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arXiv · 2403.02623

Stability investigations of de Sitter inflationary solutions in power-law extensions of the Starobinsky model

Tuyen M. Pham·Duy H. Nguyen·Tuan Q. Do·W. F. Kao
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Abstract

In this paper, we would like to examine whether stable de Sitter inflationary solutions appear within power-law extensions of the Starobinsky model. In particular, we will address general constraints for the existence along with the stability of de Sitter inflationary solutions in a general case involving not only the Starobinsky $R^2$ term but also an additional power-law $R^n$ one. According to the obtained results, we will be able to identify which extension is more suitable for an early inflationary phase rather than a late-time cosmic acceleration phase. To be more specific, we will consider several values of $n$ to see whether the corresponding de Sitter inflationary solutions are stable or not.

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Tuyen M. Pham, Duy H. Nguyen, Tuan Q. Do, W. F. Kao. 2024-03-05. Stability investigations of de Sitter inflationary solutions in power-law extensions of the Starobinsky model. https://doi.org/10.1140/epjc%2Fs10052-024-13083-z

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