t\u01b0\u1edfng\t t\u01b0\u1ee3ng\t m\u1ed9t\t con\t qu\u1ea1\t bay th\u1eb3ng\tv\u00e0\t\u0111\u1ec1u\ttrong\tkh\u00f4ng\tkh\u00ed\t-\tn\u1ebfu\tch\u00fang\tta\tquan\ts\u00e1t\tt\u1eeb\tn\u1ec1n\tray. Quan\t s\u00e1t\t t\u1eeb\t chi\u1ebfc\t xe\t ch\u1ea1y,\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t con\t qu\u1ea1\t l\u00e0\t m\u1ed9t chuy\u1ec3n\t \u0111\u1ed9ng\t tuy\t v\u1edbi\t v\u1eadn\t t\u1ed1c\t v\u00e0\t ph\u01b0\u01a1ng\t h\u01b0\u1edbng\t kh\u00e1c,\t nh\u01b0ng\t n\u00f3 c\u0169ng\t l\u00e0\t th\u1eb3ng\t v\u00e0\t \u0111\u1ec1u.\t Di\u1ec5n\t t\u1ea3\t m\u1ed9t\t c\u00e1ch\t tr\u1eebu\t t\u01b0\u1ee3ng:\t M\u1ed9t\t kh\u1ed1i l\u01b0\u1ee3ng\tm\tchuy\u1ec3n\t\u0111\u1ed9ng\tth\u1eb3ng\tv\u00e0\t\u0111\u1ec1u\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tK,\t th\u00ec n\u00f3\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u0169ng\tth\u1eb3ng\tv\u00e0\t\u0111\u1ec1u\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tth\u1ee9\thai K\u2019,\t n\u1ebfu\t h\u1ec7\t n\u00e0y\t c\u00f3\t m\u1ed9t\t chuy\u1ec3n\t \u0111\u1ed9ng\t t\u1ecbnh\t ti\u1ebfn\t \u0111\u1ec1u\t \u0111\u1ed1i\t v\u1edbi\t K.\t T\u1eeb \u0111\u00e2y\t ch\u00fang\t ta\t c\u00f3\t k\u1ebft\t lu\u1eadn,\t ph\u00f9\t h\u1ee3p\t v\u1edbi\t tr\u00ecnh\t b\u00e0y\t c\u1ee7a\t ch\u01b0\u01a1ng tr\u01b0\u1edbc: N\u1ebfu\t K\t l\u00e0\t m\u1ed9t\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t Galilei,\t th\u00ec\t m\u1ed7i\t m\u1ed9t\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t kh\u00e1c\t K' c\u0169ng\t l\u00e0\t Galilei,\t n\u1ebfu\t h\u1ec7\t \u0111\u00f3\t \u1edf\t trong\t tr\u1ea1ng\t th\u00e1i\t m\u1ed9t\t chuy\u1ec3n\t \u0111\u1ed9ng t\u1ecbnh\tti\u1ebfn\t\u0111\u1ec1u\t\u0111\u1ed1i\tv\u1edbi\tK.\tC\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tc\u1ee7a\tc\u01a1\th\u1ecdc\tGalilei\t-\tNewton c\u00f3\tgi\u00e1\ttr\u1ecb\t\u0111\u1ed1i\tv\u1edbi\tK\u2019,\tc\u0169ng\tnh\u01b0\t\u0111\u1ed1i\tv\u1edbi\tK. Ch\u00fang\tta\t\u0111i\tth\u00eam\tm\u1ed9t\tb\u01b0\u1edbc\tn\u1eefa\ttrong\tvi\u1ec7c\tt\u1ed5ng\tqu\u00e1t\th\u00f3a\tb\u1eb1ng c\u00e1ch\t ph\u00e1t\t bi\u1ec3u\t nguy\u00ean\t l\u00fd:\t N\u1ebfu\t K'\t l\u00e0\t m\u1ed9t\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t chuy\u1ec3n\t \u0111\u1ed9ng \u0111\u1ec1u\t v\u00e0\t kh\u00f4ng\t quay\t \u0111\u1ed1i\t v\u1edbi\t K\t th\u00ec\t c\u00e1c\t s\u1ef1\t ki\u1ec7n\t t\u1ef1\t nhi\u00ean\t \u0111\u1ed1i\t v\u1edbi\t K\u2019 di\u1ec5n\tbi\u1ebfn\ttheo\tc\u00f9ng\tc\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tt\u1ed5ng\tqu\u00e1t\tnh\u01b0\t\u0111\u1ed1i\tv\u1edbi\tK.\tT\u00ednh ch\u1ea5t\tn\u00e0y\tch\u00fang\tta\tg\u1ecdi\tl\u00e0\tNguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\t(theo\tngh\u0129a\th\u1eb9p). Ch\u1eebng\tn\u00e0o\tng\u01b0\u1eddi\tta\tc\u00f2n\ttin\tr\u1eb1ng\tt\u1ea5t\tc\u1ea3\tc\u00e1c\ts\u1ef1\tki\u1ec7n\tthi\u00ean\tnhi\u00ean \u0111\u01b0\u1ee3c\tm\u00f4\tt\u1ea3\tb\u1eb1ng\tc\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n,\tth\u00ec\tng\u01b0\u1eddi\tta\tkh\u00f4ng\tth\u1ec3\tnghi\tng\u1edd hi\u1ec7u\t l\u1ef1c\t c\u1ee7a\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed5i\t n\u00e0y.\t Tuy\t nhi\u00ean,\t v\u1edbi\t s\u1ef1\t ph\u00e1t tri\u1ec3n\t m\u1edbi\t c\u1ee7a\t \u0111i\u1ec7n\t \u0111\u1ed9ng\t h\u1ecdc\t v\u00e0\t quang\t h\u1ecdc\t th\u00ec\t r\u00f5\t r\u00e0ng\t c\u01a1\t h\u1ecdc\t c\u1ed5 \u0111i\u1ec3n\t ng\u00e0y\t c\u00e0ng\t kh\u00f4ng\t c\u00f2n\t l\u00e0\t n\u1ec1n\t t\u1ea3ng\t \u0111\u1ea7y\t \u0111\u1ee7\t c\u1ee7a\t m\u1ecdi\t s\u1ef1\t m\u00f4\t t\u1ea3 t\u1ef1\t nhi\u00ean.\t Do\t \u0111\u00f3\t c\u00e2u\t h\u1ecfi\t v\u1ec1\t hi\u1ec7u\t l\u1ef1c\t c\u1ee7a\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t tr\u1edf th\u00e0nh\tv\u1ea5n\t\u0111\u1ec1\t\u0111\u00e1ng\tth\u1ea3o\tlu\u1eadn.\tV\u00e0\tng\u01b0\u1eddi\tta\tkh\u00f4ng\tlo\u1ea1i\ttr\u1eeb\tc\u00e2u\ttr\u1ea3 l\u1eddi\tc\u00f3\tth\u1ec3\tl\u00e0\tph\u1ee7\t\u0111\u1ecbnh. 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N\u00eau\tgi\u1edd\tt\u00f4i\th\u1ecfi,\tb\u1ea1n\t\u0111\u1ecdc\tth\u00e2n\tm\u1ebfn,\tr\u1eb1ng\tc\u00e2u\tn\u00f3i\t\u0111\u00f3\tc\u00f3\t\u00fd\tngh\u0129a\tg\u00ec kh\u00f4ng,\t th\u00ec\t b\u1ea1n\t s\u1ebd\t tr\u1ea3\t l\u1eddi\t \\\"c\u00f3\\\"\t m\u1ed9t\t c\u00e1ch\t v\u1eefng\t tin.\t Nh\u01b0ng\t n\u1ebfu\t t\u00f4i ti\u1ebfn\tth\u00eam\tm\u1ed9t\tb\u01b0\u1edbc\tn\u1eefa,\ty\u00eau\tc\u1ea7u\tb\u1ea1n\tgi\u1ea3i\tth\u00edch\t\u00fd\tngh\u0129a\tc\u1ee7a\tc\u00e2u n\u00f3i\tm\u1ed9t\tc\u00e1ch\tch\u00ednh\tx\u00e1c\th\u01a1n,\tth\u00ec\tsau\tv\u00e0i\tl\u00fac\tsuy\tngh\u0129,\tb\u1ea1n\ts\u1ebd\tnh\u1eadn th\u1ea5y\tr\u1eb1ng,\tc\u00e2u\ttr\u1ea3\tl\u1eddi\tcho\tc\u00e2u\th\u1ecfi\tn\u00e0y\tkh\u00f4ng\t\u0111\u01a1n\tgi\u1ea3n\tnh\u01b0\tb\u1ea1n\t\u0111\u00e3 t\u01b0\u1edfng\tban\t\u0111\u1ea7u. 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N\u1ebfu\t thay\t v\u00ec\t \u0111\u1ecbnh\t lu\u1eadt\t truy\u1ec1n\t \u00e1nh\t s\u00e1ng,\t ch\u00fang\t ta\t \u0111\u1eb7t\t nh\u1eefng gi\u1ea3\t\u0111\u1ecbnh\t\u0111\u01b0\u1ee3c\thi\u1ec3u\tng\u1ea7m\tc\u1ee7a\tc\u01a1\th\u1ecdc\tc\u0169\tv\u1ec1\tb\u1ea3n\tch\u1ea5t\ttuy\u1ec7t\t\u0111\u1ed1i\tc\u1ee7a th\u1eddi\t gian\t v\u00e0\t chi\u1ec1u\t d\u00e0i\t l\u00e0m\t n\u1ec1n\t t\u1ea3ng,\t th\u00ec,\t thay\t v\u00ec\t nh\u1eefng\t ph\u01b0\u01a1ng tr\u00ecnh\tbi\u1ebfn\t\u0111\u1ed5i\ttr\u00ean,\tch\u00fang\tta\ts\u1ebd\t\u0111i\t\u0111\u1ebfn\tc\u00e1c\tph\u01b0\u01a1ng\ttr\u00ecnh\td\u1ea1ng: x'\t=\tx\t-\tvt y\u2019\t=\ty z\u2019\t=\tz t\u2019\t=\tt H\u1ec7\t th\u1ed1ng\t ph\u01b0\u01a1ng\t tr\u00ecnh\t th\u01b0\u1eddng\t \u0111\u01b0\u1ee3c\t g\u1ecdi\t l\u00e0\t \\\"Ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i Galilei\\\".\tPh\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tGalilei\tc\u00f3\tth\u1ec3\t\u0111\u01b0\u1ee3c\tsuy\tra\tt\u1eeb\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i Lorentz\tb\u1eb1ng\tc\u00e1ch\t\u1edf\t\u0111\u00f3\tng\u01b0\u1eddi\tta\tcho\tv\u1eadn\tt\u1ed1c\t\u00e1nh\ts\u00e1ng\tc\tb\u1eb1ng\tv\u00f4 c\u1ef1c. Qua\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i\t Lorentz\t ng\u01b0\u1eddi\t ta\t c\u00f3\t th\u1ec3\t th\u1ea5y\t d\u1ec5\t d\u00e0ng\t r\u1eb1ng \u0111\u1ecbnh\tlu\u1eadt\ttruy\u1ec1n\t\u00e1nh\ts\u00e1ng\ttrong\tch\u00e2n\tkh\u00f4ng\t\u0111\u01b0\u1ee3c\tth\u1ecfa\tm\u00e3n\tcho v\u1eadt\tth\u1ec3\tquy\tchi\u1ebfu\tK\tc\u0169ng\tnh\u01b0\tcho\tv\u1eadt\tth\u1ec3\tquy\tchi\u1ebfu\tK\u2019\tqua\tth\u00ed\td\u1ee5 sau\t \u0111\u00e2y.\t M\u1ed9t\t t\u00edn\t hi\u1ec7u\t s\u00e1ng\t \u0111\u01b0\u1ee3c\t ph\u00e1t\t ra\t d\u1ecdc\t theo\t ph\u1ea7n\t tr\u1ee5c\t x d\u01b0\u01a1ng.\tN\u00f3\ts\u1ebd\t\u0111\u01b0\u1ee3c\ttruy\u1ec1n\t\u0111i\ttheo\tph\u01b0\u01a1ng\ttr\u00ecnh:","x\t=\tct ngh\u0129a\tl\u00e0\tv\u1edbi\tt\u1ed1c\t\u0111\u1ed9\tc.\tTheo\tc\u00e1c\tph\u01b0\u01a1ng\ttr\u00ecnh\tc\u1ee7a\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i Lorentz,\t quan\t h\u1ec7\t \u0111\u01a1n\t gi\u1ea3n\t n\u00e0y\t gi\u1eefa\t x\t v\u00e0\t t\t s\u1ebd\t k\u00e9o\t theo\t m\u1ed9t\t quan h\u1ec7\tgi\u1eefa\tx\t\u2019\tv\u00e0\tt\u2019.\tTh\u1ef1c\tv\u1eady,\tn\u1ebfu\tthay\tx\tb\u1eb1ng\ttr\u1ecb\ts\u1ed1\tct\ttrong\tph\u01b0\u01a1ng tr\u00ecnh\tth\u1ee9\tnh\u1ea5t\tv\u00e0\tth\u1ee9\tt\u01b0\tc\u1ee7a\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tLorentz\tth\u00ec\tta\ts\u1ebd\tc\u00f3: \t T\u1eeb\t\u0111\u00f3\tb\u1eb1ng\tm\u1ed9t\tph\u00e9p\tchia\tta\tc\u00f3\tngay: x\u2019\t=\tct\u2019 Ngh\u0129a\tl\u00e0\t\u00e1nh\ts\u00e1ng\t\u0111\u01b0\u1ee3c\ttruy\u1ec1n\ttheo\tph\u01b0\u01a1ng\ttr\u00ecnh\tn\u00e0y\ttr\u00ean\th\u1ec7 quy\t chi\u1ebfu\t K\u2019.\t Nh\u01b0\t v\u1eady,\t ch\u00fang\t ta\t \u0111\u00e3\t ch\u1ee9ng\t minh\t v\u1eadn\t t\u1ed1c\t truy\u1ec1n c\u1ee7a\t\u00e1nh\ts\u00e1ng\t\u0111\u1ed1i\tv\u1edbi\tv\u1eadt\tth\u1ec3\tquy\tchi\u1ebfu\tK\u2019\tc\u0169ng\tb\u1eb1ng\tc.\tT\u01b0\u01a1ng\tt\u1ef1 nh\u01b0\t th\u1ebf\t \u0111\u1ed1i\t v\u1edbi\t c\u00e1c\t tia\t s\u00e1ng\t truy\u1ec1n\t theo\t b\u1ea5t\t k\u1ef3\t chi\u1ec1u\t kh\u00e1c.\t D\u0129 nhi\u00ean\t\u0111i\u1ec1u\tn\u00e0y\tkh\u00f4ng\t\u0111\u00e1ng\tng\u1ea1c\tnhi\u00ean,\tb\u1edfi\tv\u00ec\tc\u00e1c\tph\u01b0\u01a1ng\ttr\u00ecnh c\u1ee7a\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tLorentz\t\u0111\u01b0\u1ee3c\tsuy\tra\tt\u1eeb\tquan\t\u0111i\u1ec3m\tn\u00e0y.","\u00a7\t12 V\u1eadn\tH\u00e0nh\tc\u1ee7a\tTh\u01b0\u1edbc\t\u0110o\tv\u00e0\t\u0110\u1ed3ng\tH\u1ed3\ttrong\tChuy\u1ec3n\t\u0110\u1ed9ng T\u00f4i\t \u0111\u1eb7t\t m\u1ed9t\t th\u01b0\u1edbc\t \u0111o\t m\u00e9t[32]\t v\u00e0o\t tr\u1ee5c-\t x\t \u2019\t c\u1ee7a\t K\t \u2019\t sao\t cho\t m\u1ed9t \u0111\u1ea7u\t (\u0111i\u1ec3m\t \u0111\u1ea7u)\t c\u1ee7a\t n\u00f3\t tr\u00f9ng\t v\u00e0o\t \u0111i\u1ec3m\t x\t \u2019\t =\t 0\t v\u00e0\t \u0111\u1ea7u\t kia\t (\u0111i\u1ec3m cu\u1ed1i)\tv\u00e0o\t\u0111i\u1ec3m\tx\u2019\t=\t1.