REVIEW 4 major objections 8 minor 1 cited by
Quasi-normal modes of slowly-rotating Johannsen black holes
T0 review · 4 major / 8 minor · reviewed 2026-08-11 · deepseek-v4-flash
Pith's one-line read This paper claims that, under the assumptions of the Einstein equations, slow rotation, and small deformation parameters, the quasi-normal modes of a Johannsen black hole are dominated by a single deformation parameter, $\alpha_{13}$…
desk verdict Solid incremental contribution: new deformed Regge-Wheeler/Zerilli equations and an α13 ringdown mapping worth having, held back mainly by an unverified master-equation reduction and an extrapolated data constraint. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
The machinery is a pair of one-dimensional master equations of Regge–Wheeler and Zerilli type, $\partial^2\Psi/\partial r_*^2+V\Psi=0$, with effective potentials computed to first order in the spin $a$ and in the deformation parameters $\alpha_{13}$, $\alpha_{52}$, and $\epsilon_3$; the potentials are obtained by linearizing the Einstein equations about the slow-rotating Johannsen metric in the Regge–Wheeler gauge. The modes are found by the direct integration method, which matches an ingoing solution at the horizon to an outgoing solution at infinity by a Wronskian determinant condition, retaining the full horizon frequency $\omega_H$ even though the equations themselves are truncated. A correction factor $C=\omega_{\rm Teu}/\omega_{\rm Kerr}$ removes the slow-rotation error from the Kerr baseline, and the fitting formula $\mathrm{Re}(\omega)=\mathrm{Re}(\omega_{\rm Teu})+P_0\alpha_{13}+P_1\alpha_{13}a$ with tabulated coefficients $P_0$, $P_1$, $Q_0$, $Q_1$ converts the corrected frequencies into a direct mapping from ringdown data to $\alpha_{13}$.
What would settle it
Recompute the axial and polar quasi-normal modes at $a_*=0.4$ with a method that does not use the slow-rotation expansion, such as a Teukolsky-like equation for beyond-Kerr spacetimes, and check whether the $\alpha_{13}$ shift follows $P_0+P_1a$ to within the paper's quoted 0.2%–0.3% error; alternatively, repeat the perturbation calculation while keeping the perturbation of the effective stress–energy tensor that the Johannsen background requires and look for frequency shifts comparable to the $\alpha_{13}$ contribution.
Extended reading notes
Core claim
The central claim is that the quasi-normal modes of a Johannsen black hole, computed from the Einstein equations in the slow-rotation, small-deformation limit, are dominated by the deformation parameter $\alpha_{13}$. The axial and polar perturbation problems separate in this limit, giving deformed Regge–Wheeler and Zerilli master equations whose effective potentials contain $\alpha_{13}$, $\alpha_{52}$, and $\epsilon_3$ but not $\alpha_{22}$ at leading order. Because the slow-rotation approximation degrades the Kerr part of the answer, the authors calibrate the Kerr baseline against the exact Teukolsky result and fold the mismatch in as a correction factor, so the final frequency is $\omega_{\rm corr}=\omega_{\rm Non\text{-}Kerr}+(C-1)\omega_{\rm Kerr}$. For the fundamental $l=2$ and $l=3$ modes the result takes the form of a fitting formula with the reported coefficients, and the paper argues that, in this regime, a ringdown observation translates directly into a measurement of $\alpha_{13}$.
Load-bearing premise
The load-bearing premise is that the Johannsen metric, which is not a vacuum solution of the Einstein equations, can still be treated as a vacuum background whose gravitational perturbations obey the source-free Einstein equations, so that perturbations of the effective stress–energy tensor are neglected.
Editorial extensions
If this is right
- A ringdown detection from any low-spin remnant ($a_*<0.4$) can be converted directly into a measurement of $\alpha_{13}$ through $\alpha_{13}=f^{\rm GR}_{lmn}\delta f_{lmn}/(P_0+P_1 a)$, giving a theory-agnostic test of the Kerr hypothesis from one gravitational-wave event.
- The {2,2,1} ringdown of GW170104 yields $\alpha_{13}=-0.5^{+2.1}_{-4.0}$ at 90% confidence, consistent with general relativity and with the inspiral-based constraint on the same event.
