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تسجيل مستخدم جديدThe Fundamental Constants in Physics and their Time Dependence
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تأليف
Harald Fritzsch
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We discuss the fundamemtal 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 variation of the finestructure constant alpha and the QCD scale $Lambda_c$. The astrophysical observation of a variation implies a time variation of $10^{-15} / year$. Several experiments in Quantum Optics, which were designed to look for a time variation of $Lambda_c$, are discussed.
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We discuss the fundamental constants of physics in the Standard Model and possible changes of these constants on the cosmological time scale. The Grand Unification of the strong, electromagnetic and weak interactions implies relations between the tim
e variation of the finestructure constant and of the QCD scale. An experiment in quantum optics at the MPQ in Munich, which was designed to look for a time variation of the QCD scale, is discussed.
A new method for measuring a possible time dependence of the fine-structure constant ($alpha$) is proposed. The method is based on the level-crossing in two-electron highly-charged ions facilitating resonance laser measurements of the distance betwee
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m Expectation Value and the Yukawa couplings. Further model dependent assumptions provide constraints on the Higgs VEV and the Yukawa couplings separately. A primary conclusion is that limits on the variability of dimensionless fundamental constants such as $mu$ and $alpha$ provide important constraints on the parameter space of new physics and cosmologies.
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