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arXiv · 2506.08489

Behaviour of $α$-attractors in Warm Inflation

Abstract

The $α$-attractor models of inflation have remained one of the preferred inflationary models for nearly a decade now. The unique attractor nature of these models in the $n_s-r$ plane have put these models in the sweet-spot of the $n_s-r$ measurement of Planck observations. In this article, we analyse the behaviour of such attractor models in a Warm Inflation setup to investigate whether the attractor nature of these models can be retained even when the dynamics deviates from the standard Cold inflationary dynamics. We have chosen to analyse these models in a strongly dissipative Warm inflation setup, namely the Minimal Warm Inflation, as in such a setup the inflationary dynamics significantly departs from the standard Cold inflation dynamics. We observe that the departure from the standard Cold inflation dynamics destroys the unique attractor nature of such models. The analysis clearly indicates that the attractor nature of these $α$-attractor models is quite unique to the standard Cold inflationary dynamics. However, on a positive note, the analysis indicates that the $α$-attractor models may be made in tune with the recent ACT results in Warm inflation for certain parameter ranges.

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Dibya Chakraborty, Suratna Das. 2025-09-03. Behaviour of $α$-attractors in Warm Inflation. https://arxiv.org/abs/2506.08489

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