New cosmological constraints on the variation of fundamental constants: the fine structure constant and the Higgs vacuum expectation value

¹ Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque, 1900 La Plata, Argentina
e-mail: osvaldo.civitarese@fisica.unlp.edu.ar
² Department of Physics, University of La Plata c.c. 67, 1900 La Plata, Argentina

Received: 23 October 2012
Accepted: 5 January 2013

Abstract

Aims. We study the time variation of the fine structure constant, α, and the Higgs vacuum expectation value v, during the Big Bang nucleosynthesis (BBN).

Methods. We computed primordial abundances of light nuclei produced during the BBN stage by including resonances in the leading reaction rates which reduce the primordial abundance of beryllium. We performed this calculation considering that α and v may vary during the BBN. Using observable data on deuterium, ⁴He, and ⁷Li, we set constraints on the variation of the fundamental constants.

Results. Results indicate a null variation of α and v, while the best-fit value for the baryon-to-photon ratio agrees well with the WMAP value.

Conclusions. We found that the variation of α is null within 3σ, the variation of v is null within 6σ, and the preferred value of the baryon-to-photon ratio is in good agreement, within 3σ, with the value extracted using the WMAP data. We improve the fits respect to previous works.