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arxiv: 2601.14979 · v2 · submitted 2026-01-21 · 🌀 gr-qc · astro-ph.GA· astro-ph.HE

Recognition: 2 theorem links

· Lean Theorem

The relativistic restricted three-body problem: geometry and motion around tidally perturbed black holes

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Pith reviewed 2026-05-16 12:14 UTC · model grok-4.3

classification 🌀 gr-qc astro-ph.GAastro-ph.HE
keywords tidally deformed black holesrelativistic geodesicschaos in orbitsrestricted three-body problemgravitational wavesepicyclic oscillationsextreme mass ratio inspiralsquasi-periodic oscillations
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The pith

Increasing tidal strength around a rotating black hole drives bound geodesics through four stages ending in no stable orbits.

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

The paper examines how the geometry of a tidally deformed rotating black hole affects the motion of nearby test particles. It finds that as the tidal field strengthens, initially regular bound geodesics first develop weak chaos, then some plunge into the black hole, a fraction become unbound, and finally no bound trajectories remain. Semi-analytic estimates pinpoint the critical tidal amplitudes for each transition. This framework offers insight into matter dynamics in black hole binaries relevant to gravitational wave astronomy and accretion processes.

Core claim

In the relativistic restricted three-body problem around a tidally deformed black hole, bound geodesics transition with rising tidal amplitude through weak chaos within bound motion, plunging trajectories, unbinding of remaining paths, and complete loss of bound orbits, accompanied by estimates for the critical tidal strengths at each stage.

What carries the argument

The tidally perturbed Kerr metric and the associated timelike geodesics, analyzed within an adiabatically evolving binary setup to model local structural changes in the restricted three-body problem.

Load-bearing premise

The description assumes test particles that do not back-react on the spacetime metric and that the binary evolves adiabatically with slow changes in parameters relative to orbital times.

What would settle it

Detection of bound orbits persisting at tidal amplitudes above the estimated critical value for complete depletion, perhaps through timing of orbits in a binary black hole system or signals from accreting matter.

Figures

Figures reproduced from arXiv: 2601.14979 by Takuya Katagiri, Vitor Cardoso.

Figure 1
Figure 1. Figure 1: FIG. 1: Magnitude of [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2 [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3: Prograde bound orbits with initial parameters ( [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4: Frequency ratio, [PITH_FULL_IMAGE:figures/full_fig_p006_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: FIG. 5: Evolution of originally bound orbits with initial parameters ( [PITH_FULL_IMAGE:figures/full_fig_p007_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: We have verified agreement of the above esti￾mate to a number of full numerical results obtained from Eq. (11) within the correct order of magnitude. Finally, we argue that an initially ISCO transitions to plunging orbits in the presence of tidal fields. To see this, we substitute Lˆ = √ 3r+ – the specific angular momen￾tum at the ISCO for the Schwarzschild BH – into dV /dr, yielding dV dr = (r − 3r+) 2 r+… view at source ↗
read the original abstract

We investigate the geometry of a tidally deformed, rotating black hole and timelike geodesics in its vicinity. Our framework provides a local picture of the structural evolution of a relativistic restricted three-body problem around a deformed black hole in an adiabatically evolving binary, motivated by various astrophysical settings including disk dynamics and extreme mass-ratio inspirals. As the tidal-field strength is increased, initially regular, bound geodesics undergo four stages: (i) weak chaos emerges within the bound motion; (ii) a subset of trajectories plunges into the black hole; (iii) a fraction of the remaining trajectories becomes unbound; and (iv) no bound trajectories persist. We provide semi-analytic estimates for the critical tidal amplitudes associated with each transition. Our estimates, within the idealized test-particle description, indicate that, within the frequency band of ground-based gravitational-wave detectors, the matter flow around black holes may already be depleted, whereas LISA and (B-)DECIGO could probe the earlier stages. Our results suggest that an object orbiting a tidally deformed massive black hole may remain near resonances in a long term, indicating an accumulated, non-negligible impact on the gravitational-wave phase. Another finding is that tidal perturbations can modulate nonlinear couplings among epicyclic oscillations of geodesics, and could therefore, in principle, affect resonant excitation mechanism potentially relevant to quasi-periodic oscillations in X-ray light curves from accreting black holes.

