The first informative astrophysical calibration of gravitational-wave detectors is reported using GW240925 and GW250207.
hub Canonical reference
GWTC-4.0: Tests of General Relativity. III. Tests of the Remnants
Canonical reference. 83% of citing Pith papers cite this work as background.
abstract
This is the third paper of the set recording the results of the suite of tests of general relativity (GR) performed on the signals from the fourth Gravitational-Wave Transient Catalog (GWTC-4.0), where we focus on the remnants of the binary mergers. We examine for the first time 42 events from the first part of the fourth observing run of the LIGO-Virgo-KAGRA detectors, alongside events from the previous observation runs, restricting our analysis to the confident signals, which were measured in at least two detectors and that have false alarm rates $\le 10^{-3} \mathrm{yr}^{-1}$. This paper focuses on seven tests of the coalescence remnants. Three of these are tests of the ringdown and its consistency with the expected quasinormal mode spectrum of a Kerr black hole. Specifically, two tests analyze just the ringdown in the time domain, and the third test analyzes the entire signal in the frequency domain. Four tests allow for the existence of possible echoes arriving after the end of the ringdown, which are not expected in GR. We find overall consistency of the remnants with GR. When combining events by multiplying likelihoods (hierarchically), one analysis finds that the GR prediction lies at the boundary of the $98.6^{+1.4}_{-9.4}\%$ ($99.3^{+0.7}_{-4.5}\%$) credible region, an increase from $93.8^{+6.1}_{-20.0}\%$ ($94.9^{+4.4}_{-18.2}\%$) for GWTC-3.0. Here the ranges of values comes from bootstrapping to account for the finite number of events analyzed and suggest that some of the apparently significant deviation could be attributed to variance due to the finite catalog. Since the significance also decreases to 92.2% (96.2%) when including the more recent very loud event GW250114, there is no strong evidence for a GR deviation. We find no evidence for post-merger echoes in the events that were analyzed. (Abridged)
hub tools
citation-role summary
citation-polarity summary
years
2026 21representative citing papers
Numerical relativity simulations of black hole scattering in Einstein-scalar-Gauss-Bonnet gravity agree closely with effective-one-body analytic predictions.
Gravitational electric-magnetic duality at the light ring organizes and preserves quasinormal mode isospectrality in GR and selects duality-invariant higher-derivative corrections in effective field theories.
Multiband observations of eccentric binary black holes can constrain dipole-radiation deviations from general relativity to |b| ≲ 10^{-7} for a GW231123-like event when combining one year of space-based data with ground-informed priors.
Numerical simulations of equal-mass boson-star mergers reveal larger waveform deviations from black-hole binaries in late inspiral and merger, plus odd multipole excitations for certain scalar-field phases, with some signals degenerate until IMR consistency tests are applied.
Landau coefficients for scalarization phase transitions are calculated from first principles via reduction of the theory's energy functional to an effective energy function.
Polynomial models for the (2,2) post-merger waveform amplitudes of eccentric non-spinning binary black holes are constructed from numerical-relativity data as functions of symmetric mass ratio and two merger-time dynamical parameters.
Viscous neutron stars have new families of axial oscillation modes without perfect-fluid counterparts, featuring mode avoidance and long-lived modes.
GreyRing model based on greybody factors reproduces numerical relativity ringdown signals with mismatches of order 10^{-6} and enables a new post-merger consistency test of general relativity applied to GW250114.
Leading-order deviations from general relativity in scalar quasinormal modes of rotating black holes are computed numerically up to dimensionless spins of 0.99 in quadratic-curvature scalar-tensor theories.
Numerical simulations of collapsing scalarized neutron stars show scalar radiation energy of order 10^{-3} solar masses, orders of magnitude above the tensor quadrupolar emission, potentially observable to test modified gravity.
Bayesian analysis finds individual QNM frequencies near avoided crossings hard to resolve even under optimistic conditions, though collective AC waveform signatures may remain detectable if those modes dominate and slower-mode contamination is minimal.
An EFT consistency map transports cosmology-conditioned posteriors from scalar-tensor FLRW backgrounds to black-hole quasinormal-mode kernels, showing tensor-speed effects fall below ringdown detectability while other operators remain potentially active near black holes.
Bilinear products for black hole quasinormal modes on hyperboloidal foliations are divergent due to CPT transformations but can be regularized to define orthogonal modes and excitation coefficients.
Leading-order cubic-curvature corrections to scalar quasinormal modes of black holes with spins up to 0.99M are computed numerically for modes up to l=5 with relative errors below 10^{-4}.
Using TaylorF2 post-Newtonian waveforms truncated at ISCO, the study finds that Einstein Telescope and Cosmic Explorer can reach SNR of 100-350 and measure primary spin to 10^{-4}-10^{-3} precision for 0.1-2 solar mass exotic compact objects.
Orthonormal QNM analysis of GW250114 raises the significance of the first overtone of the ℓ=m=2 mode from 82.5% to 99.9% and detects no significant deviation from Kerr predictions.
The prompt response is ~1.2 times stronger than quasinormal mode excitation during inspiral and enables 99% accurate reconstruction of the full inspiral-merger-ringdown waveform when combined with other components.
Bayesian analysis of GW170817 with PPE framework and EM polarization constraints shows mild preference for scalar mode in quadrupole harmonics and improves bounds on non-GR parameters by up to 60%.
Reanalysis of flagged LVK events with waveform uncertainty models produces consistent spin and precession inferences across raw/deglitched data and multiple waveform approximants.
