早期宇宙反饋作用之探索

The origin of the observed large-scale cosmic magnetic fields remains elusive. Although various possibilities have been under investigation, the generation of primordial magnetic fields (PMF) during inflation is arguably the most appealing mechanism among them. The conformal symmetry of the electromagnetic field may easily be broken via their helical or non- helical coupling to an inflaton field. However, the efficiency of producing primordial magnetic seed fields in such settings is still in doubts. We propose to illuminate the inflationary magnetogenesis by virtue of the backreaction mechanism during cosmic inflation. Employing the Higgs Inflation as the workhorse, we find that the backaction terms indeed change the electromagnetic behavior of the inflaton field, the strong redshift caused by the inflation suppresses the grow of the PMF. In other words, wee need to either changing the constraints on the back reaction mechanism or adding additional interactions to surmount the barrier of growing PMF.