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 / 1 minor

Summary. The manuscript examines the geometry of tidally deformed rotating black holes and the motion of timelike geodesics in their vicinity within the relativistic restricted three-body problem. It identifies four stages of evolution for initially regular bound geodesics as the tidal field strength increases: (i) emergence of weak chaos, (ii) plunging into the black hole, (iii) becoming unbound, and (iv) complete depletion of bound trajectories. Semi-analytic estimates for the critical tidal amplitudes at each transition are provided, with discussions on implications for gravitational-wave observations in different detector bands and for quasi-periodic oscillations in accreting black holes.

Significance. If the results hold within the stated approximations, the work offers a local picture of structural evolution in binaries involving black holes, potentially relevant to extreme mass-ratio inspirals and disk dynamics. The provision of semi-analytic estimates for critical amplitudes is a notable strength, allowing for concrete predictions about when bound motion persists or depletes. This could inform interpretations of gravitational-wave signals and X-ray light curves from black hole systems.

major comments (1)
  1. [Abstract] Abstract: the four-stage sequence and semi-analytic critical amplitudes are derived entirely within the test-particle limit on a static (or adiabatically frozen) tidally deformed background. No quantitative threshold (e.g., mass-ratio or inspiral-time-scale bound) is supplied at which the no-backreaction and slow-evolution assumptions fail, which is load-bearing for the applicability claims to LIGO and LISA bands.
minor comments (1)
  1. [Abstract] Abstract: the abstract mentions 'semi-analytic estimates' but does not specify the method or validation approach used to derive the critical amplitudes.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the careful reading and constructive feedback. The major comment highlights an important point about the regime of validity of our test-particle analysis. We address it below and have revised the manuscript to strengthen the discussion of applicability without extending the scope beyond the geodesic problem.

read point-by-point responses
  1. Referee: [Abstract] Abstract: the four-stage sequence and semi-analytic critical amplitudes are derived entirely within the test-particle limit on a static (or adiabatically frozen) tidally deformed background. No quantitative threshold (e.g., mass-ratio or inspiral-time-scale bound) is supplied at which the no-backreaction and slow-evolution assumptions fail, which is load-bearing for the applicability claims to LIGO and LISA bands.

    Authors: We agree that explicit quantitative thresholds would better support the applicability statements. Our framework is deliberately limited to timelike geodesics on a fixed, adiabatically deformed background in order to isolate the geometric and dynamical effects of tidal deformation. Determining precise mass-ratio or timescale bounds at which backreaction or non-adiabatic evolution invalidates the approximation would require a self-consistent radiation-reaction calculation, which lies outside the present scope. We have added a dedicated paragraph in the Discussion section that supplies order-of-magnitude estimates drawn from the EMRI literature: the adiabatic approximation remains valid for mass ratios q ≲ 10^{-4} over timescales of many orbital periods, while backreaction on the background is negligible for the local geodesic dynamics considered here. We have also revised the abstract and introduction to qualify the detector-band statements as applying within the test-particle, adiabatic limit, thereby clarifying that the LIGO-band depletion claim is indicative rather than quantitative for comparable-mass systems. revision: partial

Circularity Check

0 steps flagged

No circularity: semi-analytic critical amplitudes derived from geodesic integration on fixed deformed metric

full rationale

The four-stage sequence and critical tidal amplitudes are obtained by direct numerical integration of timelike geodesics in an explicitly constructed tidally perturbed metric (test-particle limit, adiabatically frozen background). No step reduces a claimed prediction to a fitted parameter taken from the same data set, nor does any load-bearing premise collapse to a self-citation whose content is itself unverified. The test-particle and slow-evolution assumptions are stated as modeling choices, not derived from the paper's own equations. The derivation chain therefore remains self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

0 free parameters · 3 axioms · 0 invented entities

The central claim rests on standard general-relativistic geodesic motion in a tidally perturbed rotating black-hole metric under the test-particle and adiabatic-evolution assumptions.

axioms (3)
  • standard math Timelike geodesics govern test-particle motion in the deformed spacetime
    Invoked throughout the description of bound, plunging, and unbound trajectories.
  • domain assumption Test-particle limit with no back-reaction
    Small orbiting object does not alter the background metric.
  • domain assumption Adiabatic evolution of the binary
    Binary parameters change slowly relative to orbital timescales.

pith-pipeline@v0.9.0 · 5563 in / 1387 out tokens · 62150 ms · 2026-05-16T12:14:37.691687+00:00 · methodology

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Works this paper leans on

136 extracted references · 136 canonical work pages · 51 internal anchors

  1. [1]

    Astrophysical implications 10 A

    Effective potential 7 2.ϵ − c : from bound phase to chaotic phase 8 3.ϵ + c : from chaotic phase to collapsing phase 9 4.ϵ 0 c: from collapsing phase to depleted phase 10 V. Astrophysical implications 10 A. Structural evolution of accretion disks 10 B. EMRIs in a tidal environment 11 C. Imprints on GW observations 11 VI. Summary 12 Acknowledgments 13 A. T...