\tC\u00e2u\th\u1ecfi:\tChi\u1ec1u\td\u00e0i\tc\u1ee7a\tth\u01b0\u1edbc\t\u0111o\tn\u00e0y\t\u0111\u1ed1i\tv\u1edbi K\tl\u00e0\tbao\tnhi\u00eau?\t\u0110\u1ec3\tbi\u1ebft\t\u0111i\u1ec1u\t\u0111\u00f3,\tch\u00fang\tta\tch\u1ec9\tc\u1ea7n\th\u1ecfi,\t\u0111i\u1ec3m\t\u0111\u1ea7u\tv\u00e0 \u0111i\u1ec3m\t cu\u1ed1i\t c\u1ee7a\t th\u01b0\u1edbc\t \u0111o\t n\u1eb1m\t \u1edf\t \u0111\u00e2u\t \u0111\u1ed1i\t v\u1edbi\t K\t t\u1ea1i\t m\u1ed9t\t th\u1eddi\t \u0111i\u1ec3m nh\u1ea5t\t \u0111\u1ecbnh\t t\t c\u1ee7a\t h\u1ec7\t th\u1ed1ng\t K.\t B\u1eb1ng\t ph\u01b0\u01a1ng\t tr\u00ecnh\t th\u1ee9\t nh\u1ea5t\t c\u1ee7a ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i\t Lorentz\t ng\u01b0\u1eddi\t ta\t t\u00ecm\t th\u1ea5y\t tr\u1ecb\t s\u1ed1\t c\u1ee7a\t hai\t \u0111i\u1ec3m\t n\u00e0y v\u00e0o\tth\u1eddi\t\u0111i\u1ec3m\tt\t=\t0 \t Kho\u1ea3ng\t c\u00e1ch\t c\u1ee7a\t hai\t \u0111i\u1ec3m\t do\t \u0111\u00f3\t l\u00e0\t .\t \u0110\u1ed1i\t v\u1edbi\t K, th\u01b0\u1edbc\t\u0111o\t\u0111ang\tchuy\u1ec3n\t\u0111\u1ed9ng\tv\u1edbi\tv\u1eadn\tt\u1ed1c\tl\u00e0\tv.\tDo\t\u0111\u00f3,\tchi\u1ec1u\td\u00e0i\tc\u1ee7a m\u1ed9t\tth\u01b0\u1edbc\t\u0111o\tm\u00e9t\tr\u1eafn\tchuy\u1ec3n\t\u0111\u1ed9ng\tv\u1edbi\tv\u1eadn\tt\u1ed1c\tv\td\u1ecdc\ttheo\tchi\u1ec1u d\u00e0i\tc\u1ee7a\tn\u00f3\tl\u00e0\tb\u1eb1ng\t \tc\u1ee7a\tm\u00e9t.\tDo\t\u0111\u00f3,\tth\u01b0\u1edbc\t\u0111o\tr\u1eafn\tkhi\t\u1edf tr\u1ea1ng\t th\u00e1i\t chuy\u1ec3n\t \u0111\u1ed9ng\t ng\u1eafn\t h\u01a1n\t khi\t n\u00f3\t \u1edf\t tr\u1ea1ng\t th\u00e1i\t \u0111\u1ee9ng\t y\u00ean, v\u00e0\t c\u00e0ng\t ng\u1eafn\t h\u01a1n,\t khi\t n\u00f3\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u00e0ng\t nhanh\t h\u01a1n.\t \u1ede\t v\u1eadn t\u1ed1c\t v\t =\t c\t th\u00ec\t .\t V\u1edbi\t v\u1eadn\t t\u1ed1c\t l\u1edbn\t h\u01a1n,\t c\u0103n\t s\u1ed1\t tr\u1edf th\u00e0nh\t\u1ea3o.\tT\u1eeb\t\u0111\u00f3\tch\u00fang\tta\tk\u1ebft\tlu\u1eadn\tr\u1eb1ng,\ttrong\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i, v\u1eadn\t t\u1ed1c\t c\t \u0111\u00f3ng\t vai\t tr\u00f2\t v\u1eadn\t t\u1ed1c\t gi\u1edbi\t h\u1ea1n.\t Kh\u00f4ng\t v\u1eadt\t th\u1ec3\t n\u00e0o\t \u0111\u1ea1t \u0111\u01b0\u1ee3c,\thay\tv\u01b0\u1ee3t\tqua\tn\u00f3\tc\u1ea3. 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N\u1ebfu\tng\u01b0\u1ee3c\tl\u1ea1i,\tch\u00fang\tta\tx\u00e9t\tm\u1ed9t\tth\u01b0\u1edbc\t\u0111o\tm\u00e9t\tn\u1eb1m\ttr\u00ean\ttr\u1ee5c\tx v\u00e0\t\u0111\u1ee9ng\ty\u00ean\t\u0111\u1ed1i\tv\u1edbi\tK,\tch\u00fang\tta\ts\u1ebd\tt\u00ecm\tth\u1ea5y\tk\u1ebft\tqu\u1ea3\tr\u1eb1ng,\tx\u00e9t\tt\u1eeb K\u2019\tn\u00f3\tc\u00f3\tchi\u1ec1u\td\u00e0i\tb\u1eb1ng\t \t c\u1ee7a\t m\u00e9t.\t \u0110i\u1ec1u\t n\u00e0y\t ho\u00e0n\t to\u00e0n ph\u00f9\th\u1ee3p\tv\u1edbi\ttinh\tth\u1ea7n\tc\u1ee7a\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i[33],\tc\u00e1i\t\u0111\u00e3\tl\u00e0m\tn\u1ec1n t\u1ea3ng\tc\u1ee7a\tsuy\tngh\u0129\tch\u00fang\tta. M\u1ed9t\t c\u00e1ch\t ti\u00ean\t nghi\u1ec7m,\t c\u00f3\t th\u1ec3\t th\u1ea5y\t d\u1ec5\t d\u00e0ng\t r\u1eb1ng,\t t\u1eeb\t c\u00e1c ph\u01b0\u01a1ng\t tr\u00ecnh\t c\u1ee7a\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i\t ch\u00fang\t ta\t ph\u1ea3i\t c\u00f3\t kh\u1ea3\t n\u0103ng\t bi\u1ebft \u0111\u01b0\u1ee3c\ts\u1ef1\tv\u1eadn\th\u00e0nh\tv\u1eadt\tl\u00fd\tc\u1ee7a\tc\u00e1c\tth\u01b0\u1edbc\t\u0111o\tv\u00e0\t\u0111\u1ed3ng\th\u1ed3.\tV\u00ec\tc\u00e1c\t\u0111\u1ea1i l\u01b0\u1ee3ng\t x,\t y,\t z,\t t\t kh\u00f4ng\t g\u00ec\t kh\u00e1c\t h\u01a1n\t l\u00e0\t nh\u1eefng\t k\u1ebft\t qu\u1ea3\t \u0111o\t \u0111\u1ea1c\t \u0111\u01b0\u1ee3c b\u1eb1ng\tth\u01b0\u1edbc\t\u0111o\tv\u00e0\t\u0111\u1ed3ng\th\u1ed3.\tN\u1ebfu\tl\u1ea5y\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tGalilei\tl\u00e0m\tn\u1ec1n t\u1ea3ng,\tch\u00fang\tta\ts\u1ebd\tkh\u00f4ng\tnh\u1eadn\t\u0111\u01b0\u1ee3c\tm\u1ed9t\ts\u1ef1\tr\u00fat\tng\u1eafn\tc\u1ee7a\tth\u01b0\u1edbc\t\u0111o chuy\u1ec3n\t\u0111\u1ed9ng. B\u00e2y\tgi\u1edd\tch\u00fang\tta\tx\u00e9t\tm\u1ed9t\t\u0111\u1ed3ng\th\u1ed3\tv\u1edbi\t\u0111\u01a1n\tv\u1ecb\tl\u00e0\tgi\u00e2y,\tlu\u00f4n\tn\u1eb1m t\u1ea1i\t\u0111i\u1ec3m\tg\u1ed1c\t(x\t\u2019\t=\t0)\tc\u1ee7a\tK',\tt'\t=\t0\tv\u00e0\tt\u2019\t=\t1\tl\u00e0\thai\tti\u1ebfng\tt\u00edch\tli\u00ean\tti\u1ebfp c\u1ee7a\t \u0111\u1ed3ng\t h\u1ed3\t n\u00e0y.\t Ph\u01b0\u01a1ng\t tr\u00ecnh\t th\u1ee9\t nh\u1ea5t\t v\u00e0\t th\u1ee9\t hai\t c\u1ee7a\t ph\u00e9p bi\u1ebfn\t\u0111\u1ed5i\tLorentz\tcho\tk\u1ebft\tqu\u1ea3 t\t=\t0 v\u00e0 Quan\t s\u00e1t\t t\u1eeb\t K,\t \u0111\u1ed3ng\t h\u1ed3\t chuy\u1ec3n\t \u0111\u1ed9ng\t v\u1edbi\t v\u1eadn\t t\u1ed1c\t v;\t x\u00e9t\t t\u1eeb\t v\u1eadt th\u1ec3\tquy\tchi\u1ebfu\tn\u00e0y,\tkho\u1ea3ng\tc\u00e1ch\tgi\u1eefa\thai\tti\u1ebfng\tt\u00edch\tkh\u00f4ng\tph\u1ea3i\tl\u00e0 1\tgi\u00e2y\tn\u1eefa,\tm\u00e0\tl\u00e0 \tgi\u00e2y, ngh\u0129a\tl\u00e0\tm\u1ed9t\tth\u1eddi\tgian\tl\u1edbn\th\u01a1n.\tNh\u01b0\tm\u1ed9t\th\u1ec7\tqu\u1ea3\tchuy\u1ec3n\t\u0111\u1ed9ng c\u1ee7a\t n\u00f3,\t \u0111\u1ed3ng\t h\u1ed3\t ch\u1ea1y\t ch\u1eadm\t h\u01a1n\t l\u00e0\t khi\t n\u00f3\t \u0111\u1ee9ng\t y\u00ean.\t \u1ede\t \u0111\u00e2y,\t v\u1eadn","t\u1ed1c\tc\t c\u0169ng\t \u0111\u00f3ng\t vai\t tr\u00f2\t c\u1ee7a\t m\u1ed9t\t v\u1eadn\t t\u1ed1c\t gi\u1edbi\t h\u1ea1n\t kh\u00f4ng\t th\u1ec3\t \u0111\u1ea1t t\u1edbi\t\u0111\u01b0\u1ee3c.","\u00a7\t13 \u0110\u1ecbnh\tL\u00fd\tC\u1ed9ng\tV\u1eadn\tT\u1ed1c\t-\tTh\u00ed\tNghi\u1ec7m\tFizeau V\u00ec\ttrong\tth\u1ef1c\tt\u1ebf\tch\u00fang\tta\tch\u1ec9\tdi\tchuy\u1ec3n\t\u0111\u01b0\u1ee3c\t\u0111\u1ed3ng\th\u1ed3\tv\u00e0\tth\u01b0\u1edbc \u0111o\t v\u1edbi\t v\u1eadn\t t\u1ed1c\t nh\u1ecf\t so\t v\u1edbi\t c,\t cho\t n\u00ean\t nh\u1eefng\t k\u1ebft\t qu\u1ea3\t c\u1ee7a\t Ch\u01b0\u01a1ng tr\u01b0\u1edbc\th\u1ea7u\tnh\u01b0\tkh\u00f4ng\tth\u1ec3\t\u0111em\tso\ts\u00e1nh\t\u0111\u01b0\u1ee3c\ttr\u1ef1c\tti\u1ebfp\tv\u1edbi\tth\u1ef1c\tt\u1ebf\t. M\u1eb7t\tkh\u00e1c,\tnh\u1eefng\tk\u1ebft\tqu\u1ea3\t\u0111\u00f3\tt\u1ecf\tra\tl\u1ea1\tm\u1eaft\t\u0111\u1ed1i\tv\u1edbi\t\u0111\u1ed9c\tgi\u1ea3,\tn\u00ean\tv\u00ec\tl\u1ebd \u0111\u00f3\tb\u00e2y\tgi\u1edd\tt\u00f4i\ts\u1ebd\tr\u00fat\tra\tm\u1ed9t\th\u1ec7\tlu\u1eadn\tkh\u00e1c\tt\u1eeb\tl\u00fd\tthuy\u1ebft,\t\u0111i\u1ec1u\tc\u00f3\tth\u1ec3 \u0111\u01b0\u1ee3c\t suy\t ra\t d\u1ec5\t d\u00e0ng\t t\u1eeb\t nh\u1eefng\t g\u00ec\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t tr\u00ecnh\t b\u00e0y\t \u0111\u1ebfn\t nay, nh\u01b0ng\tn\u00f3\ts\u1ebd\t\u0111\u01b0\u1ee3c\tki\u1ec3m\tch\u1ee9ng\tm\u1ed9t\tc\u00e1ch\tr\u1ef1c\tr\u1ee1\tt\u1eeb\tth\u00ed\tnghi\u1ec7m. Trong\t \u00a7\t 6,\t ch\u00fang\t ta\t \u0111\u00e3\t suy\t ra\t \u0111\u1ecbnh\t l\u00fd\t c\u1ed9ng\t cho\t c\u00e1c\t v\u1eadn\t t\u1ed1c c\u00f9ng\t chi\u1ec1u,\t nh\u01b0\t h\u1ec7\t lu\u1eadn\t t\u1eeb\t c\u00e1c\t gi\u1ea3\t thuy\u1ebft\t c\u1ee7a\t c\u01a1\t h\u1ecdc\t c\u1ed5\t \u0111i\u1ec3n. C\u00f9ng\t k\u1ebft\t qu\u1ea3\t \u0111\u00f3\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t suy\t ra\t d\u1ec5\t d\u00e0ng\t t\u1eeb\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i Galilei\t (\u00a711).\t Th\u1ef1c\t v\u1eady,\t thay\t v\u00ec\t m\u1ed9t\t ng\u01b0\u1eddi\t \u0111i\t trong\t xe,\t ch\u00fang\t ta x\u00e9t\t m\u1ed9t\t \u0111i\u1ec3m,\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u1ed1i\t v\u1edbi\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t K'\t theo\t ph\u01b0\u01a1ng tr\u00ecnh x\u2019\t=\twt\u2019 T\u1eeb\t ph\u01b0\u01a1ng\t tr\u00ecnh\t th\u1ee9\t nh\u1ea5t\t v\u00e0\t th\u1ee9\t t\u01b0\t c\u1ee7a\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i\t Galilei ng\u01b0\u1eddi\tta\tc\u00f3\tth\u1ec3\tdi\u1ec5n\tt\u1ea3\tx\u2019\tv\u00e0\tt\u2019\ttheo\tx\tv\u00e0\tt,\tt\u1eeb\t\u0111\u00f3\tch\u00fang\tta\t\u0111\u01b0\u1ee3c\tk\u1ebft qu\u1ea3 x\t=\t(v\t+\tw)t Ph\u01b0\u01a1ng\ttr\u00ecnh\tn\u00e0y\tdi\u1ec5n\tt\u1ea3\tkh\u00f4ng\tg\u00ec\tkh\u00e1c\th\u01a1n\t\u0111\u1ecbnh\tlu\u1eadt\tchuy\u1ec3n \u0111\u1ed9ng\t c\u1ee7a\t \u0111i\u1ec3m\t ch\u00fang\t ta\t x\u00e9t\t \u0111\u1ed1i\t v\u1edbi\t h\u1ec7\t th\u1ed1ng\t K\t (ng\u01b0\u1eddi\t \u0111i\t b\u1ed9\t \u0111\u1ed1i v\u1edbi\t n\u1ec1n\t ray)\t m\u00e0\t v\u1eadn\t t\u1ed1c\t ch\u00fang\t ta\t g\u1ecdi\t l\u00e0\t W.\t Cho\t n\u00ean\t gi\u1ed1ng\t nh\u01b0 trong\t\u00a7\t6,\tch\u00fang\tta\t\u0111\u01b0\u1ee3c W\t=\tv\t+\tw\t(A) Nh\u01b0ng\t ch\u00fang\t ta\t c\u0169ng\t ho\u00e0n\t to\u00e0n\t c\u00f3\t kh\u1ea3\t n\u0103ng\t th\u1ef1c\t hi\u1ec7n\t c\u00e1ch suy\tngh\u0129\tn\u00e0y\ttr\u00ean\tc\u01a1\ts\u1edf\tc\u1ee7a\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i. Trong\tph\u01b0\u01a1ng\ttr\u00ecnh x\u2019\t-\twt\u2019 ng\u01b0\u1eddi\t ta\t ch\u1ec9\t c\u1ea7n\t di\u1ec5n\t t\u1ea3\t x\u2019\t v\u00e0\t t'\t theo\t x\t v\u00e0\t t\t b\u1eb1ng\t c\u00e1ch\t s\u1eed\t d\u1ee5ng ph\u01b0\u01a1ng\ttr\u00ecnh\tth\u1ee9\tnh\u1ea5t\tv\u00e0\tth\u1ee9\tt\u01b0\tc\u1ee7a\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tLorentz.