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arXiv · 2411.12954

Stability in Cubic Metric-Affine Gravity

Sebastian Bahamonde·Jorge Gigante Valcarcel
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Abstract

We analyse the stability issue of the vector and axial modes of the torsion and nonmetricity tensors around general backgrounds in the framework of cubic Metric-Affine Gravity. We show that the presence of cubic order invariants defined from the curvature, torsion and nonmetricity tensors allow the cancellation of the well-known instabilities arising in the vector and axial sectors of quadratic Metric-Affine Gravity. For the resulting theory, we also obtain Reissner-Nordstr\"om-like black hole solutions with dynamical torsion and nonmetricity, which in general include massive tensor modes for these quantities, thus avoiding further no-go theorems that potentially prevent a consistent interaction of massless higher spin fields in the quantum regime.

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BibTeXRIS

Sebastian Bahamonde, Jorge Gigante Valcarcel. 2024-11-20. Stability in Cubic Metric-Affine Gravity. https://doi.org/10.1103/physrevd.111.084058

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