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arxiv: 2605.20562 · v1 · pith:VCJJXYO3new · submitted 2026-05-19 · 🌀 gr-qc

Convergence of post-Newtonian for quasi-circular non-precessing comparable mass ratios BBHs

Pith reviewed 2026-05-21 06:17 UTC · model grok-4.3

classification 🌀 gr-qc
keywords post-Newtonian expansionnumerical relativitybinary black holesenergy fluxseries convergencegravitational wavesquasi-circular orbitsBMS frame
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The pith

Higher post-Newtonian orders keep reducing the gap to numerical relativity in binary black hole energy flux up to orbital velocity 0.45.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper checks whether adding more terms in the post-Newtonian series steadily improves how well it predicts the energy carried away by gravitational waves from two black holes orbiting each other. The authors align the analytic and numerical descriptions in the same coordinate frame at future null infinity and adjust a few free parameters in the PN model using only the early part of the simulation. They find that the match gets better with each added order until the orbital speed reaches roughly 0.45, after which extra terms stop helping and the series begins to diverge. Readers care because this sets a practical limit on how far analytic formulas can be trusted before full numerical simulations must take over in models used to detect and interpret gravitational-wave signals.

Core claim

For orbital velocities v ≲ 0.45, successively higher post-Newtonian orders reduce the discrepancy between the PN energy flux at future null infinity and the corresponding numerical relativity result, with the incomplete 6PN expression giving the smallest residual among the orders tested. The improvement is non-monotonic, exhibiting local extrema near 2.5PN and 4PN. As v approaches ∼0.5 near the innermost circular orbit, further PN orders cease to improve the agreement, signalling the breakdown of convergence.

What carries the argument

Gauge-consistent comparison of PN and NR energy flux after calibrating intrinsic PN parameters by a fit to the early-inspiral NR waveform, performed inside a common BMS frame at future null infinity.

If this is right

  • The first local minimum in the PN–NR residual cannot be used to select the optimal truncation order of the series.
  • High-order PN calculations beyond 5PN remain worthwhile because they demonstrably tighten the match up to v ≲ 0.45.
  • The accuracy demands placed on numerical relativity waveforms for validating future PN terms become clearer.
  • Near the innermost circular orbit at v ∼ 0.5 the PN series loses its ability to track the numerical flux, so hybrid models must switch earlier than the radius of convergence would suggest.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Waveform models for current detectors may need to blend PN and NR descriptions at lower velocities than the 0.45 threshold found here.
  • Repeating the test for spinning or eccentric binaries would map how the radius of convergence depends on spin and eccentricity.
  • The observed non-monotonic pattern hints that resummation methods could extend the useful range of PN expressions closer to merger.

Load-bearing premise

Fitting the free parameters of the PN model to the numerical waveform in the early inspiral produces a calibration that remains unbiased and does not artificially improve or hide the convergence behavior at later times and higher velocities.

What would settle it

A complete 6PN or 6.5PN energy-flux calculation that shows a larger mismatch with the same NR data at v = 0.40 than the 5PN result would falsify the claim of continued improvement.

Figures

Figures reproduced from arXiv: 2605.20562 by B\'eatrice Bonga, Dongze Sun, Guido Da Re, Leo C. Stein.

Figure 1
Figure 1. Figure 1: FIG. 1. Solid colored curves: differences in energy flux [PITH_FULL_IMAGE:figures/full_fig_p005_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2. The energy flux residual [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
read the original abstract

Post-Newtonian (PN) theory provides the analytic foundation for modeling the early inspiral of binary black holes. However, as an asymptotic series, successive PN orders do not necessarily improve agreement with the full nonlinear dynamics. While this has been explored in the extreme-mass-ratio limit, comparable-mass systems most relevant to current observations have not been benchmarked as systematically at high PN order. We study the convergence of the PN series for non-spinning and quasi-circular systems by comparing the PN energy flux at future null infinity to a long, high-accuracy numerical relativity (NR) simulation. To enable a gauge-consistent comparison, we place both descriptions in the same BMS frame and calibrate the intrinsic PN parameters by fitting to the NR waveform in the early inspiral. We find that for orbital velocities $v\lesssim0.45$, higher PN orders continue to reduce the PN--NR flux discrepancy, with (incomplete) 6PN providing the best agreement among the orders considered. The improvement with PN order is non-monotonic with local extrema around 2.5PN and 4PN. This implies that the optimal truncation order of the PN series cannot be identified from the first local minimum in the energy flux residuals, contrary to suggestions in earlier work. As $v$ approaches $\sim 0.5$ near the innermost circular orbit, higher PN orders no longer improve the agreement between NR and PN, indicating a loss of convergence. These results motivate continued high-order PN calculations and clarify the NR accuracy needed to validate them.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 2 minor

Summary. The paper studies the convergence of the post-Newtonian (PN) series for the energy flux of quasi-circular, non-spinning binary black holes with comparable masses. After placing PN and a long, high-accuracy NR simulation in the same BMS frame and calibrating intrinsic PN parameters by fitting to the NR waveform in the early inspiral, the authors report that for orbital velocities v ≲ 0.45 higher PN orders (up to incomplete 6PN) continue to reduce the PN–NR flux discrepancy, with non-monotonic improvement featuring local extrema near 2.5PN and 4PN. They conclude that the first local minimum in residuals does not mark optimal truncation and that convergence is lost near v ∼ 0.5.

Significance. If the central claim holds after addressing calibration concerns, the work supplies a valuable benchmark for the practical range of PN approximations in comparable-mass systems, directly relevant to gravitational-wave modeling. The use of a consistent BMS frame and a long high-accuracy NR run are clear strengths that enable a controlled comparison.

major comments (1)
  1. [methods section on fitting and BMS-frame comparison] The calibration of intrinsic PN parameters to early-inspiral NR data (described in the methods section on gauge-consistent comparison and fitting) is load-bearing for the convergence claims at v ≲ 0.45. Because the fit occurs where the series is already expected to be accurate, it may absorb unknown higher-order coefficients or residual gauge differences that would otherwise appear at larger velocities. The manuscript does not report the magnitude of the fitted corrections nor present a control comparison with unfitted coefficients, leaving open the possibility that the reported non-monotonic improvement and superiority of 6PN are partly artifacts of the calibration procedure.
minor comments (2)
  1. [results section on flux comparison] Details on error bars, exact fitting windows, and the quantitative definition of flux residuals (e.g., how the discrepancy is integrated or averaged) are not fully specified, which makes it difficult to assess the statistical significance of the local extrema around 2.5PN and 4PN.
  2. [abstract and § on PN orders] The abstract and main text should clarify whether the 6PN result is strictly incomplete and, if so, which terms are missing, to allow readers to judge the precise order being tested.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their careful reading of the manuscript and for highlighting the strengths of the BMS-frame alignment and the long high-accuracy NR simulation. We address the single major comment below and have revised the manuscript accordingly.

read point-by-point responses
  1. Referee: [methods section on fitting and BMS-frame comparison] The calibration of intrinsic PN parameters to early-inspiral NR data (described in the methods section on gauge-consistent comparison and fitting) is load-bearing for the convergence claims at v ≲ 0.45. Because the fit occurs where the series is already expected to be accurate, it may absorb unknown higher-order coefficients or residual gauge differences that would otherwise appear at larger velocities. The manuscript does not report the magnitude of the fitted corrections nor present a control comparison with unfitted coefficients, leaving open the possibility that the reported non-monotonic improvement and superiority of 6PN are partly artifacts of the calibration procedure.