- At leading order in the slow-rotation and small-deformation expansion, $\alpha_{22}$ drops out of the perturbation equations and $\alpha_{52}$, $\epsilon_3$ have weaker effects, so the ringdown test is effectively one-parameter in this regime.
- The tabulated coefficients for the fundamental and first-overtone modes with $l=2$ and $l=3$ keep fit errors below 0.3%, so the same formulas can be dropped directly into future ringdown templates.
Reading between the lines
- If the additivity of the correction factor in $\omega_{\rm corr}=\omega_{\rm Non\text{-}Kerr}+(C-1)\omega_{\rm Kerr}$ is not exact near $a_*=0.4$, the inferred $\alpha_{13}$ from an event at the edge of the validity range would carry a systematic bias; recomputing the modes without factorizing the slow-rotation error would quantify that bias.
- The no-source assumption means the computed modes describe the effective Einstein vacuum of the metric rather than any concrete theory; in a theory that really produces the Johannsen background, perturbations of its matter sector would generically shift the modes by an amount comparable to the $\alpha_{13}$ effect, so the quoted constraint should be read as a null test of the parametric family.
- The paper leaves the polar sector covered only by an assumption of near-isospectrality; because deformations generically break the equality of axial and polar spectra, measuring a difference between them in a loud ringdown would be a distinctive signature that this formalism is built to predict but has not yet computed.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript computes the quasi-normal modes (QNMs) of gravitational perturbations of slowly rotating Johannsen black holes, a parametrized non-Kerr metric designed for agnostic tests of GR. The authors linearize the Einstein equations about the Johannsen background to first order in the spin a and in the leading deformation parameters alpha_13, alpha_22, alpha_52, and epsilon_3, assume that the effective stress-energy supporting the background has no perturbations, and derive deformed Regge-Wheeler and Zerilli master equations whose effective potentials are given in Eq. (12) and Appendix A. Using the direct integration method, they compute the fundamental l = 2, m = 2 Kerr QNMs as a function of spin, introduce a correction factor calibrated against Teukolsky frequencies (Eqs. 18-19), and find that alpha_13 produces the largest frequency shifts among the four parameters (alpha_22 does not enter at the retained order). They fit the alpha_13 dependence with the linear formula Eq. (20), tabulate coefficients for all m of l = 2 and l = 3, and apply the l = 2, m = 2 formula to the ringdown of GW170104 using pyRing, finding alpha_13 = -0.5 +2.1 -4.0 at 90% CL, consistent with general relativity. The central claims are the alpha_13-dominance result, the fitting formula, and the GW170104 constraint; the central assumptions are the frozen effective-source approximation and the additivity of the Kerr correction factor.
Significance. If the leading-order approximations and the frozen-effective-source assumption are accepted, the paper is a useful and transparent contribution to agnostic strong-field tests of GR: it delivers the first QNM fitting formula for slowly rotating Johannsen black holes, with explicit master equations (Eq. 12 and Appendix A), a calibrated Kerr-Teukolsky comparison (Fig. 1), and a complete demonstration pipeline from theory to a ringdown constraint on alpha_13 using public LVK data and pyRing. The paper practices good epistemic hygiene: the main assumptions are stated in the text (Section III; Concluding Remarks), the Kerr limit is validated separately, and the headline constraint (consistent with GR) is falsifiable. The significance is nevertheless qualified by the correctness risks detailed below: the physical interpretation of the modes relies on an unverified linearized-consistency condition, the correction-factor additivity is untested for non-Kerr shifts, the l = 3 coefficient table contains a factor-of-10 error, and the astronomical constraint extrapolates the fit beyond its calibration domain.