\tThay v\u00ec\tph\u01b0\u01a1ng\ttr\u00ecnh\t(A),\tng\u01b0\u1eddi\tta\ts\u1ebd\t\u0111\u01b0\u1ee3c\tph\u01b0\u01a1ng\ttr\u00ecnh\t(B):","t\u01b0\u01a1ng\t \u1ee9ng\t v\u1edbi\t \u0111\u1ecbnh\t l\u00fd\t c\u1ed9ng\t cho\t c\u00e1c\t v\u1eadn\t t\u1ed1c\t c\u00f9ng\t chi\u1ec1u\t trong tr\u01b0\u1eddng\th\u1ee3p\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i.\tC\u00e2u\th\u1ecfi\tb\u00e2y\tgi\u1edd\tl\u00e0,\tc\u00e1i\tn\u00e0o\ttrong\thai \u0111\u1ecbnh\tl\u00fd\t\u0111\u00f3\t\u0111\u1ee9ng\tv\u1eefng\ttr\u01b0\u1edbc\tkinh\tnghi\u1ec7m\tth\u1ef1c\tti\u1ec5n.\tV\u1ec1\t\u0111i\u1ec1u\tn\u00e0y, m\u1ed9t\t th\u00ed\t nghi\u1ec7m\t c\u1ef1c\t k\u1ef3\t quan\t tr\u1ecdng\t s\u1ebd\t ch\u1ec9\t cho\t ch\u00fang\t ta\t bi\u1ebft,\t th\u00ed nghi\u1ec7m\tm\u00e0\tnh\u00e0\tv\u1eadt\tl\u00fd\tthi\u00ean\tt\u00e0i\tFizeau\t\u0111\u00e3\tth\u1ef1c\thi\u1ec7n\th\u01a1n\tn\u1eeda\tth\u1ebf k\u1ef7\t tr\u01b0\u1edbc,\t v\u00e0\t t\u1eeb\t \u0111\u00f3\t \u0111\u1ebfn\t nay\t v\u00e0i\t ng\u01b0\u1eddi\t trong\t s\u1ed1\t nh\u1eefng\t nh\u00e0\t v\u1eadt\t l\u00fd h\u1ecdc\t th\u1ef1c\t nghi\u1ec7m\t t\u00e0i\t gi\u1ecfi\t nh\u1ea5t\t l\u1eb7p\t l\u1ea1i,\t cho\t n\u00ean\t k\u1ebft\t qu\u1ea3\t c\u1ee7a\t n\u00f3 kh\u00f4ng\t th\u1ec3\t nghi\t ng\u1edd\t \u0111\u01b0\u1ee3c.\t Th\u00ed\t nghi\u1ec7m\t nh\u1eafm\t \u0111\u1ebfn\t b\u00e0i\t to\u00e1n\t sau \u0111\u00e2y.\tTrong\tm\u1ed9t\tch\u1ea5t\tl\u1ecfng\t\u0111\u1ee9ng\ty\u00ean,\t\u00e1nh\ts\u00e1ng\ttruy\u1ec1n\t\u0111i\tv\u1edbi\tm\u1ed9t v\u1eadn\t t\u1ed1c\t nh\u1ea5t\t \u0111\u1ecbnh\t l\u00e0\t w.\t C\u00e2u\t h\u1ecfi\t \u0111\u1eb7t\t ra:\t \u00c1nh\t s\u00e1ng\t s\u1ebd\t truy\u1ec1n\t v\u1edbi v\u1eadn\tt\u1ed1c\tn\u00e0o\ttrong\t\u1ed1ng\tnghi\u1ec7m\ttheo\tchi\u1ec1u\tm\u0169i\tt\u00ean\ttrong\th\u00ecnh\tv\u1ebd, n\u1ebfu\tch\u1ea5t\tl\u1ecfng\tn\u00f3i\ttr\u00ean\tch\u1ea3y\ttrong\t\u1ed1ng\tnghi\u1ec7m\tv\u1edbi\tv\u1eadn\tt\u1ed1c\tv. Th\u1ec3\t theo\t tinh\t th\u1ea7n\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i,\t ch\u00fang\t ta\t nh\u1ea5t\t thi\u1ebft ph\u1ea3i\tgi\u1ea3\tthi\u1ebft\tr\u1eb1ng,\t\u0111\u1ed1i\tv\u1edbi\tch\u1ea5t\tl\u1ecfng,\t\u00e1nh\ts\u00e1ng\t lu\u00f4n\tlu\u00f4n\t truy\u1ec1n v\u1edbi\t c\u00f9ng\t v\u1eadn\t t\u1ed1c\t w,\t d\u00f9\t ch\u1ea5t\t l\u1ecfng\t c\u00f3\t chuy\u1ec3n\t \u0111\u1ed9ng\t hay\t \u0111\u1ee9ng\t y\u00ean \u0111\u1ed1i\t v\u1edbi\t c\u00e1c\t v\u1eadt\t th\u1ec3\t kh\u00e1c.\t Nh\u01b0\t v\u1eady,\t v\u1eadn\t t\u1ed1c\t truy\u1ec1n\t c\u1ee7a\t \u00e1nh\t s\u00e1ng \u0111\u1ed1i\tv\u1edbi\tch\u1ea5t\tl\u1ecfng,\tv\u00e0\tv\u1eadn\tt\u1ed1c\tc\u1ee7a\tch\u1ea5t\tl\u1ecfng\t\u0111\u1ed1i\tv\u1edbi\t\u1ed1ng\tnghi\u1ec7m,\tc\u1ea3 hai\t \u0111\u01b0\u1ee3c\t bi\u1ebft\t tr\u01b0\u1edbc;\t v\u1ea5n\t \u0111\u1ec1\t l\u00e0\t t\u00ecm\t v\u1eadn\t t\u1ed1c\t \u00e1nh\t s\u00e1ng\t \u0111\u1ed1i\t v\u1edbi\t \u1ed1ng nghi\u1ec7m. 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Tuy\t nhi\u00ean,\t b\u00e2y\t gi\u1edd\t ch\u00fang\t ta\t c\u0169ng\t c\u1ea7n\t n\u00eau\t l\u00ean\t r\u1eb1ng,\t m\u1ed9t\t th\u1eddi gian\t d\u00e0i\t tr\u01b0\u1edbc\t khi\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t \u0111\u01b0\u1ee3c\t thi\u1ebft\t l\u1eadp\t \u0111\u00e3\t c\u00f3\t m\u1ed9t\t l\u00fd thuy\u1ebft\t v\u1ec1\t hi\u1ec7n\t t\u01b0\u1ee3ng\t n\u00e0y\t c\u1ee7a\t H.A.\t Lorentz,\t b\u1eb1ng\t con\t \u0111\u01b0\u1eddng thu\u1ea7n\t t\u00fay\t \u0111\u1ed9ng\t \u0111i\u1ec7n\t h\u1ecdc,\t v\u00e0\t d\u01b0\u1edbi\t s\u1ef1\t s\u1eed\t d\u1ee5ng\t nh\u1eefng\t gi\u1ea3\t thuy\u1ebft nh\u1ea5t\t \u0111\u1ecbnh\t v\u1ec1\t c\u1ea5u\t tr\u00fac\t \u0111i\u1ec7n\t t\u1eeb\t c\u1ee7a\t v\u1eadt\t ch\u1ea5t.\t T\u00ecnh\t hu\u1ed1ng\t n\u00e0y\t tuy nhi\u00ean\tkh\u00f4ng\th\u1ec1\tl\u00e0m\tgi\u1ea3m\t\u0111i\ts\u1ee9c\tthuy\u1ebft\tph\u1ee5c\tc\u1ee7a\tth\u00ed\tnghi\u1ec7m\tnh\u01b0 m\u1ed9t\tph\u00e9p\tth\u1eed\tquy\u1ebft\t\u0111\u1ecbnh\tc\u00f3\tl\u1ee3i\tcho\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i.\tB\u1edfi\tv\u00ec\t\u0111\u1ed9ng \u0111i\u1ec7n\t h\u1ecdc\t c\u1ee7a\t Maxwell-Lorentz\t m\u00e0\t l\u00fd\t thuy\u1ebft\t ban\t \u0111\u1ea7u\t d\u1ef1a\t v\u00e0o, kh\u00f4ng\th\u1ec1\t\u0111\u1ed1i\tkh\u00e1ng\tv\u1edbi\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i.\t\u0110\u00fang\th\u01a1n,\tthuy\u1ebft\tsau \u0111\u00e3\t \u0111\u01b0\u1ee3c\t ph\u00e1t\t tri\u1ec3n\t t\u1eeb\t \u0111i\u1ec7n\t \u0111\u1ed9ng\t h\u1ecdc\t nh\u01b0\t s\u1ef1\t t\u1ed5ng\t h\u1ee3p\t \u0111\u01a1n\t gi\u1ea3n m\u1ed9t\t c\u00e1ch\t ng\u1ea1c\t nhi\u00ean\t v\u00e0\t kh\u00e1i\t qu\u00e1t\t h\u00f3a\t c\u1ee7a\t c\u00e1c\t gi\u1ea3\t thuy\u1ebft\t tr\u01b0\u1edbc \u0111\u00e2y\t\u0111\u1ed9c\tl\u1eadp\tnhau\tm\u00e0\ttr\u00ean\t\u0111\u00f3\t\u0111i\u1ec7n\t\u0111\u1ed9ng\th\u1ecdc\t\u0111\u00e3\t\u0111\u01b0\u1ee3c\tx\u00e2y\td\u1ef1ng.","\u00a7\t14 Gi\u00e1\tTr\u1ecb\tH\u1ed7\tTr\u1ee3\tPh\u00e1t\tMinh\tc\u1ee7a\tThuy\u1ebft\tT\u01b0\u01a1ng\t\u0110\u1ed1i D\u00f2ng\t \u00fd\t t\u01b0\u1edfng\t \u0111\u1ebfn\t nay\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t t\u00f3m\t t\u1eaft\t l\u1ea1i\t nh\u01b0\t sau:\t Kinh nghi\u1ec7m\t \u0111\u00e3\t \u0111\u01b0a\t \u0111\u1ebfn\t ni\u1ec1m\t tin\t r\u1eb1ng\t m\u1ed9t\t m\u1eb7t\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i (theo\t ngh\u0129a\t h\u1eb9p)\t l\u00e0\t \u0111\u00fang,\t v\u00e0\t m\u1eb7t\t kh\u00e1c\t v\u1eadn\t t\u1ed1c\t truy\u1ec1n\t c\u1ee7a\t \u00e1nh s\u00e1ng\t trong\t ch\u00e2n\t kh\u00f4ng\t \u0111\u01b0\u1ee3c\t xem\t l\u00e0\t m\u1ed9t\t h\u1eb1ng\t s\u1ed1\t c.\t B\u1eb1ng\t c\u00e1ch h\u1ee3p\tnh\u1ea5t\thai\tti\u1ec1n\t\u0111\u1ec1\tn\u00e0y\tl\u1ea1i,\tch\u00fang\tta\t\u0111\u1ea1t\t\u0111\u01b0\u1ee3c\t\u0111\u1ecbnh\tlu\u1eadt\tbi\u1ebfn\t\u0111\u1ed5i cho\tc\u00e1c\tt\u1ecda\t\u0111\u1ed9\tth\u1eb3ng\tg\u00f3c\tx,\ty,\tz\tv\u00e0\tth\u1eddi\tgian\tt\tc\u1ee7a\tc\u00e1c\ts\u1ef1\tki\u1ec7n\tc\u1ea5u th\u00e0nh\tc\u00e1c\thi\u1ec7n\tt\u01b0\u1ee3ng\tt\u1ef1\tnhi\u00ean.\tV\u00e0\ttrong\tkhu\u00f4n\tkh\u1ed5\tn\u00e0y,\tth\u1ef1c\tt\u1ebf ch\u00fang\t ta\t \u0111\u00e3\t \u0111\u1ea1t\t \u0111\u01b0\u1ee3c\t kh\u00f4ng\t ph\u1ea3i\t ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i\t Galilei,\t m\u00e0\t kh\u00e1c v\u1edbi\tc\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n,\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tLorentz. 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C\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n\tc\u1ea7n\tm\u1ed9t\ts\u1ef1\ttu\tch\u1ec9nh\t\u0111\u1ec3\tph\u00f9\th\u1ee3p\tv\u1edbi\t\u0111\u00f2i\th\u1ecfi\tc\u1ee7a thuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p.\tTuy\tnhi\u00ean\tph\u1ea7n\tch\u00ednh\tc\u1ee7a\ts\u1ef1\ttu\tch\u1ec9nh\tn\u00e0y ch\u1ec9\t li\u00ean\t quan\t ch\u1ee7\t y\u1ebfu\t \u0111\u1ebfn\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t cho\t c\u00e1c\t chuy\u1ec3n\t \u0111\u1ed9ng nhanh,\t\u1edf\t\u0111\u00f3\tv\u1eadn\tt\u1ed1c\tv\tc\u1ee7a\tv\u1eadt\tch\u1ea5t\tkh\u00f4ng\tqu\u00e1\tnh\u1ecf\t\u0111\u1ed1i\tv\u1edbi\tv\u1eadn\tt\u1ed1c \u00e1nh\t s\u00e1ng.\t Kinh\t nghi\u1ec7m\t cho\t ta\t bi\u1ebft\t chuy\u1ec3n\t \u0111\u1ed9ng\t nhanh\t nh\u01b0\t th\u1ebf ch\u1ec9\t x\u1ea3y\t ra\t \u1edf\t electron\t v\u00e0\t ion;\t \u1edf\t nh\u1eefng\t chuy\u1ec3n\t \u0111\u1ed9ng\t kh\u00e1c,\t s\u1ef1 ch\u00eanh\t l\u1ec7ch\t so\t v\u1edbi\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t c\u01a1\t h\u1ecdc\t c\u1ed5\t \u0111i\u1ec3n\t l\u00e0\t qu\u00e1\t nh\u1ecf\t \u0111\u1ec3\t c\u00f3 th\u1ec3\tth\u1ea5y\t\u0111\u01b0\u1ee3c\ttrong\tth\u00ed\tnghi\u1ec7m.\tv\u1ec1\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tsao,\tch\u00fang ta\ts\u1ebd\tn\u00f3i\t\u0111\u1ebfn\tkhi\tb\u00e0n\tv\u1ec1\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tr\u1ed9ng. Theo\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i,\t \u0111\u1ed9ng\t n\u0103ng\t c\u1ee7a\t m\u1ed9t\t \u0111i\u1ec3m\t v\u1eadt\t ch\u1ea5t\t c\u00f3 kh\u1ed1i\tl\u01b0\u1ee3ng\tm\t kh\u00f4ng\t c\u00f2n\t \u0111\u01b0\u1ee3c\t x\u00e1c\t \u0111\u1ecbnh\t n\u1eefa\t b\u1edfi\t bi\u1ec3u\t th\u1ee9c\t quen thu\u1ed9c m\u00e0\tb\u1eb1ng\tbi\u1ec3u\tth\u1ee9c Bi\u1ec3u\t th\u1ee9c\t n\u00e0y\t s\u1ebd\t tr\u1edf\t th\u00e0nh\t v\u00f4\t c\u1ef1c\t khi\t v\u1eadn\t t\u1ed1c\t v\t ti\u1ebfn\t g\u1ea7n\t \u0111\u1ebfn v\u1eadn\tt\u1ed1c\t\u00e1nh\ts\u00e1ng\tc.\tV\u1eadn\tt\u1ed1c\tdo\t\u0111\u00f3\tph\u1ea3i\tlu\u00f4n\tnh\u1ecf\th\u01a1n\tc,\td\u00f9\tng\u01b0\u1eddi ta\tc\u00f3\ts\u1eed\td\u1ee5ng\tbao\tnhi\u00eau\tn\u0103ng\tl\u01b0\u1ee3ng\t\u0111i\tn\u1eefa\tcho\tvi\u1ec7c\tt\u0103ng\tt\u1ed1c.