Bumpy inflation from explosive particle production

Kaloian D. Lozanov; Xavier Pritchard; Misao Sasaki

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arXiv · 2608.26920

Bumpy inflation from explosive particle production

Kaloian D. Lozanov·Xavier Pritchard·Misao Sasaki

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Abstract

We present a first-principles derivation of an effective inflaton potential with a bumpy feature. We consider the coupling of a spectator field \chi to the inflaton \phi such that \chi is massive enough for almost all values of \phi, but becomes massless when the inflaton crossed the value \phi_\star. This gives rise to a burst of \chi-particle production at \phi=\phi_\star. By taking the backreaction of the particle production, we obtain a bumpy feature in the effective potential.

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Kaloian D. Lozanov, Xavier Pritchard, Misao Sasaki. 2026-08-27. Bumpy inflation from explosive particle production. https://arxiv.org/abs/2608.26920

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