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arXiv · 2506.15965

Smooth hybrid inflation in light of ACT DR6 data

Nobuchika Okada·Osamu Seto
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Abstract

Smooth hybrid inflation is a hybrid inflation model which is free from topological defects and predicts the density perturbation with the spectral index of about $0.97$. We show that the prediction on the spectral index is robust regardless the power of nonrenormalizable terms and meets with the latest results reported by Atacama Cosmology Telescope. Viable scenarios for baryogenesis and dark matter are also discussed.

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Nobuchika Okada, Osamu Seto. 2025-06-19. Smooth hybrid inflation in light of ACT DR6 data. https://doi.org/10.1103/y9s8-7b5b

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