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arXiv · 2606.03408

Models of exponential and power-law acceleration of the Universe in Horndeski theory without ghosts and Laplace instabilities

Ruslan K. Muharlyamov·Tatiana N. Pankratyeva·Shehabaldeen O. A. Bashir
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Abstract

We present a designer method for flat Friedman-Robertson-Walker space-times within the framework of Horndeski's scalar-tensor theory. As a result, one can find subclasses of Horndeski's scalar-tensor theory within which cosmological solutions exist without ghosts and Laplace instabilities. As an example, we found subclasses of Horndeski's theory for exponential and power-law inflation models of the Universe without pathologies.

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Ruslan K. Muharlyamov, Tatiana N. Pankratyeva, Shehabaldeen O. A. Bashir. 2026-06-02. Models of exponential and power-law acceleration of the Universe in Horndeski theory without ghosts and Laplace instabilities. https://arxiv.org/abs/2606.03408

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