| Speaker: | Jinglong Liu (Shanghai Jiao Tong U) |
|---|---|
| Title: | Fermion condensate inflation with waterfall mechanism |
| Date (JST): | Tue, Mar 31, 2026, 13:30 - 15:00 |
| Place: | Seminar Room A |
| Abstract: |
Fermion condensate inflation, driven by spacetime torsion-induced four-fermion interactions, provides an inflationary mechanism without requiring fundamental scalar fields beyond the Standard Model. In this framework, the fermion field decomposes into two distinct sectors that generate bound states. Upon integrating out the fermionic degrees of freedom, these bound fields act as the inflaton and a waterfall field, naturally realizing a hybrid inflation scenario. Furthermore, the inclusion of an axial chemical potential dictates the termination of the reheating phase. We show that during the waterfall transition, the effective potential of the fermion condensate allows for the formation of non-topological solitons, or $Q$-balls, which serve as seeds for primordial black holes (PBHs). Deeply connected to Chern-Simons gravity and the damping of gravitational waves by self-interacting fermions, this model yields distinct, testable predictions for PBH dark matter abundance and stochastic gravitational-wave signatures. |
