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arXiv · 2304.04065

Galileon inflation evades the no-go for PBH formation in the single-field framework

Sayantan Choudhury·Sudhakar Panda·M. Sami
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Abstract

We consider Galileon inflation in the Effective Field Theory (EFT) framework and examine the possibility for PBH formation during slow roll (SR) to ultra slow roll (USR) transitions. We show that loop corrections to the power spectrum, in this case, do not impose additional constraints on the masses of PBHs produced. We indicate that the remarkable non-renormalization property of Galileans due to generalized shift symmetry dubbed as Galilean symmetry is responsible for protecting PBH formation from quantum loop corrections.

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Sayantan Choudhury, Sudhakar Panda, M. Sami. 2023-04-08. Galileon inflation evades the no-go for PBH formation in the single-field framework. https://doi.org/10.1088/1475-7516%2F2023%2F08%2F078

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