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arXiv · 1709.04249

Observable traces of non-metricity: new constraints on metric-affine gravity

A. Delhom I Latorre·Gonzalo J. Olmo·Michele Ronco
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Abstract

Relaxing the Riemannian condition to incorporate geometric quantities such as torsion and non-metricity may allow to explore new physics associated with defects in a hypothetical space-time microstructure. Here we show that non-metricity produces observable effects in quantum fields in the form of 4-fermion contact interactions, thereby allowing us to constrain the scale of non-metricity to be greater than 1 TeV by using results on Bhabha scattering. Our analysis is carried out in the framework of a wide class of theories of gravity in the metric-affine approach. The bound obtained represents an improvement of several orders of magnitude to previous experimental constraints.

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A. Delhom I Latorre, Gonzalo J. Olmo, Michele Ronco. 2017-09-13. Observable traces of non-metricity: new constraints on metric-affine gravity. https://doi.org/10.1016/j.physletb.2018.03.002

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