  2. [2]

    Background null tetrad 13

  3. [3]

    Reconstruction of a tidally deformed metric 15

    Stationary tidal perturbations 14 B. Reconstruction of a tidally deformed metric 15

  4. [4]

    The relativistic restricted three-body problem: geometry and motion around tidally perturbed black holes

    Metric reconstruction 15 C. Tidally deformed Schwarzschild metric 17 References 18 I. INTRODUCTION Gravitational-wave (GW) astronomy paved a new way to look at the Universe, and provides a unique and exquisite probe of black holes (BHs) in the strong-field regime of General Relativity (GR) [1–6]. The com- ing decades will witness higher sensitivity detect...

  5. [5]

    1− r+ rSch + 2ˆL2 0 r2 Sch 1− r+ 2rSch − r2 + 4r2 Sch # , whereλ pl is the value of the affine parameter at the onset of plunge and the subscript, “Sch

    Effective potential The metric of a tidally deformed Schwarzschild BH is provided in Appendix C. Following the manner of Ref. [16], we obtain the equation of motion foru r: −(u r)2 + ˆE2 −V= 0,(18) 8 where V= 1− r+ r 1 + ˆL2 r2 ! −ϵ(1 + 3 cos 2φ) 1− r+ r (19) × " 2r(r−r +) + ˆL2 r2 4r2 −2r +r−r 2 + # . This recovers Eq. (23) of Cardoso and Foschi [16] by ...

  6. [6]

    × 10-5 L 0/r+ ϵc - E=0.96 E=0.97 E=0.98 E=0.99 2.0 2.5 3.0 3.5

  7. [7]

    × 10-5 L 0/r+ ϵc + 2.0 2.5 3.0 3.5

  8. [8]

    evaporation

    × 10-5 L 0/r+ ϵc0 FIG. 6:Left:ϵ − c given in Eq. (29) for various sets of ( ˆE, ˆL0). The curves correspond to ˆE= 0.96 (blue dashed), ˆE= 0.97 (purple dot-dashed), ˆE= 0.98 (orange dotted), ˆE= 0.99 (red solid), respectively.Middle:ϵ + c given in Eq. (33) for the same set of ( ˆE, ˆL0) as in the left panel.Right:ϵ 0 c given in Eq. (35). Note that, given...

  9. [9]

    Background null tetrad We analyze tidal perturbations within the Newman- Penrose formalism [109, 110]. First, let us introduce two real null vectors,{l,n}, and two complex null vectors, {m, m}, where mis the complex conjugate ofm, subject to [109] lµlµ =n µnµ =m µmµ = mµmµ = 0, lµnµ =−1, m µmµ = 1,(A1) lµmµ =l µmµ =n µmµ =n µmµ = 0. The set of these vecto...

  10. [10]

    In a binary system with large separation, the characteristic length scale of the ex- ternal universe,R, is much larger thanM, i.e.,M≪ R

    Tidal moments We introduce the notion of gravitoelectric tidal mo- ments, which encode information of an external gravi- tational source approximately. In a binary system with large separation, the characteristic length scale of the ex- ternal universe,R, is much larger thanM, i.e.,M≪ R. In the region ofr≪ R, tidal deformations are de- scribed within full...

  11. [11]

    Stationary tidal perturbations Tidal perturbations are governed by the Teukolsky equations [115, 116]. The solution withs= +2 is de- composed as ψ0 = X ℓm αℓmR+2 ℓm(r)Y +2 ℓm .(A12) Note that, since our interest is in a slowly-varying tidal perturbation, the spin-weighted spheroidal harmonics re- duce toY +2 ℓm . Following the manner of Ref. [106], we ob-...

  12. [12]

    Hertz potential Reconstruction of a tidally deformed metric consists of two parts: (i) deriving a potential – referred to as a Hertz potential – from the Weyl scalar and (ii) acting a certain differential operator on the potential, thereby ob- taining a metric perturbation that shares physically same information with the Weyl scalar used in the reconstruc...

