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arXiv · 2506.22548

Constraining Cubic Curvature Corrections to General Relativity with Quasi-Periodic Oscillations

Alireza Allahyari·Liang Ma·Shinji Mukohyama·Yi Pang
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Abstract

We investigate observational constraints on cubic curvature corrections to general relativity by analyzing quasi-periodic oscillations (QPOs) in accreting black hole systems. In particular, we study Kerr black hole solution corrected by cubic curvature terms parameterized by $\beta_5$ and $\beta_6$. While $\beta_6$ corresponds to a field-redefinition invariant structure, the $\beta_5$ term can in principle be removed via a field redefinition. Nonetheless, since we work in the frame where the accreting matter minimally couples to the metric, $\beta_5$ is in general present. Utilizing the corrected metric, we compute the QPO frequencies within the relativistic precession framework. Using observational data from GRO J1655$-$40 and a Bayesian analysis, we constrain the coupling parameters to $-12.31<\frac{\beta_5}{(5 M_\odot)^4}<24.15$ and $-1.99<\frac{\beta_6}{(5 M_\odot)^4}<0.30$ at 2-$\sigma$. These bounds improve upon existing constraints from big-bang nucleosynthesis and the speed of gravitational waves.

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Alireza Allahyari, Liang Ma, Shinji Mukohyama, Yi Pang. 2025-06-27. Constraining Cubic Curvature Corrections to General Relativity with Quasi-Periodic Oscillations. https://doi.org/10.1088/1475-7516%2F2025%2F11%2F011

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