\tN\u1ebfu tri\u1ec3n\t khai\t bi\u1ec3u\t th\u1ee9c\t n\u00e0y\t c\u1ee7a\t \u0111\u1ed9ng\t n\u0103ng\t th\u00e0nh\t chu\u1ed7i,\t ch\u00fang\t ta","c\u00f3: [39] S\u1ed1\th\u1ea1ng\tth\u1ee9\tba\ttrong\tchu\u1ed7i\tn\u00e0y\tlu\u00f4n\tlu\u00f4n\tnh\u1ecf\t\u0111\u1ed1i\tv\u1edbi\ts\u1ed1\th\u1ea1ng th\u1ee9\thai,\tl\u00e0\ts\u1ed1\th\u1ea1ng\tduy\tnh\u1ea5t\t\u0111\u01b0\u1ee3c\t\u0111\u1ec3\t\u00fd\t\u0111\u1ebfn\ttrong\tc\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n, khi\tv\t2\t\/c\t2\tnh\u1ecf\t\u0111\u1ed1i\tv\u1edbi\t1.\tS\u1ed1\th\u1ea1ng\tth\u1ee9\tnh\u1ea5t\tmc\t2\tkh\u00f4ng\tch\u1ee9a\tv\u1eadn t\u1ed1c,\t do\t \u0111\u00f3\t kh\u00f4ng\t c\u1ea7n\t thi\u1ebft\t \u0111\u01b0\u1ee3c\t \u0111\u1ec3\t \u00fd\t khi\t ng\u01b0\u1eddi\t ta\t ch\u1ec9\t quan\t t\u00e2m [\u0111\u1ebfn]\t n\u0103ng\t l\u01b0\u1ee3ng\t c\u1ee7a\t m\u1ed9t\t \u0111i\u1ec3m\t kh\u1ed1i\t l\u01b0\u1ee3ng[40]\t l\u1ec7\t thu\u1ed9c\t th\u1ebf\t n\u00e0o v\u00e0o\t v\u1eadn\t t\u1ed1c.\t V\u1ec1\t t\u1ea7m\t quan\t tr\u1ecdng\t c\u01a1\t b\u1ea3n\t c\u1ee7a\t n\u00f3\t ch\u00fang\t ta\t s\u1ebd\t n\u00f3i \u0111\u1ebfn\tsau. K\u1ebft\t qu\u1ea3\t quan\t tr\u1ecdng\t nh\u1ea5t\t c\u00f3\t t\u00ednh\t ch\u1ea5t\t kh\u00e1i\t qu\u00e1t\t m\u00e0\t thuy\u1ebft t\u01b0\u01a1ng\t \u0111\u1ed1i\t \u0111\u00e3\t \u0111em\t l\u1ea1i\t l\u00e0\t v\u1ec1\t kh\u00e1i\t ni\u1ec7m\t kh\u1ed1i\t l\u01b0\u1ee3ng.\t V\u1eadt\t l\u00fd\t ti\u1ec1n- t\u01b0\u01a1ng-\u0111\u1ed1i\t bi\u1ebft\t \u0111\u1ebfn\t hai\t \u0111\u1ecbnh\t l\u00fd\t b\u1ea3o\t to\u00e0n\t c\u00f3\t \u00fd\t ngh\u0129a\t c\u01a1\t b\u1ea3n,\t \u0111\u00f3\t l\u00e0 \u0111\u1ecbnh\tlu\u1eadt\tb\u1ea3o\tto\u00e0n\tn\u0103ng\tl\u01b0\u1ee3ng\tv\u00e0\t\u0111\u1ecbnh\tlu\u1eadt\tb\u1ea3o\tto\u00e0n\tkh\u1ed1i\tl\u01b0\u1ee3ng; hai\t \u0111\u1ecbnh\t lu\u1eadt\t c\u01a1\t b\u1ea3n\t n\u00e0y\t \u0111\u01b0\u1ee3c\t bi\u1ebft\t nh\u01b0\t ho\u00e0n\t to\u00e0n\t \u0111\u1ed9c\t l\u1eadp\t v\u1edbi nhau.\t Nh\u01b0ng\t v\u1edbi\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i,\t c\u1ea3\t hai\t h\u00f2a\t nh\u1eadp\t l\u1ea1i\t th\u00e0nh m\u1ed9t\t \u0111\u1ecbnh\t lu\u1eadt.\t \u0110i\u1ec1u\t n\u00e0y\t h\u00ecnh\t th\u00e0nh\t ra\t sao,\t v\u00e0\t s\u1ef1\t h\u00f2a\t nh\u1eadp\t l\u1ea1i \u0111\u01b0\u1ee3c\thi\u1ec3u\tth\u1ebf\tn\u00e0o,\tch\u00fang\tta\ts\u1ebd\ttr\u00ecnh\tb\u00e0y\tt\u00f3m\tt\u1eaft\tsau\t\u0111\u00e2y. Nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t \u0111\u00f2i\t h\u1ecfi\t \u0111\u1ecbnh\t lu\u1eadt\t b\u1ea3o\t to\u00e0n\t n\u0103ng\t l\u01b0\u1ee3ng kh\u00f4ng\tnh\u1eefng\t\u0111\u00fang\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tK\tm\u00e0\t\u0111\u1ed1i\tv\u1edbi\tc\u1ea3\tm\u1ed7i\th\u1ec7 t\u1ecda\t\u0111\u1ed9\tK\u2019\t\u1edf\ttrong\ttr\u1ea1ng\tth\u00e1i\tchuy\u1ec3n\t\u0111\u1ed9ng\tt\u1ecbnh\tti\u1ebfn\t\u0111\u1ec1u\t\u0111\u1ed1i\tv\u1edbi\tK, t\u00f3m\t l\u1ea1i,\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed7i\t h\u1ec7\t t\u1ecda\t \u0111\u1ed9\t Galilei.\t Trong\t s\u1ef1\t chuy\u1ec3n\t ti\u1ebfp\t gi\u1eefa hai\th\u1ec7\tnh\u01b0\tth\u1ebf\tth\u00ec\tkh\u00e1c\tv\u1edbi\tc\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n,\tph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tLorentz l\u00e0\ty\u1ebfu\tt\u1ed1\tquy\u1ebft\t\u0111\u1ecbnh. 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c\u1eadp\t khi\t b\u00e0n\t v\u1ec1\t th\u00ed\t nghi\u1ec7m\t c\u01a1\t b\u1ea3n\t c\u1ee7a\t Fizeau.\t Thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i h\u1eb9p\t \u0111\u01b0\u1ee3c\t k\u1ebft\t tinh\t t\u1eeb\t thuy\u1ebft\t Maxwell-Lorentz\t v\u1ec1\t c\u00e1c\t hi\u1ec7n\t t\u01b0\u1ee3ng \u0111i\u1ec7n\tt\u1eeb.\tCho\tn\u00ean\tt\u1ea5t\tc\u1ea3\td\u1eef\tki\u1ec7n\tth\u1ef1c\tnghi\u1ec7m\th\u1ed7\ttr\u1ee3\tthuy\u1ebft\t\u0111i\u1ec7n\tt\u1eeb c\u0169ng\t\u0111\u1ec1u\th\u1ed7\ttr\u1ee3\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i.\tT\u00f4i\tmu\u1ed1n\tnh\u1eafc\t\u1edf\t\u0111\u00e2y\tm\u1ed9t\t\u0111i\u1ec1u \u0111\u1eb7c\t bi\u1ec7t\t quan\t tr\u1ecdng\t l\u00e0\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t cho\t ph\u00e9p\t ch\u00fang\t ta\t suy di\u1ec5n\t\u0111\u01b0\u1ee3c\tnh\u1eefng\t\u1ea3nh\th\u01b0\u1edfng\tl\u00ean\t\u00e1nh\ts\u00e1ng\t\u0111i\t\u0111\u1ebfn\tch\u00fang\tta\tt\u1eeb\tc\u00e1c v\u00ec\t sao\t c\u1ed1\t \u0111\u1ecbnh\t g\u00e2y\t ra\t do\t chuy\u1ec3n\t \u0111\u1ed9ng\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t c\u1ee7a\t tr\u00e1i\t \u0111\u1ea5t\t \u0111\u1ed1i v\u1edbi\t c\u00e1c\t v\u00ec\t sao\t c\u1ed1\t \u0111\u1ecbnh\t kia.\t C\u00e1c\t \u1ea3nh\t h\u01b0\u1edfng\t n\u00e0y\t \u0111\u01b0\u1ee3c\t suy\t ra\t m\u1ed9t c\u00e1ch\tv\u00f4\tc\u00f9ng\t\u0111\u01a1n\tgi\u1ea3n,\tv\u00e0\tph\u00f9\th\u1ee3p\tv\u1edbi\tkinh\tnghi\u1ec7m\tth\u1ef1c\tti\u1ec5n.\t\u0110\u00f3 l\u00e0\ts\u1ef1\tdi\tchuy\u1ec3n\th\u1eb1ng\tn\u0103m\tv\u1ecb\ttr\u00ed\t\u1ea3o\tc\u1ee7a\tc\u00e1c\tv\u00ec\tsao\tc\u1ed1\t\u0111\u1ecbnh\tnh\u01b0\th\u1ec7 qu\u1ea3\t c\u1ee7a\t s\u1ef1\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t qu\u1ea3\t \u0111\u1ea5t\t xung\t quanh\t m\u1eb7t\t tr\u1eddi\t (hi\u1ec7n t\u01b0\u1ee3ng\t quang\t sai[43]),\t v\u00e0\t \u00e1nh\t h\u01b0\u1edfng\t c\u1ee7a\t c\u00e1c\t th\u00e0nh\t ph\u1ea7n\t h\u01b0\u1edbng t\u00e2m\tc\u1ee7a\tc\u00e1c\tchuy\u1ec3n\t\u0111\u1ed9ng\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tc\u1ee7a\tc\u00e1c\tv\u00ec\tsao\tc\u1ed1\t\u0111\u1ecbnh\t\u0111\u1ed1i\tv\u1edbi tr\u00e1i\t\u0111\u1ea5t\tl\u00ean\tm\u00e0u\ts\u1eafc\tc\u1ee7a\t\u00e1nh\ts\u00e1ng\tph\u00e1t\tra\tt\u1eeb\tch\u00fang\t\u0111i\t\u0111\u1ebfn\tch\u00fang ta.\t \u1ea2nh\t h\u01b0\u1edfng\t sau\t \u0111\u01b0\u1ee3c\t th\u1ec3\t hi\u1ec7n\t b\u1eb1ng\t m\u1ed9t\t s\u1ef1\t d\u1ecbch\t chuy\u1ec3n\t nh\u1ecf c\u1ee7a\t c\u00e1c\t v\u1ea1ch\t quang\t ph\u1ed5\t c\u1ee7a\t \u00e1nh\t s\u00e1ng\t truy\u1ec1n\t \u0111\u1ebfn\t ch\u00fang\t ta\t t\u1eeb m\u1ed9t\tv\u00ec\tsao\tc\u1ed1\t\u0111\u1ecbnh,\tkhi\tso\ts\u00e1nh\tv\u1edbi\tv\u1ecb\ttr\u00ed\tc\u1ee7a\tc\u00f9ng\tc\u00e1c\tv\u1ea1ch\tquang ph\u1ed5\t\u0111\u01b0\u1ee3c\tsinh\tra\tb\u1edfi\tm\u1ed9t\tngu\u1ed3n\t\u00e1nh\ts\u00e1ng\ttr\u00ean\tm\u1eb7t\t\u0111\u1ea5t\t(\u0111\u1ecbnh\tlu\u1eadt Doppler).\t Nh\u1eefng\t l\u1eadp\t lu\u1eadn\t th\u1ef1c\t nghi\u1ec7m\t h\u1ed7\t tr\u1ee3\t cho\t thuy\u1ebft Maxwell-Lorentz\t\u0111\u1ed3ng\tth\u1eddi\tc\u0169ng\tl\u00e0\tnh\u1eefng\tl\u1eadp\tlu\u1eadn\th\u1ed7\ttr\u1ee3\tthuy\u1ebft t\u01b0\u01a1ng\t\u0111\u1ed1i,\tch\u00fang\tc\u00f3\tqu\u00e1\tnhi\u1ec1u\t\u0111\u1ec3\tc\u00f3\tth\u1ec3\tk\u1ec3\th\u1ebft\t\u1edf\t\u0111\u00e2y.\tCh\u00fang\tth\u1eadt s\u1ef1\t \u0111\u00e3\t thu\t nh\u1ecf\t l\u1ea1i\t c\u00e1c\t c\u01a1\t h\u1ed9i\t v\u1ec1\t l\u00fd\t thuy\u1ebft\t \u0111\u1ebfn\t \u0111\u1ed9\t kh\u00f4ng\t m\u1ed9t thuy\u1ebft\t n\u00e0o\t kh\u00e1c\t h\u01a1n\t thuy\u1ebft\t Maxwell-Lorentz\t c\u00f3\t th\u1ec3\t \u0111\u1ee9ng\t v\u1eefng \u0111\u01b0\u1ee3c\ttr\u01b0\u1edbc\tkinh\tnghi\u1ec7m\tth\u1ef1c\tti\u1ec5n. Tuy\t nhi\u00ean\t c\u00f3\t hai\t nh\u00f3m\t d\u1eef\t ki\u1ec7n\t thu\t th\u1eadp\t \u0111\u01b0\u1ee3c\t t\u1eeb\t th\u00ed\t nghi\u1ec7m m\u00e0\t thuy\u1ebft\t Maxwell-Dorentz\t ch\u1ec9\t c\u00f3\t th\u1ec3\t c\u1eaft\t ngh\u0129a\t b\u1eb1ng\t c\u00e1ch\t vay m\u01b0\u1ee3n\t th\u00eam\t m\u1ed9t\t gi\u1ea3\t thuy\u1ebft\t h\u1ed7\t tr\u1ee3\t xa\t l\u1ea1\t n\u1ebfu\t kh\u00f4ng\t s\u1eed\t d\u1ee5ng thuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i. Ng\u01b0\u1eddi\t ta\t bi\u1ebft\t r\u1eb1ng,\t c\u00e1c\t tia\t ca-t\u1ed1t,\t v\u00e0\t c\u00e1c\t tia\t \u0111\u01b0\u1ee3c\t g\u1ecdi\t l\u00e0\t tia\t \u03b2 \u0111\u01b0\u1ee3c\t c\u1ea5u\t t\u1ea1o\t b\u1eb1ng\t nh\u1eefng\t h\u1ea1t\t nh\u1ecf\t c\u00f3\t \u0111i\u1ec7n\t t\u00edch\t \u00e2m\t (electron)\t v\u00e0 \u0111\u01b0\u1ee3c\t ph\u00e1t\t ra\t t\u1eeb\t nh\u1eefng\t ch\u1ea5t\t ph\u00f3ng\t x\u1ea1,\t c\u00f3\t qu\u00e1n\t t\u00ednh\t r\u1ea5t\t nh\u1ecf\t v\u00e0 v\u1eadn\t t\u1ed1c\t l\u1edbn.\t B\u1eb1ng\t c\u00e1ch\t kh\u1ea3o\t s\u00e1t\t \u0111\u1ed9\t l\u1ec7ch\t c\u1ee7a\t nh\u1eefng\t tia\t n\u00e0y\t d\u01b0\u1edbi","\u1ea3nh\th\u01b0\u1edfng\tc\u1ee7a\tc\u00e1c\ttr\u01b0\u1eddng\t\u0111i\u1ec7n\tv\u00e0\tt\u1eeb,\tng\u01b0\u1eddi\tta\tc\u00f3\tth\u1ec3\tnghi\u00ean\tc\u1ee9u \u0111\u1ecbnh\t lu\u1eadt\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t c\u00e1c\t h\u1ea1t\t nh\u1ecf\t n\u00e0y\t m\u1ed9t\t c\u00e1ch\t r\u1ea5t\t ch\u00ednh x\u00e1c. Khi\tnghi\u00ean\tc\u1ee9u\tl\u00fd\tthuy\u1ebft\tc\u00e1c\telectron\tn\u00e0y,\tng\u01b0\u1eddi\tta\tph\u1ea3i\tchi\u1ebfn \u0111\u1ea5u\tv\u1edbi\tkh\u00f3\tkh\u0103n\tl\u00e0\tthuy\u1ebft\t\u0111i\u1ec7n\tt\u1eeb\tt\u1ef1\tn\u00f3\tkh\u00f4ng\tc\u00f3\tkh\u1ea3\tn\u0103ng\t\u0111\u01b0a ra\tl\u1eddi\tgi\u1ea3i\tth\u00edch\tv\u1ec1\tb\u1ea3n\tch\u1ea5t\tc\u1ee7a\tch\u00fang.