Impact of inhomogeneities on slowly rolling quintessence: implications for the local variations of the fine-structure constant
Abstract
We study how the evolution of a dark energy quintessence fluid is modified by the presence of a matter inhomogeneity. To do so, we study linear perturbations of a flat FLRW background containing dust and a slowly rolling scalar field. Under the assumptions of spherical symmetry and a static density contrast, i.e. $\dot {\delta }=0$, we obtain simple analytical solutions for perturbations in the matter and dark energy-dominated epochs. As a consequence, we show that perturbations of the scalar field, if a coupling à la Bekenstein is assumed, trigger a spatial dependence of the fine-structure 'constant' which then varies as Δα ∝ 1/r. We finally highlight that such variations can be constrained with spectroscopic observations of stars from within our galaxy, therefore offering a new probe of the nature of dark renergy.
- Publication:
-
Classical and Quantum Gravity
- Pub Date:
- August 2021
- DOI:
- 10.1088/1361-6382/ac1870
- arXiv:
- arXiv:2102.11735
- Bibcode:
- 2021CQGra..38q5010G
- Keywords:
-
- quintessence;
- dark energy;
- varying α;
- General Relativity and Quantum Cosmology;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- v2, with minor changes to match the published version. 2 tables and 1 figure added, with a discussion of current observations