Lessons from Stuekelberg theory in Cosmology.

Abstract: Stueckelberg solved the problem of gauge invariance in massive QED by a new mechanism which is precursor for Abelian Higgs. It has several implications in Cosmology and we will discuss few of them. Strong electromagnetic and gravitational field physics: From laboratories to early Universe / 214 A study of scalar quantum electrodynamics in de Sitter spacetime Department of Physics, University of Kashan, 8731753153, Kashan, Iran The aim of this study is to explore some features of the nonperturbative, one-loop, regularized effective Lagrangian of scalar quantum electrodynamics (QED) in a uniform electric field background with constant energy density in the Poincare patch of 2-dimensional de Sitter spacetime (dS2). Particularly, the electric permittivity of the vacuum, and the equation of state of the created Schwinger scalars have been investigated.