major comments (4)
- [Section III, Eq. (12), and Appendix A] The perturbation scheme rests on the statement in Section III that, within the authors' agnostic approach, 'we assume that there are no perturbations on the right hand side,' i.e., delta-T = 0 and delta-G[h] = 0 on a background with nonvanishing G0. For such a background, the linearized contracted Bianchi identity reads nabla0_mu delta-G^{mu nu} + delta-Gamma^mu_{mu rho} G0^{rho nu} + delta-Gamma^nu_{mu rho} G0^{mu rho} = 0, so a solution of the reduced master equations (12) and (A1) can be a linearized solution of the full Einstein-matter system only if it additionally satisfies delta-Gamma dot G0 = 0. No check of this constraint is reported, and no matter model that would keep the effective T0 fixed under the perturbed connection is specified. Because G0 begins at first order in the deformation parameters, the unverified constraint is at the same order as the QNM shifts reported here. At a = 0 the axial sector of a spherical non-vacuum background does decouple, but the polar sector in general couples to matter perturbations, and the slow-rotation axial/polar separation relies on the same assumption away from spherical symmetry. The computed frequencies are therefore, strictly, frequencies of a reduced scalar equation on a fixed background; their status as gravitational-wave QNMs of an Einstein-matter system, and the interpretation of the Section VI constraint on alpha_13, depends on the frozen-source assumption holding. I recommend either numerically verifying that the direct-integration solutions satisfy the full set of linearized Einstein equations and the Bianchi constraint, or reframing the results as a phenomenological fixed-background computation and stating that limitation prominently in the abstract and conclusions.
- [Section V.B, Eqs. (18)-(19)] The correction-factor construction omega_corr = omega_Non-Kerr + (C - 1) omega_Kerr is exact by construction in the Kerr limit, so the validation in Fig. 1 tests the Kerr baseline but not the additivity assumption that the slow-rotation error of the Kerr part is independent of the deformation shift. The shift delta-omega_alpha = omega_Non-Kerr - omega_Kerr is computed with the same scheme whose uncorrected Im(omega) deviates from Teukolsky by about 10% at a = 0.3 and 20% at a = 0.4 (Fig. 1), whereas the alpha_13-induced change in Im(omega) is only about 4% of the base value at alpha_13 = 0.3 (Table I). The neglected O(a^2 alpha_13) and O(alpha_13^2) terms in the shift are not removed by the correction factor, so the expectation in Section V.B that the corrected non-Kerr frequencies are more accurate is an unvalidated premise. A concrete check would be a comparison of the corrected l = 2, m = 2 frequencies against one of the Teukolsky-like methods cited in Refs. [60-62] at a few points in the (a, alpha_13) plane; without such a comparison, or a quantitative bound on the neglected terms, the fitting coefficients and the GW170104 constraint carry an unquantified systematic error.
- [Appendix D, Table VII] Table VII is internally inconsistent with the numerical data in Table VI by a factor of approximately 10 in the P0 column. For example, at a = 0 and m = 0, Table VI gives Re(omega) = 0.5994 at alpha_13 = 0 and 0.5970 at alpha_13 = 0.1, i.e., dRe/dalpha_13 is about -0.024, whereas Table VII lists P0 = -0.0024; the l = 2 tables are mutually consistent (Table IV's P0 approximately -0.0195 for m = -2 reproduces Table III), so the discrepancy is not a convention issue. If Eq. (20) is used with the published l = 3 coefficients, the predicted alpha_13 shift is an order of magnitude too small. The P1, Q0, and Q1 columns of Tables VII and VIII appear consistent with Table VI, so the error seems localized to P0, but as printed the l = 3 real-part fitting formula, which is part of the paper's advertised product for l = 3 fundamental modes, is wrong and must be corrected.
- [Section VI and Table I] The GW170104 analysis extrapolates the fitting formula beyond its calibrated domain in two ways. First, the posterior final spin a = 0.31 +0.45 -0.28 reaches values up to about 0.76, while the fit is calibrated for a in [0, 0.3] and the abstract claims validity only for a* < 0.4; the paper acknowledges this only with the phrase 'exceeds slightly the range allowed with our methods.' Second, the reported 90% interval alpha_13 in [-4.46, 1.66] extends far outside the extended fit range alpha_13 in [-1, 1], where the O(alpha_13^2) and O(a^2 alpha_13) terms dropped in Eq. (20) are no longer small. The leakage is visible within the paper's own numbers: P1 changes from 0.0025 to 0.0166 when the alpha_13 range is widened from [-0.3, 0.3] to [-1, 1], showing that the coefficients are sensitive to the fitting window. Because the quoted uncertainty on alpha_13 does not include the truncation systematic, the constraint should be reported as an exploratory estimate with an explicit error budget for the extrapolation, or the posterior should be restricted to the calibrated region.