\tB\u1edfi\tv\u00ec\tc\u00e1c\tkh\u1ed1i\tl\u01b0\u1ee3ng\t\u0111i\u1ec7n c\u00f3\t c\u00f9ng\t m\u1ed9t\t d\u1ea5u\t \u0111\u1ea9y\t nhau,\t c\u00e1c\t kh\u1ed1i\t l\u01b0\u1ee3ng\t \u0111i\u1ec7n\t \u00e2m\t t\u1ea1o\t th\u00e0nh electron\tph\u1ea3i\tb\u1ecb\tph\u00e2n\tt\u00e1n\tra\td\u01b0\u1edbi\tt\u00e1c\td\u1ee5ng\t\u0111\u1ea9y\tnhau\tc\u1ee7a\tch\u00fang, n\u1ebfu\tnh\u01b0\tkh\u00f4ng\tc\u00f3\tnh\u1eefng\tl\u1ef1c\tkh\u00e1c\tt\u00e1c\td\u1ee5ng\tgi\u1eefa\tch\u00fang\tv\u1edbi\tnhau, m\u00e0\t b\u1ea3n\t ch\u1ea5t\t c\u1ee7a\t c\u00e1c\t l\u1ef1c\t n\u00e0y\t \u0111\u1ebfn\t nay\t v\u1eabn\t c\u00f2n\t kh\u00f3\t hi\u1ec3u\t \u0111\u1ed1i\t v\u1edbi ch\u00fang\tta[44].\tN\u1ebfu\tb\u00e2y\tgi\u1edd\tch\u00fang\tta\tgi\u1ea3\tthi\u1ebft\tr\u1eb1ng\tc\u00e1c\tkho\u1ea3ng\tc\u00e1ch t\u01b0\u01a1ng\t\u0111\u1ed1i\tgi\u1eefa\tc\u00e1c\tkh\u1ed1i\tl\u01b0\u1ee3ng\t\u0111i\u1ec7n\tt\u1ea1o\tth\u00e0nh\telectron\tv\u1eabn\tkh\u00f4ng thay\t \u0111\u1ed5i\t trong\t qu\u00e1\t tr\u00ecnh\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t electron\t (ngh\u0129a\t l\u00e0\t c\u00f3 m\u1ed9t\ts\u1ef1\tli\u00ean\tk\u1ebft\tc\u1ee9ng\ttheo\tngh\u0129a\tc\u1ee7a\tc\u01a1\th\u1ecdc\tc\u1ed5\t\u0111i\u1ec3n),\tch\u00fang\tta\ts\u1ebd \u0111i\t \u0111\u1ebfn\t m\u1ed9t\t \u0111\u1ecbnh\t lu\u1eadt\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t electron\t kh\u00f4ng\t ph\u00f9\t h\u1ee3p v\u1edbi\tth\u00ed\tnghi\u1ec7m\tth\u1ef1c\tti\u1ec5n.\t\u0110\u01b0\u1ee3c\td\u1eabn\td\u1eaft\tb\u1edfi\tquan\t\u0111i\u1ec3m\tthu\u1ea7n\tt\u00fay h\u00ecnh\t th\u1ee9c,\t H.A.\t Lorentz\t l\u00e0\t ng\u01b0\u1eddi\t \u0111\u1ea7u\t ti\u00ean\t \u0111\u01b0a\t ra\t gi\u1ea3\t thuy\u1ebft\t n\u00f3i r\u1eb1ng\tv\u1eadt\tth\u1ec3\tc\u1ee7a\telectron,\tnh\u01b0\th\u1ec7\tqu\u1ea3\tc\u1ee7a\tchuy\u1ec3n\t\u0111\u1ed9ng,\tch\u1ecbu\tm\u1ed9t s\u1ef1\t co\t l\u1ea1i[45]\t theo\t chi\u1ec1u\t chuy\u1ec3n\t \u0111\u1ed9ng,\t c\u00f3\t c\u01b0\u1eddng\t \u0111\u1ed9\t co\t l\u1ea1i\t t\u1ef7\t l\u1ec7\t v\u1edbi bi\u1ec3u\tth\u1ee9c Gi\u1ea3\tthuy\u1ebft\tn\u00e0y\tkh\u00f4ng\tth\u1ec3\t\u0111\u01b0\u1ee3c\tbi\u1ec7n\tminh\tb\u1eb1ng\tb\u1ea5t\tc\u1ee9\t\u0111i\u1ec1u\tg\u00ec trong\t\u0111i\u1ec7n\tt\u1eeb\th\u1ecdc,\tnhung\tsau\t\u0111\u00f3\tcung\tc\u1ea5p\t\u0111\u01b0\u1ee3c\t\u0111\u1ecbnh\tlu\u1eadt\tchuy\u1ec3n \u0111\u1ed9ng\t \u0111\u1eb7c\t th\u00f9,\t v\u00e0\t \u0111i\u1ec1u\t n\u00e0y\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t x\u00e1c\t nh\u1eadn\t b\u1edfi\t th\u00ed\t nghi\u1ec7m\t v\u1edbi \u0111\u1ed9\tch\u00ednh\tx\u00e1c\tcao\ttrong\tnh\u1eefng\tn\u0103m\tg\u1ea7n\t\u0111\u00e2y. Thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t \u0111\u01b0a\t ch\u00fang\t ta\t \u0111\u1ebfn\t c\u00f9ng\t m\u1ed9t\t \u0111\u1ecbnh\t lu\u1eadt chuy\u1ec3n\t \u0111\u1ed9ng\t m\u00e0\t kh\u00f4ng\t c\u1ea7n\t \u0111\u1ebfn\t m\u1ed9t\t gi\u1ea3\t thuy\u1ebft\t \u0111\u1eb7c\t th\u00f9\t n\u00e0o\t v\u1ec1 c\u1ea5u\ttr\u00fac\tv\u00e0\ts\u1ef1\tv\u1eadn\th\u00e0nh\tc\u1ee7a\telectron.\tT\u01b0\u01a1ng\tt\u1ef1\tnh\u01b0\tth\u1ebf\tl\u00e0\tnh\u1eefng k\u1ebft\t lu\u1eadn\t m\u00e0\t ch\u00fang\t ta\t \u0111\u00e3\t th\u1ea5y\t \u1edf\t \u00a7\t 13\t trong\t th\u00ed\t nghi\u1ec7m\t Fizeau. Thuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\t\u0111\u00e3\tcung\tc\u1ea5p\tk\u1ebft\tqu\u1ea3\tc\u1ee7a\tFizeau,\tm\u00e0\tkh\u00f4ng\tc\u1ea7n \u0111\u1ebfn\tnh\u1eefng\tgi\u1ea3\tthuy\u1ebft\tv\u1ec1\tb\u1ea3n\tch\u1ea5t\tv\u1eadt\tl\u00fd\tc\u1ee7a\tch\u1ea5t\tl\u1ecfng. Nh\u00f3m\t d\u1eef\t ki\u1ec7n\t th\u1ee9\t hai\t t\u00f4i\t mu\u1ed1n\t \u0111\u1ec1\t c\u1eadp\t \u1edf\t \u0111\u00e2y\t li\u00ean\t quan\t \u0111\u1ebfn c\u00e2u\th\u1ecfi,\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tqu\u1ea3\t\u0111\u1ea5t\ttrong\tv\u0169\ttr\u1ee5\tc\u00f3\tg\u00e2y\t\u1ea3nh\th\u01b0\u1edfng c\u1ea3m\tth\u1ee5\t\u0111\u01b0\u1ee3c\tl\u00ean\tc\u00e1c\tth\u00ed\tnghi\u1ec7m\ttr\u00ean\tm\u1eb7t\t\u0111\u1ea5t\thay\tkh\u00f4ng.\tCh\u00fang ta\t \u0111\u00e3\t nh\u1eadn\t x\u00e9t\t trong\t \u00a7\t 5\t r\u1eb1ng\t t\u1ea5t\t c\u1ea3\t nh\u1eefng\t n\u1ed7\t l\u1ef1c\t t\u00ecm\t ki\u1ebfm\t nh\u01b0","th\u1ebf\t\u0111\u1ec1u\td\u1eabn\t\u0111\u1ebfn\tk\u1ebft\tqu\u1ea3\tph\u1ee7\t\u0111\u1ecbnh.\tTr\u01b0\u1edbc\tkhi\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tra \u0111\u1eddi,\t khoa\t h\u1ecdc\t kh\u00f3\t gi\u1ea3i\t th\u00edch\t \u0111\u01b0\u1ee3c\t k\u1ebft\t qu\u1ea3\t ph\u1ee7\t \u0111\u1ecbnh\t n\u00e0y.\t T\u00ecnh hu\u1ed1ng\tc\u1ee5\tth\u1ec3\tl\u00e0\tnh\u01b0\tsau.\tNh\u1eefng\tth\u00e0nh\tki\u1ebfn\tl\u1ed7i\tth\u1eddi\tv\u1ec1\tth\u1eddi\tgian v\u00e0\t kh\u00f4ng\t gian\t \u0111\u00e3\t l\u00e0m\t cho\t ng\u01b0\u1eddi\t ta\t kh\u00f4ng\t nghi\t ng\u1edd\t \u0111\u01b0\u1ee3c\t r\u1eb1ng ph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tGalilei\tl\u00e0\ty\u1ebfu\tt\u1ed1\tquy\u1ebft\t\u0111\u1ecbnh\tcho\tvi\u1ec7c\tchuy\u1ec3n\t\u0111\u1ed5i\tt\u1eeb m\u1ed9t\t v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\t sang\t m\u1ed9t\t c\u00e1i\t kh\u00e1c.\t Gi\u1ea3\t thi\u1ebft\t b\u00e2y\t gi\u1edd,\t c\u00e1c ph\u01b0\u01a1ng\ttr\u00ecnh\tMaxwell-Lorentz\tc\u00f3\thi\u1ec7u\tl\u1ef1c\tcho\tm\u1ed9t\tv\u1eadt\tth\u1ec3\tK,\tth\u00ec ch\u00fang\t ta\t s\u1ebd\t th\u1ea5y\t ch\u00fang\t kh\u00f4ng\t c\u00f3\t hi\u1ec7u\t l\u1ef1c\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed9t\t h\u1ec7\t quy chi\u1ebfu\t K\u2019\t n\u1ebfu\t ng\u01b0\u1eddi\t ta\t gi\u1ea3\t thi\u1ebft\t quan\t h\u1ec7\t t\u1ed3n\t t\u1ea1i\t gi\u1eefa\t K\t v\u00e0\t K\u2019\t l\u00e0 ph\u00e9p\t bi\u1ebfn\t \u0111\u1ed5i\t Galilei.\t Nh\u01b0\t th\u1ebf\t c\u00f3\t ngh\u0129a\t r\u1eb1ng\t trong\t t\u1ea5t\t c\u1ea3\t c\u00e1c\t h\u1ec7 t\u1ecda\t\u0111\u1ed9\tGalilei\tc\u00f3\tm\u1ed9t\th\u1ec7\t(K)\tv\u1edbi\tm\u1ed9t\ttr\u1ea1ng\tth\u00e1i\tchuy\u1ec3n\t\u0111\u1ed9ng\tn\u00e0o \u0111\u00f3\tc\u00f3\tt\u00ednh\tch\u1ea5t\t\u0111\u1eb7c\tbi\u1ec7t\tv\u1ec1\tm\u1eb7t\tv\u1eadt\tl\u00fd.\tNg\u01b0\u1eddi\tta\tdi\u1ec5n\tgi\u1ea3i\tk\u1ebft\tqu\u1ea3 n\u00e0y\t theo\t h\u01b0\u1edbng\t xem\t K\t nh\u01b0\t \u0111\u1ee9ng\t y\u00ean\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed9t\t b\u1ec3\t ether\t \u0111\u01b0\u1ee3c gi\u1ea3\t\u0111\u1ecbnh\tt\u1ed3n\tt\u1ea1i.\tNg\u01b0\u1ee3c\tl\u1ea1i,\tt\u1ea5t\tc\u1ea3\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\tK'\tchuy\u1ec3n\t\u0111\u1ed9ng\t\u0111\u1ed1i\tv\u1edbi K\t \u0111\u01b0\u1ee3c\t xem\t nh\u01b0\t chuy\u1ec3n\t \u0111\u1ed9ng\t v\u1edbi\t ether.\t Ng\u01b0\u1eddi\t ta\t \u0111\u00e3\t g\u00e1n\t cho chuy\u1ec3n\t \u0111\u1ed9ng\t n\u00e0y\t c\u1ee7a\t K'\t \u0111\u1ed1i\t v\u1edbi\t ether\t (\\\"Gi\u00f3\t ether\\\"[46]\t \u0111\u1ed1i\t v\u1edbi\t K') nh\u1eefng\t\u0111\u1ecbnh\tlu\u1eadt\tph\u1ee9c\tt\u1ea1p\th\u01a1n\tc\u1ea7n\tph\u1ea3i\tc\u00f3\thi\u1ec7u\tl\u1ef1c\t\u0111\u1ed1i\tv\u1edbi\tK\u2019.\tDo \u0111\u00f3,\t\u0111\u1ed1i\tv\u1edbi\tqu\u1ea3\t\u0111\u1ea5t,\tm\u1ed9t\tgi\u1ea3\tthuy\u1ebft\tv\u1ec1\ts\u1ef1\tt\u1ed3n\tt\u1ea1i\tc\u1ee7a\tgi\u00f3\tether\tnh\u01b0 th\u1ebf\tc\u0169ng\tph\u1ea3i\t\u0111\u01b0\u1ee3c\tch\u1ea5p\tnh\u1eadn,\tv\u00e0\ts\u1ef1\tn\u1ed7\tl\u1ef1c\tm\u1ed9t\tth\u1eddi\tgian\td\u00e0i\tc\u1ee7a c\u00e1c\tnh\u00e0\tv\u1eadt\tl\u00fd\tl\u00e0\tnh\u1eb1m\t\u0111\u1ec3\tch\u1ee9ng\tminh\t\u0111i\u1ec1u\t\u0111\u00f3. \u0110\u1ec3\tch\u1ee9ng\tminh,\tMichelson\t\u0111\u00e3\tt\u00ecm\tra\tm\u1ed9t\tph\u01b0\u01a1ng\tph\u00e1p\txem\tra c\u00f3\t t\u00ednh\t ch\u1ea5t\t quy\u1ebft\t \u0111\u1ecbnh.\t H\u00e3y\t t\u01b0\u01a1ng\t t\u01b0\u1ee3ng\t hai\t t\u1ea5m\t g\u01b0\u01a1ng\t \u0111\u01b0\u1ee3c g\u1eafn\t v\u00e0o\t m\u1ed9t\t v\u1eadt\t th\u1ec3\t r\u1eafn,\t quay\t b\u1ec1\t m\u1eb7t\t ph\u1ea3n\t chi\u1ebfu\t l\u1ea1i\t nhau.\t M\u1ed9t tia\t s\u00e1ng\t c\u1ea7n\t m\u1ed9t\t th\u1eddi\t gian\t nh\u1ea5t\t \u0111\u1ecbnh\t T\t \u0111\u1ec3\t \u0111i\t t\u1eeb\t m\u1ed9t\t g\u01b0\u01a1ng\t n\u00e0y \u0111\u1ebfn\t g\u01b0\u01a1ng\t kia\t v\u00e0\t tr\u1edf\t l\u1ea1i,\t n\u1ebfu\t c\u1ea3\t h\u1ec7\t th\u1ed1ng\t \u0111\u1ee9ng\t y\u00ean\t \u0111\u1ed1i\t v\u1edbi\t b\u1ec3 ether.\t Tuy\t nhi\u00ean,\t khi\t v\u1eadt\t th\u1ec3\t c\u00f9ng\t v\u1edbi\t c\u00e1c\t g\u01b0\u01a1ng\t chuy\u1ec3n\t \u0111\u1ed9ng \u0111\u1ed1i\t v\u1edbi\t ether,\t ng\u01b0\u1eddi\t ta\t s\u1ebd\t t\u00ecm\t th\u1ea5y\t qua\t t\u00ednh\t to\u00e1n\t m\u1ed9t\t th\u1eddi\t gian h\u01a1i\t kh\u00e1c\t \u0111i\t l\u00e0\t T'\t cho\t di\u1ec5n\t bi\u1ebfn\t tr\u00ean.\t Ch\u01b0a\t h\u1ebft:\t t\u00ednh\t to\u00e1n\t c\u0169ng\t s\u1ebd cho\tth\u1ea5y,\tv\u1edbi\tv\u1eadn\tt\u1ed1c\tchuy\u1ec3n\t\u0111\u1ed9ng\tv\t\u0111\u1ed1i\tv\u1edbi\tb\u1ec3\tether,\tth\u1eddi\tgian\tT' khi\tv\u1eadt\tth\u1ec3\tchuy\u1ec3n\t\u0111\u1ed9ng\tth\u1eb3ng\tg\u00f3c\tv\u1edbi\tc\u00e1c\tm\u1eb7t\tph\u1eb3ng\tc\u1ee7a\tg\u01b0\u01a1ng s\u1ebd\t kh\u00e1c\t h\u01a1n\t khi\t n\u00f3\t chuy\u1ec3n\t \u0111\u1ed9ng\t song\t song\t v\u1edbi\t g\u01b0\u01a1ng.