Clocking the fundamental physical constants

Publisher Website
Google Scholar
Abstract
The term "fundamental physical constants" invites two questions: are they fundamental, and are they constant? The non-trivial problem for the second question, which we consider here, is to find something of assured constancy to serve as a reference. One soon realizes that it is most meaningful to concentrate on dimensionless quantities such as the ratio of the electron to proton mass (mc/mp), the fine structure constant (α) and gyromagnetic ratios. Laboratory comparisons of present-day clocks – such as the recent comparison of magnesium and caesium clocks at the Istituto Elettrotecnico Nazionale Galileo Ferraris in Turin (A Godone et al. Phys. Rev. Lett. (1993) 71 2364) – are increasingly able to test the constancy of these ratios. Tests can achieve precisions of possible cosmological significance and there are prospects for more stringent tests in the future.

This publication has 0 references indexed in Scilit: