【摘 要】
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One of the key questions of modern physics concerns the possibility that physical constants vary over space and time during the history of the universe.The Standard Model of physics is built on these
【出 处】
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国际天文学联合会第312次专题会议
论文部分内容阅读
One of the key questions of modern physics concerns the possibility that physical constants vary over space and time during the history of the universe.The Standard Model of physics is built on these constants,but it does not provide an explanation for their values,nor requires their constancy over space and time.Here we set a new limit on possible spatial and temporal variations of the fine-structure constant α=e2/(4πε0(h)c),by comparing fine splitting transitions in [NeⅢ],[NeV],[OⅢ],[OI] and [SⅡ] multiplets observed in the early universe with those measured in the laboratory.Based on optical spectra observations of 14 Seyfert 1.5 galaxies in the low-z range 0.035 < z < 0.281,we deduced a constraint of △α/α=(-4.50±5.53)×10-4.This is at present the tightest limit on △α/α at early cosmological epochs.
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