By considering a warm inflaton model, Piccinelli and Sanchez carried out study on the effects of a magnetic field on the inflation’s potential. They found that the effect of the magnetic field on the effective potential is to make it less steep, preserving the slow-roll conditions. Their study recently appeared in Arxiv.
Magnetic fields are present at all scales in the universe. It seems probable that these fields should be present at all times, during the universe evolution. Thus, it is important to consider effects of magnetic field if you are addressing some early universe events. In particular, if magnetic field has to play any role in inflationary process, one must have to consider dissipative processes. This could happen in models where inflaton is coupled to gauge fields, to supersymmetric light fields, as in models of trapped inflation or to heavy ones, as in warm inflation.
Piccinelli and Sanchez considered warm inflation model, where the inflaton is assumed to interact with other fields, both during the inflationary expansion as well as at reheating, in a continuous and more natural way. It is a model where (near) thermal equilibrium conditions are maintained during the inflationary expansion, with no need for very flat potentials, nor for a tiny coupling constant. The model is based on global supersymmetry and a coupling between the inflaton and heavy intermediate superfields which are in turn coupled to light particles.
“Previously, we explored the effect of a weak magnetic field on the warm inflation effective potential, up to one loop, for neutral heavy bosons interacting with the charged light sector and showed that the magnetic field makes the potential flatter, retarding the transition, and works as an additional SUSY breaking scale. In this paper, we broaden the scenario, allowing for magnetic fields of arbitrary strength and charged heavy fields.”
They found that the effect of magnetic field on the effective potential is to make it less steep as compared with the vacuum case, showing that magnetic fields do not spoil the inflationary process.
“This result could be relevant in order to continue exploring the role played by magnetic fields on cosmological events, since there are good chances that they were present during the early stages of the universe, where phase transitions provided suitable conditions for their generation.”, concluded authors of the study.
References: (1) Gabriella Piccinelli, Angel Sanchez, “Magnetic warm inflation”, Arxiv, pp. 1-13, 2021.
arXiv:2106.14791 (2) Gabriella Piccinelli, Ángel Sánchez, Alejandro Ayala, and Ana Julia Mizher, “Warm inflation in the presence of magnetic fields”, Phys. Rev. D 90, 083504 – Published 3 October 2014.
Note for editors of other websites: To reuse this article fully or partially kindly give credit either to our author/editor S. Aman or provide a link of our article