    Authors: We agree that the calibration step is central to the comparison and thank the referee for the opportunity to strengthen the presentation. The fit adjusts only the initial orbital frequency and phase (intrinsic parameters) to enforce BMS-frame consistency in the early inspiral; it does not introduce or absorb any higher-order PN coefficients, which remain fixed at each truncation order. In the revised manuscript we now report the magnitude of these corrections explicitly (they are at the level of a few parts in 10^4). We have also added a short sensitivity study showing that modest variations in the fit window leave the non-monotonic residual pattern and the ordering of the PN truncations unchanged at v ≲ 0.45. A direct unfitted comparison would mix residual gauge mismatch into the flux difference, defeating the controlled test of PN convergence that the BMS alignment was designed to enable. We therefore view the calibration as necessary rather than artifact-inducing, but we have clarified this reasoning in the text. revision: yes

Circularity Check

1 steps flagged

Fitting intrinsic PN parameters to early-inspiral NR data biases the claimed convergence test at higher velocities

specific steps
  1. fitted input called prediction [Abstract]
    "To enable a gauge-consistent comparison, we place both descriptions in the same BMS frame and calibrate the intrinsic PN parameters by fitting to the NR waveform in the early inspiral. We find that for orbital velocities v≲0.45, higher PN orders continue to reduce the PN--NR flux discrepancy, with (incomplete) 6PN providing the best agreement among the orders considered."

    The intrinsic parameters are fitted directly to early-inspiral NR data. The claimed reduction in flux discrepancy with increasing PN order is then measured using those same fitted parameters at higher velocities. Because the fit can absorb unknown higher-order or gauge effects in an order-dependent way, the reported improvement with PN order is not an independent verification of the series but is statistically influenced by the calibration to the input NR data.

full rationale

The paper's central result—that higher PN orders (up to incomplete 6PN) reduce PN–NR flux discrepancy for v ≲ 0.45—is obtained only after calibrating intrinsic PN parameters by a fit to the NR waveform in the early inspiral. This fit is performed precisely where the PN series is already expected to be accurate, allowing order-dependent adjustments to absorb discrepancies that would otherwise appear at larger v. The subsequent comparison of residuals at higher velocities therefore depends on the fitted inputs rather than constituting an independent test of the unfitted PN series. No control comparison with unfitted coefficients is reported, so the observed non-monotonic improvement and superiority of 6PN reduce, at least in part, to the calibration procedure itself.

Axiom & Free-Parameter Ledger

1 free parameters · 1 axioms · 0 invented entities

The central comparison rests on the ability to place PN and NR in a common BMS frame and on the validity of fitting a small set of intrinsic PN parameters to early-inspiral NR data.

free parameters (1)
  • intrinsic PN parameters
    Calibrated by fitting to the NR waveform in the early inspiral to enable gauge-consistent comparison.
axioms (1)
  • domain assumption BMS frame alignment between PN and NR descriptions is accurate and sufficient for flux comparison
    Invoked to enable a gauge-consistent comparison of energy flux at future null infinity.

pith-pipeline@v0.9.0 · 5818 in / 1368 out tokens · 65272 ms · 2026-05-21T06:17:57.280996+00:00 · methodology

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Reference graph

Works this paper leans on

55 extracted references · 55 canonical work pages · 23 internal anchors

  1. [1]

    The Cauchy evolution is performed using the Spectral Einstein Code (SpEC) [24] and the CCE evo- lution is performed using the SpECTRE code [25]

    NR waveform and energy flux We use a NR waveform computed using Cauchy- characteristic evolution (CCE) [22, 23] as the reference waveform. The Cauchy evolution is performed using the Spectral Einstein Code (SpEC) [24] and the CCE evo- lution is performed using the SpECTRE code [25]. The resulting waveform is given directly at future null infinity I +, alo...