minor comments (8)
- [Throughout] Typos and wording: 'Zerlini' should be 'Zerilli' in Section I; the Section III heading reads 'MASTER EQUA TIONS'; Section IV.B uses 'DNSolve' instead of 'NDSolve'; Section V.C has 'The errors is not more than 0.2%'; Appendix C has 'relatee' instead of 'relates'.
- [Table III] In the a = 0 row at alpha_13 = 0.2, the m = -2 entry is 0.3798 while the other four m entries are 0.3698 or 0.3699; the 0.3798 value breaks the monotonic trend and appears to be a typo.
- [Abstract and Section V.C] The abstract states that the fitting formula is valid for a* < 0.4, but Section V.C calibrates the fit for a in [0, 0.3], and Fig. 1 shows the uncorrected imaginary part has about 20% error already at a = 0.4; the claimed validity range should be reconciled with the calibration range.
- [Abstract and Section V.B] The abstract's claim that alpha_13 has a stronger impact on the QNMs than alpha_52 and epsilon_3 is supported only by visual comparison of Figs. 2-4; please provide quantitative values (for example, dRe/dalpha and dIm/dalpha at a = 0 for each parameter) so that the headline claim is numerically documented.
- [Section V.C and Appendix D] The overtone numbering should be clarified: the paper labels the fundamental mode {l, m, 1}, while the LVK 'Kerr 220' convention of Ref. [4] is (l, m, n) = (2, 2, 0), and Section V.C states that Appendix D reports coefficients for the first overtone mode although the tables contain the fundamental-mode data; please align the two conventions.
- [References] Ref. [45] lists arXiv:1501.02809 for T. Johannsen, Phys. Rev. D 88, 044002 (2013); that arXiv identifier dates from January 2015 and appears to be incorrect, so please verify it. Several references (e.g., [3] and [33]) are missing titles or author initials in the bibliography.
- [Section VI, Eq. (22)] The mapping from delta-f and delta-tau to alpha_13 in Eq. (22) neglects O(a^2) and O(alpha_13^2) corrections, but the posterior on a is broad and enters through (P0 + P1 a) and (Q0 + Q1 a); a sentence stating that these denominator corrections are neglected relative to P0 and Q0 would make the approximation explicit.
- [Section VI] The extended fitting coefficients for alpha_13 in [-1, 1] (P0 = -0.0205, P1 = 0.0166, Q0 = 0.0136, Q1 = 0.0021) are quoted without fit residuals; please report the maximum error of the extended fit, since the stated 0.2% (l = 2) figure refers to the restricted calibration range.
Circularity Check
No load-bearing circularity: the QNM derivation is self-contained and benchmarked against Teukolsky Kerr results; only a by-construction ranking statement and a non-load-bearing self-citation keep the score slightly above zero.
-
other
[Abstract and Section V.B (Non-Kerr spacetime), with the truncation stated in Section III after Eq. (12)]
"We find that the deformation parameter α13 has a stronger impact on the quasi-normal modes than the other leading order deformation parameters (α22, α52, and ϵ3). ... We note that the deformation parameter α22 does not appear in the effective potential within our approximations."
The ranking of α13 over α22 is fixed by the paper's first-order truncation scheme rather than by the QNM calculation itself. In the slowly-rotating metric (Eq. 3), α22 enters only through the gtϕ combination aΣ sin^2θ(A1A2 r^2−Δ), which is O(a α22) and is dropped when terms of second order in spin and deformation parameters are neglected. The paper itself states that α22 does not appear in the effective potential. Thus the abstract's comparative claim reduces, by construction, to the truncation choice. This statement is not load-bearing: the fitting formula and the GW170104 constraint depend only on the computed α13 dependence, so this is a minor overstatement rather than a circular derivation of the main results.
