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arXiv · 2501.00376

Weak Gravity Limit in Newer General Relativity

Abstract

We analyse linearised field equations around the Minkowski metric with its standard flat parallel transport in models of Newer GR, that is quadratic actions in terms of nonmetricity tensor. We show that half of the freedom in choosing the model parameters is immediately fixed by asking for reasonable properties of tensors and vectors, defined with respect to spatial rotations, and accurately describe the much more complicated sector of scalars. In particular, we show that, from the teleparallel viewpoint, the model of STEGR with addition of a gradient squared of the metric determinant exhibits three halves new dynamical modes, and not just one like it was previously claimed.

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Alexey Golovnev, Sofia Klimova, A. N. Semenova, V. P. Vandeev. 2024-12-31. Weak Gravity Limit in Newer General Relativity. https://doi.org/10.3390/universe11050149

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