Bayesian constraints from GWTC-4 binary black hole inspirals show Johannsen metric deformation parameters α13 and ε3 consistent with zero, supporting the Kerr hypothesis.
citing papers explorer
-
GW240925 and GW250207: Astrophysical Calibration of Gravitational-wave Detectors
The first informative astrophysical calibration of gravitational-wave detectors is reported using GW240925 and GW250207.
-
Black-Hole Scattering in Einstein-scalar-Gauss-Bonnet: Numerical Relativity Meets Analytics
Numerical relativity simulations of black hole scattering in Einstein-scalar-Gauss-Bonnet gravity agree closely with effective-one-body analytic predictions.
-
Gravitational electric-magnetic duality at the light ring and quasinormal mode isospectrality in effective field theories
Gravitational electric-magnetic duality at the light ring organizes and preserves quasinormal mode isospectrality in GR and selects duality-invariant higher-derivative corrections in effective field theories.
-
Constraining Dipole Radiation with Multiband Gravitational Waves from Eccentric Binary Black Holes
Multiband observations of eccentric binary black holes can constrain dipole-radiation deviations from general relativity to |b| ≲ 10^{-7} for a GW231123-like event when combining one year of space-based data with ground-informed priors.
-
Lessons from binary dynamics of inspiralling equal-mass boson-star mergers
Numerical simulations of equal-mass boson-star mergers reveal larger waveform deviations from black-hole binaries in late inspiral and merger, plus odd multipole excitations for certain scalar-field phases, with some signals degenerate until IMR consistency tests are applied.
-
Underlying mechanisms of phase transitions in scalar-tensor theories
Landau coefficients for scalarization phase transitions are calculated from first principles via reduction of the theory's energy functional to an effective energy function.
-
Highly eccentric non-spinning binary black hole mergers: quadrupolar post-merger waveforms
Polynomial models for the (2,2) post-merger waveform amplitudes of eccentric non-spinning binary black holes are constructed from numerical-relativity data as functions of symmetric mass ratio and two merger-time dynamical parameters.
-
Axial Oscillations of Viscous Neutron Stars
Viscous neutron stars have new families of axial oscillation modes without perfect-fluid counterparts, featuring mode avoidance and long-lived modes.
-
Novel ringdown tests of general relativity with black hole greybody factors
GreyRing model based on greybody factors reproduces numerical relativity ringdown signals with mismatches of order 10^{-6} and enables a new post-merger consistency test of general relativity applied to GW250114.
-
Quadratic gravity corrections to scalar QNMs of rapidly rotating black holes
Leading-order deviations from general relativity in scalar quasinormal modes of rotating black holes are computed numerically up to dimensionless spins of 0.99 in quadratic-curvature scalar-tensor theories.
-
Rapidly Rotating Neutron Star Collapse in Massive Scalar-Tensor Theories
Numerical simulations of collapsing scalarized neutron stars show scalar radiation energy of order 10^{-3} solar masses, orders of magnitude above the tensor quadrupolar emission, potentially observable to test modified gravity.
-
Detectability of avoided crossings in black hole ringdowns
Bayesian analysis finds individual QNM frequencies near avoided crossings hard to resolve even under optimistic conditions, though collective AC waveform signatures may remain detectable if those modes dominate and slower-mode contamination is minimal.
-
A cosmology-to-ringdown EFT consistency map for scalar-tensor gravity
An EFT consistency map transports cosmology-conditioned posteriors from scalar-tensor FLRW backgrounds to black-hole quasinormal-mode kernels, showing tensor-speed effects fall below ringdown detectability while other operators remain potentially active near black holes.
-
Bilinear products and the orthogonality of quasinormal modes on hyperboloidal foliations
Bilinear products for black hole quasinormal modes on hyperboloidal foliations are divergent due to CPT transformations but can be regularized to define orthogonal modes and excitation coefficients.
-
Ringing of rapidly rotating black holes in effective field theory
Leading-order cubic-curvature corrections to scalar quasinormal modes of black holes with spins up to 0.99M are computed numerically for modes up to l=5 with relative errors below 10^{-4}.
-
Probing (sub-)solar-mass black holes and superspinars with current and next-generation gravitational-wave observatories
Using TaylorF2 post-Newtonian waveforms truncated at ISCO, the study finds that Einstein Telescope and Cosmic Explorer can reach SNR of 100-350 and measure primary spin to 10^{-4}-10^{-3} precision for 0.1-2 solar mass exotic compact objects.
-
Ringdown Analysis of GW250114 with Orthonormal Modes
Orthonormal QNM analysis of GW250114 raises the significance of the first overtone of the ℓ=m=2 mode from 82.5% to 99.9% and detects no significant deviation from Kerr predictions.
-
Prompt Response from Plunging Sources in Schwarzschild Spacetime
The prompt response is ~1.2 times stronger than quasinormal mode excitation during inspiral and enables 99% accurate reconstruction of the full inspiral-merger-ringdown waveform when combined with other components.
-
Tests of scalar polarizations with multi-messenger events
Bayesian analysis of GW170817 with PPE framework and EM polarization constraints shows mild preference for scalar mode in quadrupole harmonics and improves bounds on non-GR parameters by up to 60%.
-
Mitigating Systematic Errors in Parameter Estimation of Binary Black Hole Mergers in O1-O3 LIGO-Virgo Data
Reanalysis of flagged LVK events with waveform uncertainty models produces consistent spin and precession inferences across raw/deglitched data and multiple waveform approximants.
-
Improved Constraints on Non-Kerr Deviations from Binary Black Hole Inspirals Using GWTC-4 Data
Bayesian constraints from GWTC-4 binary black hole inspirals show Johannsen metric deformation parameters α13 and ε3 consistent with zero, supporting the Kerr hypothesis.