Multi-Messenger Tension Mapping: GW-SNe Joint Analysis in Modified Gravity

Zheng et al. (2024) show that combining GW "dark sirens" with Type Ia supernovae (SNe Ia) improves cosmological constraints but fails to achieve precision. Meanwhile, Mancarella et al. (2021) demonstrate that modified gravity (parameterized by Ξ₀ ≠ 1) biases mass/H₀ estimates from GW populations. We propose a joint hierarchical framework where SNe Ia and GW data are analyzed simultaneously under modified gravity. This would test whether tensions (e.g., H₀ discrepancies) arise from unmodeled GW propagation effects. Unlike Zhang (2023), who assumes GR, our work would quantify how Ξ₀ deviations masquerade as astrophysical anomalies (e.g., mass-gap mergers). If Ξ₀ ≠ 1, we predict correlated biases in GW-SNe distance ladders—a testable signature for next-generation surveys (e.g., LSST + Einstein Telescope).

References:

1. Cosmology and modified gravitational wave propagation from binary black hole population models. M. Mancarella, Edwin Genoud-Prachex, M. Maggiore (2021). Physical Review D.
2. Joint constraints on cosmological parameters using future multi-band gravitational wave standard siren observations. Xin Zhang (2023). Chinese Physics C, High Energy Physics & Nuclear Physics.
3. Joint Observations of Late Universe Probes: Cosmological Parameter Constraints from Gravitational Wave and Type Ia Supernova Data. Jie Zheng, Xiaohong Liu, Jing Qi (2024). Astrophysical Journal.