On stochastic effects and primordial black-hole formation

Abstract The effect of large quantum fluctuations on primordial black-hole formation for inflationary models with a quasi-inflection point is investigated. By using techniques of stochastic inflation in combination with replica field theory and the Feynman–Jensen variational method, it is non-perturbatively demonstrated that the abundance of primordial black holes is amplified by several orders of magnitude as compared to the classical computation.