Running non-minimal inflation with stabilized inflaton potential

Abstract

In the context of the Higgs model involving gauge and Yukawa interactions with the spontaneous gauge symmetry breaking, we consider λφ 4 inflation with nonminimal gravitational coupling, where the Higgs field is identified as the inflaton. Since the inflaton quartic coupling is very small, once quantum corrections through the gauge and Yukawa interactions are taken into account, the inflaton effective potential most likely becomes unstable. In order to avoid this problem, we need to impose stability conditions on the effective inflaton potential, which lead to not only non-trivial relations amongst the particle mass spectrum of the model, but also correlations between the inflationary predictions and the mass spectrum. For concrete discussion, we investigate the minimal B − L extension of the standard model with identification of the B − L Higgs field as the inflaton. The stability conditions for the inflaton effective potential fix the mass ratio amongst the B − L gauge boson, the right-handed neutrinos and the inflaton. This mass ratio also correlates with the inflationary predictions. In other words, if the B − L gauge boson and the right-handed neutrinos are discovered in the future, their observed mass ratio provides constraints on the inflationary predictions.

Non-minimal CW inflation, electroweak symmetry breaking and the 750 GeV anomaly

“…In the following we will implicitly assume these features referring the reader to [19] for further details. We also remark, that similar models of CW inflation were studied in [26,27], involving a U (1) B−L gauge group and leading to results in line with ours.…”

Impact of new physics on the EW vacuum stability in a curved spacetime background

“…Clearly the goal is no longer to derive bounds on its mass, but rather to perform more refined analyses that should allow to discriminate between absolute stability or metastability for the EW vacuum [18][19][20][21], to study the cosmological impact of the vacuum stability condition during and after inflation [22][23][24][25][26][27][28][29][30][31][32], and to test the impact that different NP scenarios can have on the vacuum stability condition [18,[33][34][35][36][37][38][39][40][41][42][43][44]. This renewed interest also prompted a more careful treatment of issues as the gauge invariance of the vacuum decay rate and the contribution of zero modes to the quantum fluctuation determinant [45][46][47][48][49][50].…”

Running Non-Minimal Inflation with Stabilized Inflation Potential

“…Then, we consider the RG improved effective inflaton potential by taking into account the RG evolution of the quartic coupling with the initial condition at φ I . The inflaton quartic coupling is very small unless ξ 1 (see [1] for details). Hence the beta function of the quartic coupling is approximately given by…”

“…Hence, quantum corrections to the effective potential are dominated by the gauge and Yukawa interactions. We consider the renormalization group (RG) improved effective potential described as V (φ ) = 1 4 λ (φ ) φ 4 , where φ denotes inflaton, and λ (φ ) is the running quartic coupling satisfying the (one-loop) RG equation of the form,…”