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Essential renormalization group equation for gravity coupled to a scalar field

Nobuyoshi Ohta1,* and Masatoshi Yamada2,†

  • *Contact author: ohtan.gm@gmail.com
  • †Contact author: m.yamada@kwansei.ac.jp
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Phys. Rev. D 112, 066013 – Published 22 September, 2025

DOI: https://doi.org/10.1103/16c5-73q2

Abstract

We study the essential renormalization group equation, in which inessential couplings are removed via field redefinitions, for Einstein gravity coupled to a massive scalar field in the presence of a cosmological constant. Our results indicate that perturbatively nonrenormalizable terms can be eliminated due to the cosmological term, in contrast to the case of perturbation around flat spacetime. We find a nontrivial fixed point for the Newton coupling and the cosmological term.

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Phys. Rev. D 112, 066013– Published 22 September, 2025
  • Received 10 June 2025
  • Accepted 5 September 2025
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