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arXiv · 2401.12040

Construction of Chiral Cosmological Models Unifying Inflation and Primordial Black Hole Formation

Ekaterina O. Pozdeeva·Sergey Yu. Vernov
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Abstract

We propose the method for construction of $F(R,\xi)$ gravity model, unifying inflation and primordial black hole formation. The proposed models are based on the Starobinsky $R+R^2$ inflationary model, so, the function $F(R,\xi)$ is a quadratic polynomial of the Ricci scalar $R$. We show that the potential of the corresponding two-field chiral cosmological model in the Einstein frame can be always found in terms of the elementary functions. The special choice of the function $F(R,\xi)$ allows us to get such a generalization of the hybrid inflation that can describe both inflation, and the primordial black hole formation.

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Ekaterina O. Pozdeeva, Sergey Yu. Vernov. 2024-01-22. Construction of Chiral Cosmological Models Unifying Inflation and Primordial Black Hole Formation. https://doi.org/10.17238/issn2226-8812.2024.1.90-94

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