Finite-distance effects and scalar suppression in massive gravity
Abstract
Pulsar timing arrays (PTAs) probe the stochastic gravitational wave (GW) background through the angular cross-correlations of timing residuals. For a GW background in general relativity (GR), the expected overlap reduction function (ORF) is given by the Hellings--Downs (HD) correlation. We investigate how a nonzero graviton mass modifies this prediction through a massive dispersion relation and additional vector and scalar polarizations, producing a modified effective ORF. In the massive limit, the finite-distance pulsar terms survive angular averaging, multiplying the correlations of all three polarization sectors by a pulsar-dependent factor that can enhance, suppress, or reverse them. We adopt a tensor Earth--Earth normalization that preserves the continuous finite-distance effect. In the massless limit, we find that the vector ORF vanishes and the scalar ORF approaches a finite breathing mode. We propose the phenomenological prescription ΩS/ΩT=AS(mg/ω)nS, with scalar amplitude parameter AS and suppression index nS>0. These results provide a consistent framework for future PTA analyses of massive gravity.
Related
- Binary black hole mergers in massive Einstein-scalar-Gauss-Bonnet gravity
- Absence of Magnetic Suppression in Massive Star Variability
- Devoured by a Hairy Gargantua: Probing Massive Scalar Charges with Non-minimal Curvature Coupling with Extreme-Mass-Ratio Inspirals
- Addressing the DESI DR2 phantom-crossing anomaly and enhanced H 0 tension with reconstructed scalar-tensor gravity
- Massive scalar fields in eccentric regime: Detectability and constraints from LISA observations of extreme mass-ratio inspirals
BibTeX
@misc{choi2026finitedistance,
title = {{Finite-distance effects and scalar suppression in massive gravity}},
author = {Chris Choi and Tina Kahniashvili and Barnabás Póczos},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.31912},
eprint = {2610.31912},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.31912},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Finite-distance effects and scalar suppression in massive gravity
AU - Chris Choi
AU - Tina Kahniashvili
AU - Barnabás Póczos
PY - 2026
DA - 2026/10/22
PB - arXiv
DO - 10.48550/arxiv.2610.31912
UR - https://arxiv.org/abs/2610.31912
AB - Pulsar timing arrays (PTAs) probe the stochastic gravitational wave (GW) background through the angular cross-correlations of timing residuals. For a GW background in general relativity (GR), the expected overlap reduction function (ORF) is given by the Hellings--Downs (HD) correlation. We investigate how a nonzero graviton mass modifies this prediction through a massive dispersion relation and additional vector and scalar polarizations, producing a modified effective ORF. In the massive limit, the finite-distance pulsar terms survive angular averaging, multiplying the correlations of all three polarization sectors by a pulsar-dependent factor that can enhance, suppress, or reverse them. We adopt a tensor Earth--Earth normalization that preserves the continuous finite-distance effect. In the massless limit, we find that the vector ORF vanishes and the scalar ORF approaches a finite breathing mode. We propose the phenomenological prescription Ω_S/Ω_T=A_S(m_g/ω)^n_S, with scalar amplitude parameter A_S and suppression index n_S>0. These results provide a consistent framework for future PTA analyses of massive gravity.
ER -