Speaker
Hexu Zhang
Description
Classically conformal theories provide a compelling framework for dynamical scale generation in the early Universe. In this talk, I show that classically conformal cosmology can naturally produce primordial black hole dark matter through two distinct mechanisms: delayed vacuum phase transitions in ultra-supercooled first-order phase transitions and tachyonic amplification of curvature perturbations during thermal inflation. I also discuss the graceful-exit problem of conformal thermal inflation and demonstrate how fermion condensation can naturally terminate eternal inflation. The resulting scenarios predict rich phenomenology, including primordial black holes and gravitational-wave signals.