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Naturally light distortion

Kazunori Nakayama

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Phys. Rev. D 114, 103518 – Published 10 November, 2026

DOI: https://doi.org/10.1103/grmd-pgl9

Abstract

In the most general formulation of gravity, the metric and connection are independent degrees of freedom, and the connection may include torsion and nonmetricity (or distortion, collectively) degrees of freedom, resulting in a huge number of possible dynamical fields. However, most fields are either nondynamical or extremely heavy and the general relativity is recovered at low energy. We find a unique naturally light vector- or scalarlike distortion field, which can be dynamical and have phenomenological implications. In particular, a light scalar particle that mixes with the Higgs boson naturally appears.

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Outline

Information

Phys. Rev. D 114, 103518– Published 10 November, 2026
  • Received 23 April 2026
  • Accepted 17 September 2026
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