full rationale
The central derivation computes QNM frequencies by linearizing the Einstein equations around the Johannsen background, assuming no perturbations of the effective stress-energy tensor, separating axial and polar perturbations, and solving the resulting Regge-Wheeler/Zerilli-type equations by direct integration. The slow-rotation Kerr limit is validated against Teukolsky results, and the correction factor C is anchored to that external benchmark, so the calibration is not circular. The fitting coefficients P0, P1, Q0, Q1 are fit to the paper's own numerical QNM values and then used to convert independent pyRing posteriors for δf and δτ into a constraint on α13; this is a standard fitting-plus-inference pipeline, not a fitted parameter renamed as a prediction. The agreement with the earlier inspiral constraint (Ref. [6]) is a consistency comparison and is not load-bearing. The only mild issue is the abstract's ranking of α13 against α22, which is a by-construction artifact of the first-order truncation; it does not affect the QNM frequencies or the GW constraint. The frozen effective-source assumption (δT=0) is a physical modeling choice that may be questioned, but it is an input assumption rather than a circular step.
Assumptions & free parameters
free parameters (3)
- P0, P1, Q0, Q1 for l=2, m=2 fitting formula =
-0.0197, 0.0025, 0.0130, -0.0095 (Table I)
- Extended P0, P1, Q0, Q1 for alpha_13 in [-1, 1] =
-0.0205, 0.0166, 0.0136, 0.0021 (Section VI)
- alpha_13 =
-0.5 +2.1 -4.0 (90% CL, combined constraint)
assumptions (6)
- domain assumption Johannsen metric with leading deformation parameters alpha_13, alpha_22, alpha_52, epsilon_3 describes the background spacetime.
- ad hoc to paper Gravitational perturbations satisfy the vacuum Einstein equations with no perturbation of the effective stress-energy tensor.
- domain assumption Only terms linear in spin a and in the deformation parameters are kept.
- domain assumption Axial and polar perturbations have approximately the same QNM spectrum.
- ad hoc to paper The correction factor C = omega_Teu / omega_Kerr computed for Kerr can be applied additively to the non-Kerr frequency shift.
- standard math Standard results of BH perturbation theory, including the Regge-Wheeler gauge, tortoise coordinates, and the Wronskian condition for QNMs.
invented entities (1)
-
Effective stress-energy tensor supporting the Johannsen metric
Cite this review
Pith. "Pith review of Quasi-normal modes of slowly-rotating Johannsen black holes." pith.science (2026). https://pith.science/paper/BFTG3VR7
@misc{pith2026241208205,
author = {Pith},
title = {Pith review of: Quasi-normal modes of slowly-rotating Johannsen black holes},
year = {2026},
howpublished = {\url{https://pith.science/paper/BFTG3VR7}},
note = {Machine review of arXiv:2412.08205}
}
abstract
The detection of gravitational waves with ground-based laser interferometers has opened a new window to test and constrain General Relativity (GR) in the strong, dynamical, and non-linear regime. In this paper, we follow an agnostic approach and we study the quasi-normal modes of gravitational perturbations of Johannsen black holes under the assumptions of the validity of the Einstein Equations and of low values of the black hole spin parameter and deformation parameters. We find that the deformation parameter $\alpha_{13}$ has a stronger impact on the quasi-normal modes than the other leading order deformation parameters ($\alpha_{22}$, $\alpha_{52}$, and $\epsilon_{3}$). We derive a fitting formula for the fundamental modes with $l=2$ and $l=3$ for the deformation parameter $\alpha_{13}$ valid in the slow rotation approximation ($a_* < 0.4$). Finally, we constrain $\alpha_{13}$ from the event GW170104; within our analysis, we find that the data of GW170104 are consistent with the predictions of GR.
Figures
Figures from the paper (4 more)
Forward citations
Cited by 1 Pith paper
-
Computing spectral shifts for Johannsen-Psaltis black holes
Slowly rotating Johannsen–Psaltis black holes have definite-parity quasinormal modes with even/odd frequency shifts split by the deviation parameter, computed here through ℓ=10.