\t S\u1ef1\t kh\u00e1c bi\u1ec7t\t\u0111\u01b0\u1ee3c\tt\u00ednh\tto\u00e1n\tnh\u01b0\tth\u1ebf\tgi\u1eefa\thai\tth\u1eddi\tl\u01b0\u1ee3ng,\td\u00f9\tnh\u1ecf\t\u0111\u1ebfn\t\u0111\u00e2u, c\u0169ng\t s\u1ebd\t ph\u1ea3i\t hi\u1ec7n\t ra\t n\u1ebfu\t Michelson\t v\u00e0\t Morley\t th\u1ef1c\t hi\u1ec7n\t th\u00ed nghi\u1ec7m\t giao\t thoa.\t Tuy\t nhi\u00ean,\t th\u00ed\t nghi\u1ec7m\t k\u1ebft\t c\u1ee5c\t m\u1ed9t\t c\u00e1ch\t ph\u1ee7 \u0111\u1ecbnh,\ttr\u01b0\u1edbc\ts\u1ef1\tb\u1ed1i\tr\u1ed1i\tl\u1edbn\tc\u1ee7a\tc\u00e1c\tnh\u00e0\tv\u1eadt\tl\u00fd.\tLorentz\tv\u00e0\tFitzgerald c\u1ee9u\tv\u00e3n\tl\u00fd\tthuy\u1ebft\t(ether)\tkh\u1ecfi\ts\u1ef1\tb\u1ed1i\tr\u1ed1i\tn\u00e0y\tb\u1eb1ng\tc\u00e1ch\tgi\u1ea3\t\u0111\u1ecbnh chuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\tv\u1eadt\tth\u1ec3\t\u0111\u1ed1i\tv\u1edbi\tether\tg\u00e2y\tra\tm\u1ed9t\ts\u1ef1\tco\tl\u1ea1i\tc\u1ee7a\tn\u00f3 theo\t chi\u1ec1u\t chuy\u1ec3n\t \u0111\u1ed9ng,\t b\u1eb1ng\t m\u1ed9t\t l\u01b0\u1ee3ng\t v\u1eeba\t \u0111\u1ee7\t \u0111\u1ec3\t l\u00e0m\t cho\t s\u1ef1","kh\u00e1c\tbi\u1ec7t\tth\u1eddi\tgian\tn\u00f3i\ttr\u00ean\tbi\u1ebfn\tm\u1ea5t.\tM\u1ed9t\ts\u1ef1\tso\ts\u00e1nh\tv\u1edbi\tc\u00e1c\t\u0111i\u1ec1u tr\u00ecnh\tb\u00e0y\ttrong\t\u00a7\t12\tcho\tth\u1ea5y,\tl\u1ed1i\ttho\u00e1t\tn\u00e0y\tc\u0169ng\tl\u00e0\t\u0111\u00fang\t\u0111\u1eafn\t\u0111\u1ed1i v\u1edbi\t quan\t \u0111i\u1ec3m\t c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i.\t Tuy\t nhi\u00ean\t ph\u01b0\u01a1ng\t ph\u00e1p di\u1ec5n\t\u0111\u1ea1t\tt\u00ecnh\thu\u1ed1ng\td\u1ef1a\ttr\u00ean\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\tl\u00e0\tth\u1ecfa\t\u0111\u00e1ng\th\u01a1n kh\u00f4ng\tg\u00ec\ts\u00e1nh\tk\u1ecbp.\tTheo\t\u0111\u00f3,\tkh\u00f4ng\tc\u00f3\tm\u1ed9t\th\u1ec7\tt\u1ecda\t\u0111\u1ed9\t\u01b0u\t\u0111\u00e3i,\tc\u00e1i\t\u0111\u00e3 l\u00e0m\tn\u00ean\tnguy\u00ean\tc\u1edb\tcho\tvi\u1ec7c\th\u00ecnh\tth\u00e0nh\t\u00fd\tt\u01b0\u1edfng\tether,\tv\u00e0\tv\u00ec\tth\u1ebf c\u0169ng\t kh\u00f4ng\t c\u00f3\t gi\u00f3\t ether,\t v\u00e0\t kh\u00f4ng\t c\u00f3\t th\u00ed\t nghi\u1ec7m\t n\u00e0o\t \u0111\u1ec3\t minh ch\u1ee9ng\t\u0111\u01b0\u1ee3c\tn\u00f3.\t\u1ede\t\u0111\u00e2y\ts\u1ef1\tco\tl\u1ea1i\tc\u1ee7a\tc\u00e1c\tv\u1eadt\tth\u1ec3\tchuy\u1ec3n\t\u0111\u1ed9ng\t\u0111\u01b0\u1ee3c suy\t ra\t t\u1eeb\t hai\t nguy\u00ean\t l\u00fd\t c\u01a1\t b\u1ea3n\t c\u1ee7a\t l\u00fd\t thuy\u1ebft\t m\u00e0\t kh\u00f4ng\t c\u1ea7n\t c\u00e1c gi\u1ea3\t thuy\u1ebft\t ph\u1ee5.\t Th\u1ef1c\t t\u1ebf,\t y\u1ebfu\t t\u1ed1\t quy\u1ebft\t \u0111\u1ecbnh\t cho\t s\u1ef1\t co\t l\u1ea1i\t n\u00e0y kh\u00f4ng\t ph\u1ea3i\t l\u00e0\t chuy\u1ec3n\t \u0111\u1ed9ng\t t\u1ef1\t n\u00f3,\t c\u00e1i\t ch\u00fang\t ta\t kh\u00f4ng\t th\u1ec3\t g\u00e1n m\u1ed9t\t \u00fd\t ngh\u0129a\t n\u00e0o,\t m\u00e0\t ch\u00ednh\t l\u00e0\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u1ed1i\t v\u1edbi\t v\u1eadt\t th\u1ec3\t quy chi\u1ebfu\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t ch\u1ecdn.\t Do\t \u0111\u00f3,\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed9t\t h\u1ec7\t quy\t chi\u1ebfu\t chuy\u1ec3n \u0111\u1ed9ng\t c\u00f9ng\t v\u1edbi\t qu\u00e1\t \u0111\u1ea5t,\t h\u1ec7\t th\u1ed1ng\t g\u01b0\u01a1ng\t c\u1ee7a\t Michelson\t v\u00e0\t Morley kh\u00f4ng\tb\u1ecb\tthu\tng\u1eafn\tl\u1ea1i,\tnh\u01b0ng\tn\u00f3\ts\u1ebd\tb\u1ecb\tthu\tng\u1eafn\tl\u1ea1i\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\th\u1ec7 quy\tchi\u1ebfu\t\u0111\u1ee9ng\ty\u00ean\t\u0111\u1ed1i\tv\u1edbi\tm\u1eb7t\ttr\u1eddi.","\u00a7\t17 Kh\u00f4ng\tGian\tMinkowski\tB\u1ed1n\tChi\u1ec1u M\u1ed9t\t ng\u01b0\u1eddi\t kh\u00f4ng\t am\t hi\u1ec3u\t to\u00e1n\t h\u1ecdc\t s\u1ebd\t b\u1ecb\t m\u1ed9t\t c\u1ea3m\t gi\u00e1c\t s\u1ee3\t h\u00e3i x\u00e2m\t chi\u1ebfm\t ngay\t n\u1ebfu\t nghe\t \u0111\u1ebfn\t c\u00e1c\t s\u1ef1\t v\u1eadt\t \\\"b\u1ed1n\t chi\u1ec1u\\\",\t m\u1ed9t\t c\u1ea3m gi\u00e1c\tkh\u00f4ng\tph\u1ea3i\tkh\u00f4ng\tgi\u1ed1ng\tc\u00e1i\tc\u1ea3m\tgi\u00e1c\ts\u1ef1\th\u00e3i\t\u0111\u01b0\u1ee3c\tg\u00e2y\tra\tb\u1edfi nh\u1eefng\tsuy\tngh\u0129\tsi\u00eau\tnhi\u00ean\tth\u1ea7n\tb\u00ed.\tNh\u01b0ng\tkh\u00f4ng\tc\u00f3\tc\u00e2u\tn\u00f3i\tn\u00e0o l\u1ea1i\t b\u00ecnh\t th\u01b0\u1eddng\t h\u01a1n\t l\u00e0\t c\u00e2u\t n\u00f3i:\t th\u1ebf\t gi\u1edbi\t ch\u00fang\t ta\t \u0111ang\t s\u1ed1ng\t l\u00e0 m\u1ed9t\tcontinum[47]\tkh\u00f4ng-th\u1eddi-gian\tb\u1ed1n\tchi\u1ec1u. Kh\u00f4ng\tgian\tl\u00e0\tm\u1ed9t\tcontinum\tba\tchi\u1ec1u.\t\u0110i\u1ec1u\tn\u00e0y\tmu\u1ed1n\tn\u00f3i\tl\u00ean r\u1eb1ng\t ng\u01b0\u1eddi\t ta\t c\u00f3\t th\u1ec3\t m\u00f4\t t\u1ea3\t v\u1ecb\t tr\u00ed\t c\u1ee7a\t m\u1ed9t\t \u0111i\u1ec3m\t (\u0111\u1ee9ng\t y\u00ean)\t b\u1eb1ng ba\t\u0111\u1ea1i\tl\u01b0\u1ee3ng\t(g\u1ecdi\tl\u00e0\tt\u1ecda\t\u0111\u1ed9)\tx,\ty,\tz,\tv\u00e0\tm\u1ed7i\t\u0111i\u1ec3m\tnh\u01b0\tth\u1ebf\tc\u00f3\tnh\u1eefng \u0111i\u1ec3m\t\\\"l\u00e1ng\tgi\u1ec1ng\\\"\t\u1edf\tg\u1ea7n\tb\u1ea5t\tk\u1ef3,\tm\u00e0\tv\u1ecb\ttr\u00ed\t\u0111\u01b0\u1ee3c\tm\u00f4\tt\u1ea3\tb\u1eb1ng\tc\u00e1c\ttr\u1ecb s\u1ed1\t t\u1ecda\t \u0111\u1ed9\t x1,\t y1,\t z1,\t c\u00f3\t th\u1ec3\t ti\u1ebfn\t g\u1ea7n\t c\u00e1c\t t\u1ecda\t \u0111\u1ed9\t x,\t y,\t z\t c\u1ee7a\t \u0111i\u1ec3m tr\u01b0\u1edbc\t m\u1ed9t\t c\u00e1ch\t b\u1ea5t\t k\u1ef3.\t Do\t t\u00ednh\t ch\u1ea5t\t sau,\t ch\u00fang\t ta\t n\u00f3i\t \u0111\u00f3\t l\u00e0\t m\u1ed9t \\\"continum\\\",\t v\u00e0\t do\t con\t s\u1ed1\t b\u1ed9\t ba\t c\u1ee7a\t c\u00e1c\t t\u1ecda\t \u0111\u1ed9\t ch\u00fang\t ta\t n\u00f3i\t \\\"ba chi\u1ec1u\\\". T\u01b0\u01a1ng\t t\u1ef1\t nh\u01b0\t th\u1ebf\t l\u00e0\t th\u1ebf\t gi\u1edbi\t c\u1ee7a\t nh\u1eefng\t hi\u1ec7n\t t\u01b0\u1ee3ng\t v\u1eadt\t l\u00fd, \u0111\u01b0\u1ee3c\tMinkowski\tg\u1ecdi\tng\u1eafn\tg\u1ecdn\tl\u00e0\t\\\"th\u1ebf\tgi\u1edbi\\\"[48],\td\u0129\tnhi\u00ean\tb\u1ed1n\tchi\u1ec1u theo\t ngh\u0129a\t kh\u00f4ng-th\u1eddi-gian.\t V\u00ec\t n\u00f3\t \u0111\u01b0\u1ee3c\t t\u1ea1o\t th\u00e0nh\t b\u1eb1ng\t c\u00e1c\t s\u1ef1 ki\u1ec7n\tc\u00e1\tnh\u00e2n,\tm\u1ed7i\tc\u00e1i\ttrong\t\u0111\u00f3\t\u0111\u01b0\u1ee3c\tm\u00f4\tt\u1ea3\tb\u1eb1ng\tb\u1ed1n\ts\u1ed1,\t\u0111\u00f3\tl\u00e0\tba t\u1ecda\t \u0111\u1ed9\t kh\u00f4ng\t gian\t x,\t y,\t z\t v\u00e0\t m\u1ed9t\t t\u1ecda\t \u0111\u1ed9\t th\u1eddi\t gian,\t tr\u1ecb\t s\u1ed1\t t.\t \\\"Th\u1ebf gi\u1edbi\\\"\tc\u0169ng\tl\u00e0\tm\u1ed9t\tcontinum\ttheo\tngh\u0129a\ttr\u00ean;\tb\u1edfi\tv\u00ec\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed7i\ts\u1ef1 ki\u1ec7n\t \u0111\u00e3\t cho,\t ta\t c\u00f3\t nh\u1eefng\t s\u1ef1\t ki\u1ec7n\t \\\"l\u00e1ng\t gi\u1ec1ng\\\"\t b\u1ea5t\t k\u1ef3\t (\u0111\u01b0\u1ee3c\t th\u1ef1c hi\u1ec7n\thay\tc\u00f3\tth\u1ec3\tquan\tni\u1ec7m\t\u0111\u01b0\u1ee3c)\tm\u00e0\tt\u1ecda\t\u0111\u1ed9\tc\u1ee7a\tch\u00fang\tx1,\ty1,\tz1, t1\t kh\u00e1c\t v\u1edbi\t t\u1ecda\t \u0111\u1ed9\t c\u1ee7a\t s\u1ef1\t ki\u1ec7n\t cho\t tr\u01b0\u1edbc\t b\u1edfi\t m\u1ed9t\t l\u01b0\u1ee3ng\t nh\u1ecf\t b\u1ea5t k\u1ef3.\t Ch\u00fang\t ta\t \u0111\u00e3\t kh\u00f4ng\t quen\t g\u1ecdi\t th\u1ebf\t gi\u1edbi\t trong\t ngh\u0129a\t n\u00e0y\t b\u1eb1ng continum\t b\u1ed1n\t chi\u1ec1u.\t L\u00fd\t do\t l\u00e0\t th\u1eddi\t gian\t trong\t v\u1eadt\t l\u00fd\t ti\u1ec1n-t\u01b0\u01a1ng- \u0111\u1ed1i\t\u0111\u00f3ng\tm\u1ed9t\tvai\ttr\u00f2\tkh\u00e1c,\t\u0111\u1ed9c\tl\u1eadp\th\u01a1n\t\u0111\u1ed1i\tv\u1edbi\tt\u1ecda\t\u0111\u1ed9\tkh\u00f4ng\tgian. Cho\tn\u00ean\tch\u00fang\tta\t\u0111\u00e3\tquen\txem\tth\u1eddi\tgian\tnh\u01b0\tm\u1ed9t\tcontinum\t\u0111\u1ed9c l\u1eadp.\t Trong\t th\u1ef1c\t t\u1ebf,\t theo\t v\u1eadt\t l\u00fd\t c\u1ed5\t \u0111i\u1ec3n,\t th\u1eddi\t gian\t l\u00e0\t tuy\u1ec7t\t \u0111\u1ed1i, ngh\u0129a\t l\u00e0\t \u0111\u1ed9c\t l\u1eadp\t v\u1edbi\t v\u1ecb\t tr\u00ed\t v\u00e0\t tr\u1ea1ng\t th\u00e1i\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t h\u1ec7\t quy chi\u1ebfu.\t \u0110i\u1ec1u\t n\u00e0y\t \u0111\u01b0\u1ee3c\t bi\u1ec3u\t l\u1ed9\t trong\t ph\u01b0\u01a1ng\t tr\u00ecnh\t cu\u1ed1i\t c\u1ee7a\t ph\u00e9p bi\u1ebfn\t\u0111\u1ed5i\tGalilei\t(t\u2019\t=\tt). Thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t \u0111\u00e3\t \u0111em\t l\u1ea1i\t c\u00e1ch\t xem\t x\u00e9t\t \\\"th\u1ebf\t gi\u1edbi\\\"\t \u1edf\t d\u1ea1ng b\u1ed1n\tchi\u1ec1u\tm\u1ed9t\tc\u00e1ch\tt\u1ef1\tnhi\u00ean,\tb\u1edfi\tv\u00ec\ttheo\tl\u00fd\tthuy\u1ebft\tn\u00e0y\tth\u1eddi\tgian","\u0111\u00e3\tb\u1ecb\tc\u01b0\u1edbp\tm\u1ea5t\tt\u00ednh\t\u0111\u1ed9c\tl\u1eadp\tc\u1ee7a\tn\u00f3,\tnh\u01b0\tph\u01b0\u01a1ng\ttr\u00ecnh\tth\u1ee9\tt\u01b0\tc\u1ee7a ph\u00e9p\tbi\u1ebfn\t\u0111\u1ed5i\tLorentz\tcho\tth\u1ea5y: H\u01a1n\t n\u1eefa,\t theo\t ph\u01b0\u01a1ng\t tr\u00ecnh\t n\u00e0y,\t kho\u1ea3ng\t c\u00e1ch\t th\u1eddi\t gian\t \u0394t\u2019 c\u1ee7a\t hai\t s\u1ef1\t ki\u1ec7n\t \u0111\u1ed1i\t v\u1edbi\t K'\t n\u00f3i\t chung\t kh\u00f4ng\t tri\u1ec7t\t ti\u00eau,\t ngay\t khi kho\u1ea3ng\t c\u00e1ch\t \u0394t\t c\u1ee7a\t c\u00f9ng\t nh\u1eefng\t s\u1ef1\t ki\u1ec7n\t \u0111\u1ed1i\t v\u1edbi\t K\t tri\u1ec7t\t ti\u00eau. \\\"Kho\u1ea3ng\t c\u00e1ch\t kh\u00f4ng\t gian\\\"\t thu\u1ea7n\t t\u00fay\t c\u1ee7a\t hai\t hi\u1ec7n\t t\u01b0\u1ee3ng\t \u0111\u1ed1i\t v\u1edbi K\t\u0111\u00e3\tsinh\tra\th\u1ec7\tqu\u1ea3\tl\u00e0\tm\u1ed9t\t\\\"kho\u1ea3ng\tc\u00e1ch\tth\u1eddi\tgian\\\"\tc\u1ee7a\tc\u00f9ng\tc\u00e1c hi\u1ec7n\t t\u01b0\u1ee3ng\t \u0111\u1ed1i\t v\u1edbi\t K\u2019.