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arXiv · 2203.12358

Dynamical Dark Energy in Minimally Modified Gravity

Alexander Ganz
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Abstract

Minimally modified gravity is a class of models with only the two tensor degrees of freedom as in general relativity. Using the framework with auxiliary constraints these models can maintain a dynamical cosmological background. The form of the constraints is thereby restricted by the requirement of dynamical dark energy and the avoidance of a breakdown of perturbation theory. Studying the linear perturbations around the FLRW background the results are, however, quite insensitive to the details of the constraints leading to a modified effective gravitational constant or a non-vanishing sound speed for dust.

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Alexander Ganz. 2022-03-23. Dynamical Dark Energy in Minimally Modified Gravity. https://doi.org/10.1088/1475-7516%2F2022%2F08%2F074

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