Varying finestructure constant cosmography
Abstract
Cosmography is a phenomenological and relatively modelindependent approach to cosmology, where physical quantities are expanded as a Taylor series in the cosmological redshift, or in related variables. Here we apply this methodology to constrain possible cosmological variations of the finestructure constant, α. Two peculiarities of this case are the existence of highredshift data, and the fact that one term in the series is directly and tightly constraint by local laboratory tests with atomic clocks. We use this atomic clock data, together with direct modelindependent highresolution astrophysical spectroscopy measurements of α up to redshift z ∼ 7 and additional modeldependent constraints on α from the cosmic microwave background and big bang nucleosynthesis, to place stringent (parts per million level) constraints on the first two terms in the α cosmographic series.
 Publication:

Physics Letters B
 Pub Date:
 April 2022
 DOI:
 10.1016/j.physletb.2022.137002
 arXiv:
 arXiv:2203.02781
 Bibcode:
 2022PhLB..82737002M
 Keywords:

 Cosmology;
 Cosmography;
 Varying fundamental constants;
 Finestructure constant;
 Atomic clocks;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology
 EPrint:
 10 pages, 3 figures, 2 tables. Phys. Lett. B (in press)