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arXiv · 2205.05674

Vector stability in quadratic metric-affine theories

Alejandro Jiménez-Cano·Francisco José Maldonado Torralba
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Abstract

In this work we study the stability of the four vector irreducible pieces of the torsion and the nonmetricity tensors in the general quadratic metric-affine Lagrangian in 4 dimensions. The goal will be to elucidate under which conditions the spin-1 modes associated to such vectors can propagate in a safe way, together with the graviton. This highly constrains the theory reducing the parameter space of the quadratic curvature part from 16 to 5 parameters. We also study the sub-case of Weyl-Cartan gravity, proving that the stability of the vector sector is only compatible with an Einstein-Proca theory for the Weyl vector.

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Alejandro Jiménez-Cano, Francisco José Maldonado Torralba. 2022-05-11. Vector stability in quadratic metric-affine theories. https://doi.org/10.1088/1475-7516%2F2022%2F09%2F044

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