  2. [2]

    Theorbitaldynamicsand gravitational-wave phase are modeled using the TaylorT1 approximant

    PN waveform and energy flux For the PN waveforms, we also consider quasi-circular, non-spinning binaries characterized by the total massM andmassratio q = m1/m2 ≥ 1. Theorbitaldynamicsand gravitational-wave phase are modeled using the TaylorT1 approximant. In this approach, one writes the binary’s binding energy E, gravitational-wave energy flux to null i...

  3. [3]

    matching window

    Comparing NR and PN energy flux The energy flux atI + is invariant under rotations, but not under boosts, spatial translations, or proper BMS supertranslations. These transformations change the la- beling of the constant-retarded-time cross sections ofI +, and hence modify the flux as a function of retarded time. To make meaningful comparisons between PN ...

  4. [4]

    Matching post-Newtonian and numerical relativity waveforms: systematic errors and a new phenomenological model for non-precessing black hole binaries

    L. Santamaria et al.,Matching post-Newtonian and numerical relativity waveforms: systematic errors and a new phenomenological model for non-precessing black hole binaries,Phys. Rev. D82(2010) 064016 [1005.3306]

  5. [5]

    Suitability of post-Newtonian/numerical-relativity hybrid waveforms for gravitational wave detectors

    I. MacDonald, S. Nissanke, H.P. Pfeiffer and H.P. Pfeiffer, Suitability of post-Newtonian/numerical-relativity hybrid waveforms for gravitational wave detectors,Class. Quant. Grav.28(2011) 134002 [1102.5128]

  6. [6]

    Uncertainty in hybrid gravitational waveforms: Optimizing initial orbital frequencies for binary black-hole simulations

    M. Boyle,Uncertainty in hybrid gravitational waveforms: Optimizing initial orbital frequencies for binary black-hole simulations,Phys. Rev.D84(2011) 064013 [1103.5088]

  7. [7]

    Suitability of hybrid gravitational waveforms for unequal-mass binaries

    I. MacDonald, A.H. Mroue, H.P. Pfeiffer, M. Boyle, L.E. Kidder, M.A. Scheel et al.,Suitability of hybrid gravitational waveforms for unequal-mass binaries,Phys. Rev.D87(2013) 024009 [1210.3007]

  8. [8]

    Surrogate model of hybridized numerical relativity binary black hole waveforms

    V. Varma, S.E. Field, M.A. Scheel, J. Blackman, L.E. Kidder and H.P. Pfeiffer,Surrogate model of hybridized numerical relativity binary black hole waveforms,Phys. Rev.D99(2019) 064045 [ 1812.07865]

  9. [9]

    Sadiq, Y

    J. Sadiq, Y. Zlochower, R. O’Shaughnessy and J. Lange, Hybrid waveforms for generic precessing binaries for gravitational-wave data analysis,Phys. Rev. D102 (2020) 024012 [2001.07109]

  10. [10]

    Mitman et al.,Fixing the BMS frame of numerical relativity waveforms with BMS charges,Phys

    K. Mitman et al.,Fixing the BMS frame of numerical relativity waveforms with BMS charges,Phys. Rev. D 106(2022) 084029 [2208.04356]

  11. [11]

    Numerical relativity surrogate model with memory effects and post-Newtonian hybridization,

    J. Yoo et al.,Numerical relativity surrogate model with memory effects and post-Newtonian hybridization,Phys. Rev. D108(2023) 064027 [2306.03148]

  12. [12]

    D. Sun, M. Boyle, K. Mitman, M.A. Scheel, L.C. Stein, S.A. Teukolsky et al.,Optimizing post-Newtonian parameters and fixing the BMS frame for numerical-relativity waveform hybridizations,Phys. Rev. D110(2024) 104076 [2403.10278]

  13. [13]

    Sun and L.C

    D. Sun and L.C. Stein,Parameter matching between horizon quasi-local and point-particle definitions at 1PN for quasi-circular and non spinning BBH systems in harmonic gauge,2510.25618

  14. [14]

    Futamase and B.F

    T. Futamase and B.F. Schutz,Newtonian and post-Newtonian approximations are asymptotic to general relativity,Phys. Rev. D28(1983) 2363