Reference graph
Works this paper leans on
-
[1]
C. M. Will, Living Rev. Rel. 17, 4 (2014), arXiv:1403.7377 [gr-qc]
arXiv 2014
-
[2]
B. P. Abbott et al. (LIGO Scientific, Virgo), Phys. Rev. Lett. 116, 221101 (2016), [Erratum: Phys.Rev.Lett. 121, 129902 (2018)], arXiv:1602.03841 [gr-qc]
arXiv 2016
-
[3]
N. Yunes, K. Yagi, and F. Pretorius, Physical Review D 94 (2016), 10.1103/physrevd.94.084002
-
[4]
R. Abbott et al. (LIGO Scientific, Virgo), Phys. Rev. D 103, 122002 (2021), arXiv:2010.14529 [gr-qc]
arXiv 2021
-
[5]
A. Cardenas-Avendano, S. Nampalliwar, and N. Yunes, Class. Quant. Grav. 37, 135008 (2020), arXiv:1912.08062 [gr-qc]
arXiv 2020
-
[6]
S. Shashank and C. Bambi, Phys. Rev. D 105, 104004 (2022), arXiv:2112.05388 [gr-qc]
arXiv 2022
-
[7]
Z. Cao, S. Nampalliwar, C. Bambi, T. Dauser, and J. A. Garcia, Phys. Rev. Lett. 120, 051101 (2018), 13 FIG. 6. Posteriors for pyRing analysis of GW170104. arXiv:1709.00219 [gr-qc]
arXiv 2018
-
[8]
A. Tripathi, S. Nampalliwar, A. B. Abdikamalov, D. Ayzenberg, C. Bambi, T. Dauser, J. A. Gar- cia, and A. Marinucci, Astrophys. J. 875, 56 (2019), arXiv:1811.08148 [gr-qc]
arXiv 2019
Show all 61 references
-
[9]
Tripathi, A
A. Tripathi, A. B. Abdikamalov, D. Ayzenberg, C. Bambi, V. Grinberg, and M. Zhou, Astrophys. J. 907, 31 (2021), arXiv:2010.13474 [astro-ph.HE]
2021 arXiv
-
[10]
Tripathi, Y
A. Tripathi, Y. Zhang, A. B. Abdikamalov, D. Ayzen- berg, C. Bambi, J. Jiang, H. Liu, and M. Zhou, Astro- phys. J. 913, 79 (2021), arXiv:2012.10669 [astro-ph.HE]
2021 arXiv
-
[11]
Bambi, K
C. Bambi, K. Freese, S. Vagnozzi, and L. Visinelli, Phys. Rev. D 100, 044057 (2019), arXiv:1904.12983 [gr-qc]
2019 arXiv
-
[12]
Psaltis et al
D. Psaltis et al. (Event Horizon Telescope), Phys. Rev. Lett. 125, 141104 (2020), arXiv:2010.01055 [gr-qc]
2020 arXiv
-
[13]
Akiyama et al.(Event Horizon Telescope), Astrophys
K. Akiyama et al.(Event Horizon Telescope), Astrophys. J. Lett. 930, L17 (2022), arXiv:2311.09484 [astro-ph.HE]
2022 arXiv
-
[14]
Vagnozzi et al., Class
S. Vagnozzi et al., Class. Quant. Grav.40, 165007 (2023), arXiv:2205.07787 [gr-qc]
2023 arXiv
-
[15]
P. T. Chrusciel, J. Lopes Costa, and M. Heusler, Living Rev. Rel. 15, 7 (2012), arXiv:1205.6112 [gr-qc]
2012 arXiv
-
[16]
Bambi, Black Holes: A Laboratory for Testing Strong Gravity (Springer, 2017)
C. Bambi, Black Holes: A Laboratory for Testing Strong Gravity (Springer, 2017)
2017
- [17]
-
[18]
Yagi and L
K. Yagi and L. C. Stein, Class. Quant. Grav. 33, 054001 (2016), arXiv:1602.02413 [gr-qc]
2016 arXiv
- [19]
-
[20]
Bambi, (2022), arXiv:2210.05322 [gr-qc]
C. Bambi, (2022), arXiv:2210.05322 [gr-qc]. 14 FIG. 7. Comparison among radial ring-down waveforms Kerr and Johannsen spacetimes
