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arXiv · 2202.10871

Dynamical system analysis of Myrzakulov gravity

G. Papagiannopoulos·Spyros Basilakos·Emmanuel N. Saridakis
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Abstract

We perform a dynamical system analysis of Myrzakulov or F(R, T) gravity, which is a subclass of affinely connected metric theories, where ones uses a specific but non-special connection, which allows for non-zero curvature and torsion simultaneously. We consider two classes of models, we extract the critical points, and we examine their stability properties alongside their physical features. In the Class 1 models, which possess ΛCDM cosmology as a limit, we find the sequence of matter and dark energy eras, and we show that the Universe will result in a dark-energy dominated critical point for which dark energy behaves like a cosmological constant. Concerning the dark-energy equation-of-state parameter we find that it lies in the quintessence or phantom regime, according to the value of the model parameter. For the Class 2 models, we again find the dark-energy dominated, de Sitter late-time attractor, although the scenario does not possess ΛCDM cosmology as a limit. The cosmological behavior is richer, and the dark-energy sector can be quintessence-like, phantom-like, or experience the phantom-divide crossing during the evolution.

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G. Papagiannopoulos, Spyros Basilakos, Emmanuel N. Saridakis. 2022-10-19. Dynamical system analysis of Myrzakulov gravity. https://doi.org/10.1103/physrevd.106.103512

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