The Fundamental Constants in Physics and their Time Dependence
نویسنده
چکیده
We discuss the fundamental constants in the Standard Model of particle physics, in particular possible changes of these constants on the cosmological time scale. The Grand Unification of the observed strong, electromagnetic and weak interactions implies relations between time variations of the finestructure constant α and the QCD scale Λc. The astrophysical observation of a variation of α implies a time variation of Λc of the order of at least 10 /year. Several experiments in Quantum Optics, which were designed to look for a time variation of Λc, are discussed.
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