  15. [15]

    Bender and S

    C. Bender and S. Orszag,Advanced Mathematical Methods for Scientists and Engineers: Asymptotic Methods and Perturbation Theory, Advanced Mathematical Methods for Scientists and Engineers, Springer (1999)

  16. [16]

    Accuracy of the Post-Newtonian Approximation: Optimal Asymptotic Expansion for Quasi-Circular, Extreme-Mass Ratio Inspirals

    N. Yunes and E. Berti,Accuracy of the post-Newtonian approximation: Optimal asymptotic expansion for quasicircular, extreme-mass ratio inspirals,Phys. Rev. D 77(2008) 124006 [0803.1853]

  17. [17]

    Head-on collision of compact objects in general relativity: Comparison of post-Newtonian and perturbation approaches

    L.E. Simone, E. Poisson and C.M. Will,Headon collision of compact objects in general relativity: Comparison of postNewtonian and perturbation approaches,Phys. Rev. D52(1995) 4481 [gr-qc/9506080]

  18. [18]

    Gravitational Waves from a Particle in Circular Orbits around a Schwarzschild Black Hole to the 22nd Post-Newtonian Order

    R. Fujita,Gravitational Waves from a Particle in Circular Orbits around a Schwarzschild Black Hole to the 22nd Post-Newtonian Order,Prog. Theor. Phys.128 (2012) 971 [1211.5535]

  19. [19]

    Gravitational Waves from a Particle in Circular Orbits around a Rotating Black Hole to the 11th Post-Newtonian Order

    R. Fujita,Gravitational Waves from a Particle in Circular Orbits around a Rotating Black Hole to the 11th Post-Newtonian Order,PTEP2015(2015) 033E01 [1412.5689]

  20. [20]

    Gravitational radiation from a particle in circular orbit around a black hole. VI. Accuracy of the post-Newtonian expansion

    E. Poisson,Gravitational radiation from a particle in circular orbit around a black hole. 6. Accuracy of the postNewtonian expansion,Phys. Rev. D52(1995) 5719 [gr-qc/9505030]

  21. [21]

    N. Sago, R. Fujita and H. Nakano,Accuracy of the Post-Newtonian Approximation for Extreme-Mass Ratio Inspirals from Black-hole Perturbation Approach,Phys. Rev. D93(2016) 104023 [1601.02174]

  22. [22]

    The general relativistic two body problem

    T. Damour,The general relativistic two body problem, 1312.3505. 8

  23. [23]

    High-accuracy comparison of numerical relativity simulations with post-Newtonian expansions

    M. Boyle, D.A. Brown, L.E. Kidder, A.H. Mroue, H.P. Pfeiffer, M.A. Scheel et al.,High-accuracy comparison of numerical relativity simulations with post-Newtonian expansions,Phys. Rev. D76(2007) 124038 [0710.0158]

  24. [24]

    Moreschi,Supercenter of Mass System at Future Null Infinity,Class

    O.M. Moreschi,Supercenter of Mass System at Future Null Infinity,Class. Quant. Grav.5(1988) 423

  25. [25]

    ImprovedCauchy-characteristicevolutionsystemforhigh- precision numerical relativity waveforms,

    J. Moxon, M.A. Scheel and S.A. Teukolsky,Improved Cauchy-characteristic evolution system for high-precision numerical relativity waveforms,Phys. Rev. D102(2020) 044052 [2007.01339]

  26. [26]

    SpECTRE Cauchy-characteristic evolution system for rapid, precise waveform extraction,

    J. Moxon, M.A. Scheel, S.A. Teukolsky, N. Deppe, N. Fischer, F. Hébert et al.,SpECTRE Cauchy-characteristic evolution system for rapid, precise waveform extraction,Phys. Rev. D107(2023) 064013 [2110.08635]

  27. [27]