2022 arXiv
-
[21]
Berti, K
E. Berti, K. Yagi, and N. Yunes, General Relativity and Gravitation 50 (2018), 10.1007/s10714-018-2362-8
2018 doi
-
[22]
Shashank, in 57th Rencontres de Moriond on Gravita- tion (2023) arXiv:2312.02234 [gr-qc]
S. Shashank, in 57th Rencontres de Moriond on Gravita- tion (2023) arXiv:2312.02234 [gr-qc]
2023 arXiv
-
[23]
Shashank, C
S. Shashank, C. Bambi, and R. Roy, in 7th Interna- tional Workshop on the TianQin Science Mission(2024) arXiv:2407.13798 [gr-qc]
2024
-
[24]
C. A. Benavides-Gallego, S. Shashank, and H. Xu, (2024), arXiv:2411.13897 [gr-qc]
2024 arXiv
-
[25]
D. Das, S. Shashank, and C. Bambi, Eur. Phys. J. C 84, 1237 (2024), arXiv:2406.03846 [gr-qc]
2024 arXiv
-
[26]
S. Riaz, S. Shashank, R. Roy, A. B. Abdikamalov, D. Ayzenberg, C. Bambi, Z. Zhang, and M. Zhou, JCAP 10, 040 (2022), arXiv:2206.03729 [gr-qc]
2022 arXiv
-
[27]
Berti, V
E. Berti, V. Cardoso, and A. O. Starinets, Classical and Quantum Gravity 26, 163001 (2009)
2009
-
[28]
Pani, International Journal of Modern Physics A 28, 1340018 (2013)
P. Pani, International Journal of Modern Physics A 28, 1340018 (2013)
2013
-
[29]
K. D. Kokkotas and B. G. Schmidt, Living Reviews in Relativity 2 (1999), 10.12942/lrr-1999-2
1999 doi
-
[31]
R. A. Konoplya and A. Zhidenko, Reviews of Modern Physics 83, 793–836 (2011)
2011
-
[32]
Berti, E
E. Berti, E. Barausse, and V. Cardoso, Classical and Quantum Gravity 32, 243001 (2015)
2015
-
[33]
Barack, V
L. Barack, V. Cardoso, and Nissanke, Classical and Quantum Gravity 36, 143001 (2019)
2019
-
[34]
Tests of gen- eral relativity and fundamental physics with space-based gravitational wave detectors,
E. Berti, E. Barausse, and I. Cholis, “Tests of gen- eral relativity and fundamental physics with space-based gravitational wave detectors,” (2019), arXiv:1903.02781 [astro-ph.HE]
2019 arXiv
-
[36]
Maselli, P
A. Maselli, P. Pani, L. Gualtieri, and E. Berti, Physical Review D 101 (2020), 10.1103/physrevd.101.024043
2020 doi
-
[37]
Pierini and L
L. Pierini and L. Gualtieri, Physical Review D 103 (2021), 10.1103/physrevd.103.124017
2021 doi
-
[38]
J. L. Bl´ azquez-Salcedo, C. F. Macedo, V. Cardoso, V. Ferrari, L. Gualtieri, F. S. Khoo, J. Kunz, and P. Pani, Physical Review D 94 (2016), 10.1103/phys- revd.94.104024
2016 doi
-
[39]
Wagle, N
P. Wagle, N. Yunes, and H. O. Silva, Physical Review D 105 (2022), 10.1103/physrevd.105.124003
2022 doi
-
[40]
H. O. Silva, A. Ghosh, and A. Buonanno, Phys. Rev. D 107, 044030 (2023), arXiv:2205.05132 [gr-qc]
2023 arXiv
-
[41]
S. H. V¨ olkel and E. Barausse, Phys. Rev. D102, 084025 (2020), arXiv:2007.02986 [gr-qc]
2020 arXiv
-
[42]
S. H. V¨ olkel and K. D. Kokkotas, Phys. Rev. D 100, 044026 (2019), arXiv:1908.00252 [gr-qc]
