Praveen Kumar
LAM, U. Aix-Marseille

Abstract
Searching for space-time variations of the constants of Nature is a promising way to look for new physics beyond General Relativity and the standard model motivated by unification theories and models of dark matter and dark energy. Astrophysical tests of the stability of dimensionless fundamental constants (such as the fine-structure constant) are a powerful probe of cosmology as well as of fundamental physics. Recently these measurements, combined with astrophysical data and local atomic clock tests, were used to constrain the simplest class of dynamical dark energy models through a dimensionless coupling to the electromagnetic sector as we know. (In realistic dynamical dark energy models the dynamical degree of freedom is expected to couple to the electromagnetic sector, leading to variations of alpha.) One of the main challenges of modern cosmology is to investigate the nature of dark energy, which is seemingly behind the recent acceleration of the universe. Updating the Chevallier-Polarski-Linder (CPL) parametrization model of dark energy equation of state with the recent measurements as mentioned above is the objective of this thesis. The availability of more precise measurements, one can do a systematic analysis of the cosmology and fundamental physics constraints implied by these tests is what made me pursue this internship.

2020 July 02, 13:45

IA
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