    The Spectral Einstein Code

    “The Spectral Einstein Code.” http://www.black-holes.org/SpEC.html

  28. [28]

    SpECTRE v2023.05.16

    N. Deppe, W. Throwe, L.E. Kidder, N.L. Vu, F. Hébert, J. Moxon et al., “SpECTRE v2023.05.16.” https://spectre-code.org, 5, 2023. 10.5281/zenodo.7942177

  29. [29]

    The SXS collaboration catalog of gravitational waveforms

    SXS Collaboration, “The SXS collaboration catalog of gravitational waveforms.” http://www.black-holes.org/waveforms

  30. [30]

    Boyle et al

    M. Boyle et al.,The SXS Collaboration catalog of binary black hole simulations,Class. Quant. Grav.36(2019) 195006 [1904.04831]

  31. [31]

    The SXS collaboration’s third catalog of binary black hole simulations,

    M.A. Scheel et al.,The SXS collaboration’s third catalog of binary black hole simulations,Class. Quant. Grav.42 (2025) 195017 [2505.13378]

  32. [32]

    M. Ruiz, R. Takahashi, M. Alcubierre and D. Nunez, Multipole expansions for energy and momenta carried by gravitational waves,Gen. Rel. Grav.40(2008) 2467 [0707.4654]

  33. [33]

    Trestini,Schott term in the binding energy for compact binaries on circular orbits at fourth post-Newtonian order,Phys

    D. Trestini,Schott term in the binding energy for compact binaries on circular orbits at fourth post-Newtonian order,Phys. Rev. D112(2025) 024076 [2504.13245]

  34. [34]

    Angular velocity of gravitational radiation from precessing binaries and the corotating frame

    M. Boyle,Angular velocity of gravitational radiation from precessing binaries and the corotating frame,Phys. Rev. D87(2013) 104006 [1302.2919]

  35. [35]

    Ap- proximate helical symmetry in compact binaries,

    A. Khairnar, L.C. Stein and M. Boyle,Approximate helical symmetry in compact binaries,Phys. Rev. D111 (2025) 024072 [2410.16373]

  36. [36]

    Boyle, D

    M. Boyle, D. Iozzo, L. Stein, A. Khairnar, H. Rüter, M. Scheel et al., “scri.” https://github.com/moble/scri, Nov., 2023. 10.5281/zenodo.4041971

  37. [37]

    Nonlocal-in-time action for the fourth post-Newtonian conservative dynamics of two-body systems

    T. Damour, P. Jaranowski and G. Schäfer, Nonlocal-in-time action for the fourth post-Newtonian conservative dynamics of two-body systems,Phys. Rev. D 89(2014) 064058 [1401.4548]

  38. [38]

    Center-of-Mass Equations of Motion and Conserved Integrals of Compact Binary Systems at the Fourth Post-Newtonian Order

    L. Bernard, L. Blanchet, G. Faye and T. Marchand, Center-of-Mass Equations of Motion and Conserved Integrals of Compact Binary Systems at the Fourth Post-Newtonian Order,Phys. Rev. D97(2018) 044037 [1711.00283]

  39. [39]

    Post-Newtonian Theory for Gravitational Waves

    L. Blanchet,Post-Newtonian Theory for Gravitational Waves,Living Rev. Rel.17(2014) 2 [1310.1528]

  40. [40]

    Blanchet, G

    L. Blanchet, G. Faye, Q. Henry, F. Larrouturou and D. Trestini,Gravitational-Wave Phasing of Quasicircular Compact Binary Systems to the Fourth-and-a-Half Post-Newtonian Order,Phys. Rev. Lett.131(2023) 121402 [2304.11185]

  41. [41]

    Energy and angular momentum flow into a black hole in a binary

    K. Alvi,Energy and angular momentum flow into a black hole in a binary,Phys. Rev. D64(2001) 104020 [gr-qc/0107080]

  42. [42]

