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arXiv · 2609.32572

Bimodal mass primordial black holes in three-field inflation

M. M. Nasrolahzadeh·N. Khosravi
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Abstract

In this paper, we study the evolution of curvature and entropy perturbations in three-field inflation with non-canonical kinetic terms. Using the kinematic basis in field space, we characterize the background trajectory through its turning rate and non-planar torsion. We also emphasize the inherited structure of perturbations from the kinematic system, which detaches the distinct roles of turning rate and torsion in the interactions among perturbations. We present and study numerically a three-phase model with an intermediate decelerated expansion stage in which two separated transient epochs amplify two distinct families of modes, generating a double-peaked curvature power spectrum. This double-peaked power spectrum leads to the formation of primordial black holes with two characteristic masses, $M_1\sim2\times10^{-12}M_\odot$ and $M_2\sim52M_\odot$ explaining, simultaneously, both dark matter and the LIGO-Virgo-KAGRA binary black hole mass range.

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M. M. Nasrolahzadeh, N. Khosravi. 2026-09-26. Bimodal mass primordial black holes in three-field inflation. https://arxiv.org/abs/2609.32572

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