Probing unification scenarios with atomic clocks

We discuss the usage of measurements of the stability of nature’s fundamental constants coming from comparisons between atomic clocks as a means to constrain coupled variations of these constants in a broad class of unification scenarios. After introducing the phenomenology of these models, we provide updated constraints based on a global...

A test of unification towards the radio source PKS1413+135

We point out that existing astrophysical measurements of combinations of the fine-structure constant ?, the proton-to-electron mass ratio ? and the proton gyromagnetic ratio gpgp towards the radio source PKS1413+135 can be used to individually constrain each of these fundamental couplings. While the accuracy of the available measurements is not...