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arXiv · 2606.10485

Natural Inflation with a negative cosmological constant

Chia-Min Lin·Naoto Maki·Kazunori Kohri
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Abstract

In this work, we investigate a cosmic inflation model based on a cosine-type potential with a negative cosmological constant. This model originates from a classical solution of the Wheeler-DeWitt equation. The equation of motion for the inflaton field can be solved analytically without relying on approximation schemes, such as the slow-roll conditions. The predictions of the spectral index, the tensor-to-scalar ratio, and the running spectral index are calculated and compared with experimental constraints from Planck Collaboration, Atacama Cosmology Telescope Collaboration (ACT), and Dark Energy Spectroscopic Instrument (DESI).

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Chia-Min Lin, Naoto Maki, Kazunori Kohri. 2026-06-09. Natural Inflation with a negative cosmological constant. https://arxiv.org/abs/2606.10485

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