\t Nh\u01b0ng\t \u00fd\t ngh\u0129a\t quan\t tr\u1ecdng\t c\u1ee7a\t s\u1ef1\t kh\u00e1m ph\u00e1\tc\u1ee7a\tMinkowski\tcho\ts\u1ef1\tph\u00e1t\ttri\u1ec3n\th\u00ecnh\tth\u1ee9c\tc\u1ee7a\tthuy\u1ebft\tt\u01b0\u01a1ng \u0111\u1ed1i\tc\u0169ng\tkh\u00f4ng\tph\u1ea3i\tn\u1eb1m\t\u1edf\t\u0111\u00e2y.\tN\u00f3\tn\u1eb1m\tnhi\u1ec1u\th\u01a1n\t\u1edf\tnh\u1eadn\tth\u1ee9c r\u1eb1ng\tc\u00e1i\tcontinum\tb\u1ed1n\tchi\u1ec1u\tc\u1ee7a\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i,\tx\u00e9t\tv\u1ec1\tnh\u1eefng t\u00ednh\t ch\u1ea5t\t h\u00ecnh\t th\u1ee9c\t c\u01a1\t b\u1ea3n\t c\u1ee7a\t n\u00f3[49],\t c\u00f3\t mang\t trong\t m\u00ecnh\t t\u00ednh ch\u1ea5t\t h\u1ecd\t h\u00e0ng\t r\u00f5\t r\u1ec7t\t nh\u1ea5t\t v\u1edbi\t continum\t ba\t chi\u1ec1u\t c\u1ee7a\t kh\u00f4ng\t gian h\u00ecnh\th\u1ecdc\tEuclid.\t\u0110\u1ec3\tl\u00e0m\tcho\ts\u1ef1\tgi\u1ed1ng\tnhau\tn\u00e0y\thi\u1ec7n\tr\u00f5\tra,\tthay\tv\u00ec t\u1ecda\t\u0111\u1ed9\tth\u1eddi\tgian\tth\u00f4ng\tth\u01b0\u1eddng\tt,\tch\u00fang\tta\t\u0111\u01b0a\tv\u00e0o\t\u0111\u1ea1i\tl\u01b0\u1ee3ng\t\u1ea3o\tct t\u1ec9\tl\u1ec7[50]\t v\u1edbi\t n\u00f3.\t B\u1eb1ng\t c\u00e1ch\t n\u00e0y,\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1\t nhi\u00ean\t th\u1ecfa\t m\u00e3n thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p\t s\u1ebd\t c\u00f3\t d\u1ea1ng\t to\u00e1n\t h\u1ecdc\t m\u00e0\t \u1edf\t \u0111\u00f3\t t\u1ecda\t \u0111\u1ed9\t th\u1eddi gian\t\u0111\u00f3ng\tvai\ttr\u00f2\tgi\u1ed1ng\tnh\u01b0\tvai\ttr\u00f2\tc\u1ee7a\tba\tt\u1ecda\t\u0111\u1ed9\tkh\u00f4ng\tgian.\tB\u1ed1n t\u1ecda\t \u0111\u1ed9\t n\u00e0y\t t\u01b0\u01a1ng\t \u1ee9ng\t v\u1ec1\t h\u00ecnh\t th\u1ee9c\t ch\u00ednh\t x\u00e1c\t ba\t t\u1ecda\t \u0111\u1ed9\t kh\u00f4ng gian\t c\u1ee7a\t h\u00ecnh\t h\u1ecdc\t Euclid.\t M\u1ed9t\t ng\u01b0\u1eddi\t kh\u00f4ng\t \u1edf\t trong\t ng\u00e0nh\t to\u00e1n c\u0169ng\t nh\u1eadn\t th\u1ea5y\t d\u1ec5\t d\u00e0ng\t r\u1eb1ng,\t b\u1eb1ng\t nh\u1eadn\t th\u1ee9c\t thu\u1ea7n\t t\u00fay\t h\u00ecnh th\u1ee9c\tn\u00e0y,\tthuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\t\u0111\u00e3\t\u0111\u1ea1t\t\u0111\u01b0\u1ee3c\ts\u1ef1\ts\u00e1ng\ts\u1ee7a\t\u0111\u1eb7c\tbi\u1ec7t. S\u1ef1\tph\u00e1c\th\u1ecda\t\u00edt\t\u1ecfi\ttr\u00ean\t\u0111\u00e2y\tch\u1ec9\t\u0111em\t\u0111\u1ebfn\tcho\tng\u01b0\u1eddi\t\u0111\u1ecdc\tm\u1ed9t\th\u00ecnh dung\t m\u01a1\t h\u1ed3\t v\u1ec1\t \u00fd\t t\u01b0\u1edfng\t quan\t tr\u1ecdng\t c\u1ee7a\t Minkowski,\t \u00fd\t t\u01b0\u1edfng\t m\u00e0 n\u1ebfu\t kh\u00f4ng\t c\u00f3\t n\u00f3,\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng\t v\u1edbi\t nh\u1eefng\t \u00fd\t t\u01b0\u1edfng\t c\u01a1 b\u1ea3n\tc\u1ee7a\tn\u00f3\t\u0111\u01b0\u1ee3c\tph\u00e1t\ttri\u1ec3n\tsau\t\u0111\u00e2y,\tc\u00f3\tl\u1ebd\tv\u1eabn\tc\u00f2n\tn\u1eb1m\ttrong\tgiai \u0111o\u1ea1n\t \u1ea5u\t tr\u0129.\t V\u00ec\t m\u1ed9t\t s\u1ef1\t di\u1ec5n\t \u0111\u1ea1t\t chu\u1ea9n\t x\u00e1c\t h\u01a1n\t \u00fd\t t\u01b0\u1edfng\t n\u00e0y,\t v\u1ed1n \u0111\u00e3\t r\u1ea5t\t kh\u00f3\t hi\u1ec3u\t \u0111\u1ed1i\t v\u1edbi\t m\u1ed9t\t ng\u01b0\u1eddi\t kh\u00f4ng\t kinh\t nghi\u1ec7m\t v\u1edbi\t to\u00e1n h\u1ecdc,\t kh\u00f4ng\t \u00edch\t l\u1ee3i\t l\u1eafm\t cho\t vi\u1ec7c\t hi\u1ec3u\t bi\u1ebft\t nh\u1eefng\t \u00fd\t t\u01b0\u1edfng\t ch\u00ednh c\u1ee7a\t thuy\u1ebft\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p\t hay\t r\u1ed9ng,\t n\u00ean\t t\u00f4i\t mu\u1ed1n\t t\u1ea1m\t d\u1eebng\t \u1edf \u0111\u00e2y,\tv\u00e0\ts\u1ebd\ttr\u1edf\tl\u1ea1i\ttrong\tph\u1ea7n\ttr\u00ecnh\tb\u00e0y\t\u1edf\tcu\u1ed1i\tcu\u1ed1n\ts\u00e1ch\tn\u00e0y.","","Ph\u1ea7n\tII THUY\u1ebeT\tT\u01af\u01a0NG\t\u0110\u1ed0I\tR\u1ed8NG (\u00a7\t18\t-\t\u00a7\t29) \u00a7\t18 Nguy\u00ean\tL\u00fd\tT\u01b0\u01a1ng\t\u0110\u1ed1i\tH\u1eb9p\tV\u00e0\tR\u1ed9ng Lu\u1eadn\t \u0111\u1ec1\t c\u01a1\t b\u1ea3n\t m\u00e0\t t\u1ea5t\t c\u1ea3\t nh\u1eefng\t \u00fd\t t\u01b0\u1edfng\t \u0111\u01b0\u1ee3c\t tr\u00ecnh\t b\u00e0y\t \u0111\u1ebfn nay\t \u0111\u1ec1u\t xoay\t quanh\t ch\u00ednh\t l\u00e0\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p,\t ngh\u0129a\t l\u00e0, nguy\u00ean\t l\u00fd\t c\u1ee7a\t t\u00ednh\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t v\u1eadt\t l\u00fd\t c\u1ee7a\t m\u1ecdi\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u1ec1u. Ch\u00fang\t ta\t h\u00e3y\t ph\u00e2n\t t\u00edch\t l\u1ea1i\t m\u1ed9t\t l\u1ea7n\t n\u1eefa\t n\u1ed9i\t dung\t c\u1ee7a\t n\u00f3\t m\u1ed9t c\u00e1ch\tch\u00ednh\tx\u00e1c. M\u1ecdi\t chuy\u1ec3n\t \u0111\u1ed9ng,\t theo\t kh\u00e1i\t ni\u1ec7m\t c\u1ee7a\t n\u00f3,\t ph\u1ea3i\t \u0111\u01b0\u1ee3c\t quan ni\u1ec7m\tch\u1ec9\tl\u00e0\tchuy\u1ec3n\t\u0111\u1ed9ng\tt\u01b0\u01a1ng\t\u0111\u1ed1i,\t\u0111i\u1ec1u\t\u0111\u00f3\tth\u1eddi\tn\u00e0o\tai\tc\u00f9ng\tth\u1ea5y \u0111\u01b0\u1ee3c.\t\u1ede\tth\u00ed\td\u1ee5\tn\u1ec1n\tray\tv\u00e0\txe\tl\u1eeda\t\u0111\u01b0\u1ee3c\td\u00f9ng\tr\u1ea5t\tnhi\u1ec1u\tl\u1ea7n,\tch\u00fang ta\tc\u00f3\tth\u1ec3\tbi\u1ec3u\tth\u1ecb\ts\u1ef1\tchuy\u1ec3n\t\u0111\u1ed9ng\tdi\u1ec5n\tra\t\u1edf\t\u0111\u00e2y\td\u01b0\u1edbi\thai\td\u1ea1ng\tsau m\u1ed9t\tc\u00e1ch\tb\u00ecnh\t\u0111\u1eb3ng: (a)\tXe\tl\u1eeda\tchuy\u1ec3n\t\u0111\u1ed9ng\tt\u01b0\u01a1ng\t\u0111\u1ed1i\t\u0111\u1ed1i\tv\u1edbi\tn\u1ec1n\tray. (b)\tN\u1ec1n\tray\tchuy\u1ec3n\t\u0111\u1ed9ng\tt\u01b0\u01a1ng\t\u0111\u1ed1i\t\u0111\u1ed1i\tv\u1edbi\txe\tl\u1eeda. Trong\t tr\u01b0\u1eddng\t h\u1ee3p\t (a),\t n\u1ec1n\t ray\t \u0111\u01b0\u1ee3c\t xem\t nh\u01b0\t v\u1eadt\t th\u1ec3\t quy chi\u1ebfu;\t trong\t tr\u01b0\u1eddng\t h\u1ee3p\t (b)\t xe\t l\u1eeda\t l\u00e0\t v\u1eadt\t quy\t chi\u1ebfu.\t N\u1ebfu\t ch\u1ec9\t \u0111\u1ec3 x\u00e1c\tnh\u1eadn\thay\tm\u00f4\tt\u1ea3\tm\u1ed9t\tchuy\u1ec3n\t\u0111\u1ed9ng\tth\u00ec\tquy\tchi\u1ebfu\tchuy\u1ec3n\t\u0111\u1ed9ng l\u00ean\t v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\t n\u00e0o,\t \u0111i\u1ec1u\t \u0111\u00f3\t v\u1ec1\t c\u01a1\t b\u1ea3n\t kh\u00f4ng\t quan\t tr\u1ecdng. \u0110i\u1ec1u\t n\u00e0y,\t nh\u01b0\t \u0111\u00e3\t n\u00f3i,\t l\u00e0\t hi\u1ec3n\t nhi\u00ean,\t v\u00e0\t kh\u00f4ng\t \u0111\u01b0\u1ee3c\t l\u1eabn\t l\u1ed9n\t v\u1edbi t\u00ednh\t ch\u1ea5t\t r\u1ed9ng\t r\u00e3i\t h\u01a1n\t nhi\u1ec1u\t m\u00e0\t ch\u00fang\t ta\t \u0111\u00e3\t g\u1ecdi\t l\u00e0\t \\\"nguy\u00ean\t l\u00fd t\u01b0\u01a1ng\t\u0111\u1ed1i\\\",\tv\u00e0\t\u0111\u00e3\t\u0111\u1eb7t\tn\u00f3\tl\u00e0m\tn\u1ec1n\tt\u1ea3ng\tcho\tnh\u1eefng\tnghi\u00ean\tc\u1ee9u\tc\u1ee7a ch\u00fang\tta. Nguy\u00ean\t l\u00fd\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t ch\u00fang\t ta\t s\u1eed\t d\u1ee5ng\t n\u00f3i\t l\u00ean\t r\u1eb1ng\t ch\u00fang\t ta kh\u00f4ng\t nh\u1eefng\t c\u00f3\t th\u1ec3\t ch\u1ecdn\t xe\t l\u1eeda\t m\u00e0\t c\u00f2n\t [c\u00f3\t th\u1ec3]\t ch\u1ecdn\t n\u1ec1n\t ray nh\u01b0\tv\u1eadt\tth\u1ec3\tquy\tchi\u1ebfu\tcho\tvi\u1ec7c\tm\u00f4\tt\u1ea3\tm\u1ecdi\tdi\u1ec5n\tbi\u1ebfn\tt\u1ef1\tnhi\u00ean\t(b\u1edfi v\u00ec\t \u0111i\u1ec1u\t n\u00e0y\t l\u00e0\t hi\u1ec3n\t nhi\u00ean).\t N\u00f3i\t \u0111\u00fang\t h\u01a1n,\t nguy\u00ean\t l\u00fd\t ch\u00fang\t ta kh\u1eb3ng\t \u0111\u1ecbnh:\t N\u00eau\t ch\u00fang\t ta\t bi\u1ec3u\t th\u1ecb\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1\t nhi\u00ean\t ph\u1ed5 qu\u00e1t,\tnh\u01b0\tch\u00fang\ttho\u00e1t\tthai\tt\u1eeb\tkinh\tnghi\u1ec7m,\tb\u1eb1ng\tc\u00e1ch\tl\u1ea5y","(c)\tXe\tl\u1eeda\tl\u00e0m\tv\u1eadt\tquy\tchi\u1ebfu, (d)\tN\u1ec1n\tray\tl\u00e0m\tv\u1eadt\tquy\tchi\u1ebfu, th\u00ec\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1\t nhi\u00ean\t ph\u1ed5\t qu\u00e1t\t n\u00e0y\t (ch\u1eb3ng\t h\u1ea1n\t c\u00e1c\t \u0111\u1ecbnh lu\u1eadt\t c\u1ee7a\t c\u01a1\t h\u1ecdc,\t hay\t \u0111\u1ecbnh\t lu\u1eadt\t \u00e1nh\t s\u00e1ng\t truy\u1ec1n\t trong\t ch\u00e2n kh\u00f4ng)\tch\u00ednh\tx\u00e1c\tgi\u1ed1ng\tnhau\ttrong\tc\u1ea3\thai\ttr\u01b0\u1eddng\th\u1ee3p.\tCh\u00fang\tta c\u0169ng\tc\u00f3\tth\u1ec3\tbi\u1ec3u\tth\u1ecb\t\u0111i\u1ec1u\tn\u00e0y\tnh\u01b0\tsau:\t\u0110\u1ed1i\tv\u1edbi\ts\u1ef1\tm\u00f4\tt\u1ea3\tv\u1eadt\tl\u00fd\tc\u1ee7a c\u00e1c\t hi\u1ec7n\t t\u01b0\u1ee3ng\t t\u1ef1\t nhi\u00ean,\t kh\u00f4ng\t c\u00e1i\t n\u00e0o\t trong\t c\u00e1c\t v\u1eadt\t th\u1ec3\t quy chi\u1ebfu\tK,\tK\u2019\tn\u1ed5i\ttr\u1ed9i\th\u01a1n\tc\u00e1i\tkia.