2019 arXiv
-
[43]
Carson and K
Z. Carson and K. Yagi, Phys. Rev. D 101, 084050 (2020), arXiv:2003.02374 [gr-qc]
2020 arXiv
-
[44]
Carson and K
Z. Carson and K. Yagi, Phys. Rev. D 101, 104030 (2020), arXiv:2003.00286 [gr-qc]
2020 arXiv
- [45]
-
[46]
Regge and J
T. Regge and J. A. Wheeler, Phys. Rev.108, 1063 (1957)
1957
-
[47]
Berti, V
E. Berti, V. Cardoso, and C. M. Will, Phys. Rev. D 73, 064030 (2006), arXiv:gr-qc/0512160
2006 arXiv
-
[48]
Berti, J
E. Berti, J. Cardoso, V. Cardoso, and M. Cavaglia, Phys. Rev. D 76, 104044 (2007), arXiv:0707.1202 [gr-qc]
2007 arXiv
-
[49]
Berti, V
E. Berti, V. Cardoso, and A. O. Starinets, Class. Quant. Grav. 26, 163001 (2009), arXiv:0905.2975 [gr-qc]
2009 arXiv
-
[50]
C. R. Harris et al. , Nature 585, 357 (2020), arXiv:2006.10256 [cs.MS]
2020 arXiv
-
[51]
pyRing: a time-domain ringdown analysis python package,
G. Carullo, W. Del Pozzo, and J. Veitch, “ pyRing: a time-domain ringdown analysis python package,” git.ligo.org/lscsoft/pyring (2023)
2023
-
[52]
Carullo, W
G. Carullo, W. Del Pozzo, and J. Veitch, Physical Re- view D 99 (2019), 10.1103/physrevd.99.123029
2019 doi
-
[53]
M. Isi, M. Giesler, W. M. Farr, M. A. Scheel, and S. A. Teukolsky, Physical Review Letters 123 (2019), 10.1103/physrevlett.123.111102
2019 doi
-
[54]
P. A. Seoane et al.(LISA), Living Rev. Rel. 26, 2 (2023), arXiv:2203.06016 [gr-qc]
2023 arXiv
-
[55]
Li et al., (2024), arXiv:2409.19665 [astro-ph.GA]
E.-K. Li et al., (2024), arXiv:2409.19665 [astro-ph.GA]
2024 arXiv
-
[56]
Hu and Y.-L
W.-R. Hu and Y.-L. Wu, Natl. Sci. Rev. 4, 685 (2017)
2017
-
[57]
Punturo et al., Class
M. Punturo et al., Class. Quant. Grav.27, 194002 (2010). 15
2010
-
[58]
Evans et al., (2021), arXiv:2109.09882 [astro-ph.IM]
M. Evans et al., (2021), arXiv:2109.09882 [astro-ph.IM]
2021 arXiv
-
[59]
A. K.-W. Chung, P. Wagle, and N. Yunes, Physical Re- view D 109 (2024), 10.1103/physrevd.109.044072
2024 doi
-
[60]
Hussain and A
A. Hussain and A. Zimmerman, Phys. Rev. D 106, 104018 (2022), arXiv:2206.10653 [gr-qc]
2022 arXiv
-
[61]
D. Li, P. Wagle, Y. Chen, and N. Yunes, Phys. Rev. X 13, 021029 (2023), arXiv:2206.10652 [gr-qc]
2023 arXiv
-
[62]
P. A. Cano, K. Fransen, T. Hertog, and S. Maenaut, Phys. Rev. D 108, 024040 (2023), arXiv:2304.02663 [gr- qc]
2023 arXiv
-
[63]
London, D
L. London, D. Shoemaker, and J. Healy, Phys. Rev. D 90, 124032 (2014). 16 TABLE III. QNM frequencies for l = 2, m = −2, −1, 0, 1, 2 a/M α13 m = −2 m = −1 m = 0 m = 1 m = 2 0 -0.3 0.3795, 0.0929 0.3795, 0.0929 0.3795, 0.0929 0.3795, 0.0929 0.3796, 0.0929 -0.2 0.3775, 0.0915 0.3...
2014
Reviewed August 11, 2026 · model on record in the stance chip above.
Discussion (0). Continue with ORCID to comment.