Revisiting the energy-momentum squared gravity

Mihai Marciu

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arXiv · 2601.22333

Revisiting the energy-momentum squared gravity

Mihai Marciu

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Abstract

In this paper we have revisited the energy-momentum squared gravity theory, by taking into account the second derivative of the matter Lagrangian with respect to the metric, encapsulating relations originated from thermodynamical grounds. After obtaining the scalar tensor representation of the energy-momentum squared gravity with the new corrections, we have analyzed the physical implications by relying on the linear stability theory. The results show that the current cosmological system is compatible with the expansion of the Universe for some specific matter Lagrangians, explaining the emergence of matter domination era, approaching the late time accelerated expansion era close to the de-Sitter phenomenology.

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Mihai Marciu. 2026-01-29. Revisiting the energy-momentum squared gravity. https://arxiv.org/abs/2601.22333

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