Hannover 2010 – scientific programme

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SYFC: Symposium Variations of Fundamental Constants: Theory and Experiment

SYFC 2: Variations of Fundamental Constants II

SYFC 2.1: Invited Talk

Monday, March 8, 2010, 16:30–17:00, A 001

Gravitational and cosmological probes of varying fundamental parameters — •Thomas Dent — Cardiff University

If fundamental parameters of physics such as gauge couplings and particle masses (mass ratios) vary over spacetime then the equivalence principles and framework of general relativity must be altered. As one result, test objects of different composition do not feel the same acceleration: hence local variations can be tested by Eötvös experiments. This provides the strongest bound on variations within the Solar System tracking the gravitational potential.

For physical consistency, an extra degree of freedom is required to exist as a cause of variation. If there is a cosmological time variation such a field will contribute to the expansion of the Universe via its stress-energy. This contribution can be bounded by probes of 'dark energy', putting interesting bounds on the magnitude of time variation in different scenarios.