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Equivalence principles in Weyl transverse gravity

Ana Alonso-Serrano*

Luis J. Garay†

Marek Liška‡

  • *Contact author: ana.alonso.serrano@aei.mpg.de
  • †Contact author: luisj.garay@ucm.es
  • ‡Contact author: liskama4@stp.dias.ie
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Phys. Rev. D 113, 024029 – Published 13 January, 2026

DOI: https://doi.org/10.1103/3k8r-s3vt

Abstract

There exist two consistent theories of massless, self-interacting gravitons, which differ by their local symmetries: general relativity and Weyl transverse gravity. We show that these two theories are also the only two metric descriptions of gravity in four spacetime dimensions which obey the equivalence principle for test gravitational physics. We further analyze how the weaker formulations of the equivalence principle are realized in Weyl transverse gravity (and its generalizations). The analysis sheds light on the behavior of matter fields in this theory.

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Phys. Rev. D 113, 024029– Published 13 January, 2026
  • Received 13 October 2025
  • Accepted 24 December 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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