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arXiv · 1810.12276

Scale transformations in metric-affine geometry

Damianos Iosifidis·Tomi Koivisto
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Abstract

This article presents an exhaustive classification of metric-affine theories according to their scale symmetries. First it is clarified that there are three relevant definitions of a scale transformation. These correspond to a projective transformation of the connection, a rescaling of the orthonormal frame, and a combination of the two. The most general second order quadratic metric-affine action, including the parity-violating terms, is constructed in each of the three cases. The results can be straightforwardly generalised by including higher derivatives, and implemented in the general metric-affine, teleparallel, and symmetric teleparallel geometries.

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Damianos Iosifidis, Tomi Koivisto. 2018-10-29. Scale transformations in metric-affine geometry. https://doi.org/10.3390/universe5030082

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