\tPh\u00e1t\tbi\u1ec3u\tth\u1ee9\thai\tn\u00e0y\tkh\u00f4ng\tnh\u1ea5t thi\u1ebft\t ph\u1ea3i\t \u0111\u00fang\t m\u1ed9t\t c\u00e1ch\t ti\u00ean\t nghi\u1ec7m\t nh\u01b0\t ph\u00e1t\t bi\u1ec3u\t th\u1ee9\t nh\u1ea5t; n\u00f3\tkh\u00f4ng\t\u0111\u01b0\u1ee3c\th\u00e0m\tch\u1ee9a\ttrong\tc\u00e1c\tkh\u00e1i\tni\u1ec7m\t\\\"chuy\u1ec3n\t\u0111\u1ed9ng\\\"\tv\u00e0 \\\"v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\\\"\t ho\u1eb7c\t c\u00f3\t th\u1ec3\t \u0111\u01b0\u1ee3c\t suy\t di\u1ec5n\t t\u1eeb\t ch\u00fang,\t m\u00e0\t ch\u1ec9 c\u00f3\t kinh\t nghi\u1ec7m\t m\u1edbi\t quy\u1ebft\t \u0111\u1ecbnh\t t\u00ednh\t \u0111\u00fang\t \u0111\u1eafn\t hay\t kh\u00f4ng\t \u0111\u00fang \u0111\u1eafn\tc\u1ee7a\tn\u00f3. Tuy\t nhi\u00ean,\t cho\t \u0111\u1ebfn\t nay\t ch\u00fang\t ta\t kh\u00f4ng\t h\u1ec1\t kh\u1eb3ng\t \u0111\u1ecbnh\t t\u00ednh ch\u1ea5t\t t\u01b0\u01a1ng\t \u0111\u01b0\u01a1ng\t c\u1ee7a\t t\u1ea5t\t c\u1ea3\t c\u00e1c\t v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\t K\t li\u00ean\t quan \u0111\u1ebfn\t vi\u1ec7c\t bi\u1ec3u\t th\u1ecb\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1\t nhi\u00ean.\t Con\t \u0111\u01b0\u1eddng\t ch\u00fang\t ta\t \u0111i \u0111\u00fang\t h\u01a1n\t l\u00e0\t nh\u01b0\t th\u1ebf\t n\u00e0y.\t \u0110\u1ea7u\t ti\u00ean\t ch\u00fang\t ta\t \u0111\u00e3\t xu\u1ea5t\t ph\u00e1t\t t\u1eeb\t gi\u1ea3 thuy\u1ebft,\t r\u1eb1ng\t c\u00f3\t m\u1ed9t\t v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\t K\t v\u1edbi\t m\u1ed9t\t tr\u1ea1ng\t th\u00e1i chuy\u1ec3n\t \u0111\u1ed9ng\t sao\t cho\t \u0111\u1ed1i\t v\u1edbi\t n\u00f3\t \u0111\u1ecbnh\t lu\u1eadt\t c\u01a1\t b\u1ea3n\t Galilei\t c\u00f3\t hi\u1ec7u l\u1ef1c:\t M\u1ed9t\t \u0111i\u1ec3m\t kh\u1ed1i\t l\u01b0\u1ee3ng,\t n\u1ebfu\t \u0111\u1ec3\t t\u1ef1\t n\u00f3\t v\u00e0\t \u0111\u1ee7\t xa\t v\u1edbi\t m\u1ecdi\t kh\u1ed1i l\u01b0\u1ee3ng\t c\u00f2n\t l\u1ea1i,\t s\u1ebd\t chuy\u1ec3n\t \u0111\u1ed9ng\t \u0111\u1ec1u\t v\u00e0\t theo\t \u0111\u01b0\u1eddng\t th\u1eb3ng.\t \u0110\u01b0\u1ee3c quy\t chi\u1ebfu\t l\u00ean\t K\t (m\u1ed9t\t v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\t Galilei),\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1 nhi\u00ean\t s\u1ebd\t c\u00f3\t d\u1ea1ng\t \u0111\u01a1n\t gi\u1ea3n\t nh\u01b0\t c\u00f3\t th\u1ec3.\t Nh\u01b0ng,\t ngo\u00e0i\t K\t ra,\t t\u1ea5t\t c\u1ea3 nh\u1eefng\tv\u1eadt\tth\u1ec3\tquy\tchi\u1ebfu\t\u0111\u1ec1u\t\u0111\u01b0\u1ee3c\t\u01b0u\t\u0111\u00e3i\ttheo\tngh\u0129a\tn\u00e0y,\tv\u00e0\t\u0111\u1ec1u t\u01b0\u01a1ng\t \u0111\u01b0\u01a1ng\t v\u1edbi\t K\t trong\t vi\u1ec7c\t bi\u1ec3u\t th\u1ecb\t c\u00e1c\t \u0111\u1ecbnh\t lu\u1eadt\t t\u1ef1\t nhi\u00ean, mi\u1ec5n\tl\u00e0\tch\u00fang\tc\u00f3\tm\u1ed9t\tchuy\u1ec3n\t\u0111\u1ed9ng\tth\u1eb3ng,\t\u0111\u1ec1u,\tv\u00e0\tkh\u00f4ng\tquay\t\u0111\u1ed1i v\u1edbi\tK\u2019,\t t\u1ea5t\t c\u1ea3\t nh\u1eefng\t v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\t n\u00e0y\t \u0111\u1ec1u\t \u0111\u01b0\u1ee3c\t xem\t l\u00e0\t v\u1eadt th\u1ec3\t quy\t chi\u1ebfu\t Galilei.\t Ch\u1ec9\t \u0111\u1ed1i\t v\u1edbi\t c\u00e1c\t v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\t n\u00e0y\t th\u00ec nguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\t\u0111\u01b0\u1ee3c\tgi\u1ea3\t\u0111\u1ecbnh\tc\u00f3\tgi\u00e1\ttr\u1ecb,\tch\u1ee9\tkh\u00f4ng\tph\u1ea3i\t\u0111\u1ed1i v\u1edbi\t c\u00e1c\t v\u1eadt\t th\u1ec3\t quy\t chi\u1ebfu\t kh\u00e1c\t (chuy\u1ec3n\t \u0111\u1ed9ng\t m\u1ed9t\t c\u00e1ch\t kh\u00e1c). Trong\tngh\u0129a\tn\u00e0y,\tch\u00fang\tta\tn\u00f3i\t\u0111\u1ebfn\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p,\thay thuy\u1ebft\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p. Ng\u01b0\u1ee3c\tv\u1edbi\tnh\u1eefng\t\u0111i\u1ec1u\ttr\u00ean,\td\u01b0\u1edbi\tc\u00e1i\tt\u00ean\t\\\"nguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i r\u1ed9ng\\\"\tch\u00fang\tta\tmu\u1ed1n\thi\u1ec3u\tph\u00e1t\tbi\u1ec3u\tsau\t\u0111\u00e2y:\tT\u1ea5t\tc\u1ea3\tv\u1eadt\tth\u1ec3\tquy chi\u1ebfu\t K,\t K\u2019,\t v.v.\t l\u00e0\t t\u01b0\u01a1ng\t \u0111\u01b0\u01a1ng\t nhau\t cho\t vi\u1ec7c\t m\u00f4\t t\u1ea3\t c\u00e1c\t hi\u1ec7n t\u01b0\u1ee3ng\tt\u1ef1\tnhi\u00ean\t(cho\ts\u1ef1\tbi\u1ec3u\tth\u1ecb\tc\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tt\u1ef1\tnhi\u00ean\tph\u1ed5\tqu\u00e1t), b\u1ea5t\t k\u1ec3\t tr\u1ea1ng\t th\u00e1i\t chuy\u1ec3n\t \u0111\u1ed9ng\t c\u1ee7a\t ch\u00fang.\t Tuy\t nhi\u00ean,\t c\u1ea7n\t n\u00f3i","ngay\tr\u1eb1ng,\ts\u1ef1\tbi\u1ec3u\tth\u1ecb\tn\u00e0y\tc\u1ea7n\tph\u1ea3i\t\u0111\u01b0\u1ee3c\tthay\tb\u1eb1ng\tm\u1ed9t\ts\u1ef1\tbi\u1ec3u th\u1ecb\ttr\u1eebu\tt\u01b0\u1ee3ng\th\u01a1n,\tv\u00ec\tnh\u1eefng\tl\u00fd\tdo\tch\u1ec9\thi\u1ec7n\tr\u00f5\tra\t\u1edf\tgiai\t\u0111o\u1ea1n\tsau. Sau\t khi\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t h\u1eb9p\t \u0111\u01b0\u1ee3c\t \u0111\u01b0a\t v\u00e0o\t th\u00e0nh\t c\u00f4ng, nh\u1eefng\t ai\t mu\u1ed1n\t v\u01b0\u01a1n\t t\u1edbi\t s\u1ef1\t kh\u00e1i\t qu\u00e1t\t h\u00f3a\t \u0111\u1ec1u\t c\u1ea3m\t th\u1ea5y\t b\u1ecb\t c\u00e1m d\u1ed7\tmu\u1ed1n\tm\u1ea1o\thi\u1ec3m\t\u0111i\tth\u00eam\tm\u1ed9t\tb\u01b0\u1edbc\tv\u1ec1\th\u01b0\u1edbng\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng \u0111\u1ed1i\t r\u1ed9ng.\t Nh\u01b0ng\t m\u1ed9t\t s\u1ef1\t suy\t ngh\u0129\t \u0111\u01a1n\t gi\u1ea3n,\t c\u00f3\t v\u1ebb\t r\u1ea5t\t \u0111\u00e1ng\t tin, d\u01b0\u1eddng\t nh\u01b0\t cho\t th\u1ea5y\t m\u1ed9t\t n\u1ed7\t l\u1ef1c\t nh\u01b0\t th\u1ebf\t tr\u01b0\u1edbc\t ti\u00ean\t l\u00e0\t v\u00f4\t v\u1ecdng. B\u1ea1n\t \u0111\u1ecdc\t h\u00e3y\t h\u00ecnh\t dung\t \u0111\u1eb7t\t m\u00ecnh\t v\u00e0o\t chi\u1ebfc\t xe\t l\u1eeda\t ch\u1ea1y\t v\u1edbi\t v\u1eadn t\u1ed1c\t \u0111\u1ec1u\t \u0111\u00e3\t \u0111\u01b0\u1ee3c\t nhi\u1ec1u\t l\u1ea7n\t xem\t x\u00e9t.\t Bao\t l\u00e2u\t xe\t ch\u1ea1y\t \u0111\u1ec1u,\t ng\u01b0\u1eddi h\u00e0nh\tkh\u00e1ch\ts\u1ebd\tkh\u00f4ng\th\u1ec1\tc\u1ea3m\tnh\u1eadn\tg\u00ec\tv\u1ec1\ts\u1ef1\tdi\tchuy\u1ec3n\tc\u1ee7a\txe.\tCho n\u00ean\t h\u1ec7\t qu\u1ea3\t l\u00e0\t anh\t ta\t c\u0169ng\t c\u00f3\t th\u1ec3\t di\u1ec5n\t gi\u1ea3i\t b\u1ea3n\t ch\u1ea5t\t s\u1ef1\t vi\u1ec7c\t theo h\u01b0\u1edbng\t sau\t \u0111\u00e2y\t m\u00e0\t kh\u00f4ng\t g\u1eb7p\t ph\u1ea3i\t s\u1ef1\t kh\u00e1ng\t c\u1ef1\t n\u1ed9i\t t\u00e2m,\t r\u1eb1ng chi\u1ebfc\t xe\t \u0111\u1ee9ng\t y\u00ean\t trong\t khi\t n\u1ec1n\t ray\t \u0111ang\t ch\u1ea1y.\t C\u00e1ch\t di\u1ec5n\t gi\u1ea3i n\u00e0y\tth\u1ef1c\tra,\ttheo\tnguy\u00ean\tl\u00fd\tt\u01b0\u01a1ng\t\u0111\u1ed1i\th\u1eb9p,\tc\u0169ng\tho\u00e0n\tto\u00e0n\tch\u00ednh \u0111\u00e1ng\tv\u1ec1\tm\u1eb7t\tv\u1eadt\tl\u00fd\th\u1ecdc. Tuy\tnhi\u00ean\tn\u1ebfu\tb\u00e2y\tgi\u1edd\tchuy\u1ec3n\t\u0111\u1ed9ng\tc\u1ee7a\txe\tl\u1eeda\tbi\u1ebfn\tth\u00e0nh\tm\u1ed9t chuy\u1ec3n\t\u0111\u1ed9ng\tkh\u00f4ng\t\u0111\u1ec1u,\tch\u1eb3ng\th\u1ea1n\tnh\u01b0\tkhi\txe\tl\u1eeda\tth\u1eafng\tm\u1ea1nh, l\u00fac\t\u0111\u00f3\tng\u01b0\u1eddi\th\u00e0nh\tkh\u00e1ch\tb\u1ecb\tm\u1ed9t\tl\u1ef1c\t\u0111\u1ea9y\tk\u00e9o\tm\u1ea1nh\tv\u1ec1\tph\u00eda\ttr\u01b0\u1edbc. Chuy\u1ec3n\t \u0111\u1ed9ng\t b\u1ecb\t h\u00e3m\t l\u1ea1i\t \u0111\u01b0\u1ee3c\t th\u1ec3\t hi\u1ec7n\t qua\t s\u1ef1\t v\u1eadn\t h\u00e0nh\t c\u01a1\t h\u1ecdc c\u1ee7a\t c\u00e1c\t v\u1eadt\t th\u1ec3\t trong\t xe\t \u0111\u1ed1i\t v\u1edbi\t anh\t ta;\t s\u1ef1\t v\u1eadn\t h\u00e0nh\t c\u01a1\t h\u1ecdc\t l\u00e0 kh\u00e1c\th\u01a1n\ts\u1ef1\tv\u1eadn\th\u00e0nh\ttrong\ttr\u01b0\u1eddng\th\u1ee3p\t\u0111\u00e3\tx\u00e9t\ttr\u01b0\u1edbc\t\u0111\u00f3,\tv\u00e0\tc\u00f3\tl\u1ebd v\u00ec\tth\u1ebf\tm\u00e0\tkh\u00f4ng\tth\u1ec3\tn\u00e0o\tc\u00e1c\t\u0111\u1ecbnh\tlu\u1eadt\tc\u01a1\th\u1ecdc\t\u0111\u1ed1i\tv\u1edbi\tm\u1ed9t\tchi\u1ebfc\txe ch\u1ea1y\t kh\u00f4ng\t \u0111\u1ec1u\t nh\u01b0\t th\u1ebf\t c\u0169ng\t \u0111\u00fang\t nh\u01b0\t ch\u00fang\t \u0111\u00e3\t \u0111\u00fang\t \u0111\u1ed1i\t v\u1edbi chi\u1ebfc\txe\tch\u1ea1y\t\u0111\u1ec1u,\thay\t\u0111\u1ee9ng\ty\u00ean.\tTrong\tm\u1ecdi\tt\u00ecnh\thu\u1ed1ng,\tr\u00f5\tr\u00e0ng \u0111\u1ecbnh\tlu\u1eadt\tc\u01a1\tb\u1ea3n\tGalilei\tkh\u00f4ng\tc\u00f2n\t\u0111\u00fang\t\u0111\u1ed1i\tv\u1edbi\tchi\u1ebfc\txe\tchuy\u1ec3n \u0111\u1ed9ng\t kh\u00f4ng\t \u0111\u1ec1u.\t V\u00ec\t l\u00fd\t do\t n\u00e0y,\t ch\u00fang\t ta\t tr\u01b0\u1edbc\t m\u1eaft\t c\u1ea3m\t th\u1ea5y\t b\u1ecb b\u1eaft\t bu\u1ed9c\t ph\u1ea3i\t c\u00f4ng\t nh\u1eadn\t m\u1ed9t\t lo\u1ea1i\t th\u1ef1c\t t\u1ea1i\t v\u1eadt\t l\u00fd\t tuy\u1ec7t\t \u0111\u1ed1i\t cho chuy\u1ec3n\t \u0111\u1ed9ng\t kh\u00f4ng\t \u0111\u1ec1u,\t ng\u01b0\u1ee3c\t v\u1edbi\t nguy\u00ean\t l\u00fd\t t\u01b0\u01a1ng\t \u0111\u1ed1i\t r\u1ed9ng. Tuy\tnhi\u00ean,\td\u01b0\u1edbi\t\u0111\u00e2y\tch\u00fang\tta\ts\u1ebd\tnhanh\tch\u00f3ng\tth\u1ea5y\tr\u1eb1ng\tk\u1ebft\tlu\u1eadn n\u00e0y\tkh\u00f4ng\t\u0111\u1ee9ng\tv\u1eefng."]