Speaker
Description
We investigate inflationary magnetogenesis considering massive electromagnetic fields, including scalar particle production via the Schwinger effect and the backreaction induced on the background electric energy density. As long as the Schwinger effect is neglected, we fully quantize the electromagnetic field and solve the equations of motion for transverse and longitudinal modes, computing the related contributions to the energy density from the energy-momentum tensor. In the calculations, we account also for the backreaction of the electric energy density. We prove that masses compatible with experimental constraints do not significantly modify the equations, and the longitudinal energy density is subleading compared to the electric background. In addition, the electric energy density turns out to be dominant over the magnetic one, uniquely as a consequence of the homogeneity and isotropy of the spacetime fabric. In view of this, we can treat the electric background separately from the perturbative contributions. We adopt this approach when studying particle production via the Schwinger effect, considering that the backreaction affects only the background electric energy density. Accordingly, the latter is computed considering a classical background electromagnetic field coupled to a quantum complex scalar field through a minimal coupling. Separately, the magnetic and longitudinal components are still described through quantum fields. In this framework, the Schwinger production affects only the electric energy density, as long as it remains dominant compared to the other components. For the sake of consistency, we check that for a null coupling constant we recover the same electric energy density as obtained considering a quantum electromagnetic field. Finally, we show that for non-null coupling constants the Schwinger particle production drastically reduces the electric energy density in the final stages of inflation.