    The third post-Newtonian gravitational wave polarisations and associated spherical harmonic modes for inspiralling compact binaries in quasi-circular orbits

    L. Blanchet, G. Faye, B.R. Iyer and S. Sinha,The Third post-Newtonian gravitational wave polarisations and associated spherical harmonic modes for inspiralling compact binaries in quasi-circular orbits,Class. Quant. Grav.25(2008) 165003 [0802.1249]

  43. [43]

    G. Faye, S. Marsat, L. Blanchet and B.R. Iyer,The third and a half post-Newtonian gravitational wave quadrupole mode for quasi-circular inspiralling compact binaries, Class. Quant. Grav.29(2012) 175004 [1204.1043]

  44. [44]

    G. Faye, L. Blanchet and B.R. Iyer,Non-linear multipole interactions and gravitational-wave octupole modes for inspiralling compact binaries to third-and-a-half post-Newtonian order,Class. Quant. Grav.32(2015) 045016 [1409.3546]

  45. [45]

    Blanchet, G

    L. Blanchet, G. Faye, Q. Henry, F. Larrouturou and D. Trestini,Gravitational-wave flux and quadrupole modes from quasicircular nonspinning compact binaries to the fourth post-Newtonian order,Phys. Rev. D108 (2023) 064041 [2304.11186]

  46. [46]

    Post-Newtonian corrections to the gravitational-wave memory for quasicircular, inspiralling compact binaries

    M. Favata,Post-Newtonian corrections to the gravitational-wave memory for quasi-circular, inspiralling compact binaries,Phys. Rev. D80(2009) 024002 [0812.0069]

  47. [47]

    Cunningham, C

    K. Cunningham, C. Kavanagh, A. Pound, D. Trestini, N. Warburton and J. Neef,Gravitational memory: new results from post-Newtonian and self-force theory,Class. Quant. Grav.42(2025) 135009 [2410.23950]

  48. [48]

    NRPNHybridization

    D. Sun, “NRPNHybridization.” https://github.com/dongzesun/NRPNHybridization

  49. [49]

    Press, S.A

    W.H. Press, S.A. Teukolsky, W.T. Vetterling and B.P. Flannery,Numerical Recipes: The Art of Scientific Computing, Cambridge University Press, 3 ed. (2007)

  50. [50]

    Mitman, L.C

    K. Mitman, L.C. Stein, M. Boyle, N. Deppe, L.E. Kidder, H.P. Pfeiffer et al.,Length dependence of waveform mismatch: a caveat on waveform accuracy,Class. Quant. Grav.42(2025) 117001 [2502.14025]

  51. [51]

    Blanchet, D

    L. Blanchet, D. Langlois and E. Ligout,Innermost stable circular orbit of arbitrary-mass compact binaries at fourth post-Newtonian order,Phys. Rev. D112(2025) 064025 [2505.01278]

  52. [52]

    Cho, R.A

    G. Cho, R.A. Porto and Z. Yang,Gravitational radiation from inspiralling compact objects: Spin effects to the fourth post-Newtonian order,Phys. Rev. D106(2022) L101501 [2201.05138]

  53. [53]

    Khalil,Gravitational spin-orbit dynamics at the fifth-and-a-half post-Newtonian order,Phys

    M. Khalil,Gravitational spin-orbit dynamics at the fifth-and-a-half post-Newtonian order,Phys. Rev. D104 (2021) 124015 [2110.12813]

  54. [54]

    J.-W. Kim, M. Levi and Z. Yin,Quadratic-in-spin interactions at fifth post-Newtonian order probe new physics,Phys. Lett. B834(2022) 137410 [2112.01509]

  55. [55]

    Second maya catalog of binary black hole numerical relativity waveforms,

    D. Ferguson et al.,Second MAYA catalog of binary black hole numerical relativity waveforms,Phys. Rev. D112 (2025) 044043 [2309.00262]