  13. [13]

    1−2 M r 2# 0 0 0 0−r 4 sin2 θ

    Metric reconstruction Before introducing the operator generating a metric perturbation from Ψ, we adopt the ingoing-radiation gauge on the metric perturbationh µν [103, 104] lµhµν = 0, g µνhµν = 0.(B4) The Geroch, Held, and Penrose (GHP) operator,S µν, al- lows us to generate a metric perturbation from the Hertz potential (B3) via [119] hµν = 4Re S † µνΨ ...

  14. [14]

    B. P. Abbottet al.(LIGO Scientific, Virgo), Phys. Rev. Lett.116, 221101 (2016), [Erratum: Phys.Rev.Lett. 121, 129902 (2018)], arXiv:1602.03841 [gr-qc]

  15. [15]

    Testing the nature of dark compact objects: a status report

    V. Cardoso and P. Pani, Living Rev. Rel.22, 4 (2019), arXiv:1904.05363 [gr-qc]

  16. [16]

    Tests of General Relativity with GWTC-3

    R. Abbottet al.(LIGO Scientific, VIRGO, KAGRA), Phys. Rev. D112, 084080 (2025), arXiv:2112.06861 [gr- qc]

  17. [17]

    A. G. Abacet al.(LIGO Scientific, Virgo, KAGRA), Phys. Rev. Lett.135, 111403 (2025), arXiv:2509.08054 [gr-qc]

  18. [18]

    Black hole spectroscopy: from theory to experiment

    E. Bertiet al., (2025), arXiv:2505.23895 [gr-qc]

  19. [19]

    Cardoso, S

    V. Cardoso, S. Biswas, and S. Sarkar (2025) arXiv:2511.14841 [gr-qc]

  20. [21]

    Branchesiet al., JCAP07, 068 (2023), arXiv:2303.15923 [gr-qc]

    M. Branchesiet al., JCAP07, 068 (2023), arXiv:2303.15923 [gr-qc]

  21. [22]

    A. J. Dittmann, A. M. Dempsey, and H. Li, Astrophys. J.964, 61 (2024), arXiv:2310.03832 [astro-ph.HE]

  22. [23]

    Yang, W.-B

    S.-C. Yang, W.-B. Han, H. Tagawa, S. Li, Y. Jiang, P. Shen, Q. Yun, C. Zhang, and X.-Y. Zhong, Astro- phys. J. Lett.988, L41 (2025), arXiv:2401.01743 [astro- ph.HE]

  23. [24]

    A. G. Abacet al.(LIGO Scientific, Virgo, KAGRA), Astrophys. J. Lett.993, L21 (2025), arXiv:2510.26931 [astro-ph.HE]

  24. [25]

    J. S. Santos, V. Cardoso, J. Nat´ ario, and M. van de Meent, Phys. Rev. Lett.135, 211402 (2025), arXiv:2506.14868 [gr-qc]

  25. [26]

    S. Naoz, C. M. Will, E. Ramirez-Ruiz, A. Hees, A. M. Ghez, and T. Do, Astrophys. J. Lett.888, L8 (2020), arXiv:1912.04910 [astro-ph.GA]

  26. [27]

    C. M. Will, S. Naoz, A. Hees, A. Tucker, E. Zhang, T. Do, and A. Ghez, Astrophys. J.959, 58 (2023), arXiv:2307.16646 [astro-ph.GA]

  27. [28]

    Straubet al.(GRAVITY), Astron

    O. Straubet al.(GRAVITY), Astron. Astrophys.672, A63 (2023), [Erratum: Astron.Astrophys. 677, C2 (2023)], arXiv:2303.04067 [astro-ph.GA]

  28. [29]

    Cardoso and A

    V. Cardoso and A. Foschi, Phys. Rev. D104, 024004 (2021), arXiv:2106.06551 [gr-qc]

  29. [30]

    Camilloni, G

    F. Camilloni, G. Grignani, T. Harmark, R. Oliveri, M. Orselli, and D. Pica, Phys. Rev. D107, 084011 (2023), arXiv:2301.04879 [gr-qc]

  30. [31]

    Tidal deformation of a slowly rotating black hole

    E. Poisson, Phys. Rev. D91, 044004 (2015), arXiv:1411.4711 [gr-qc]

  31. [32]

    Tidal deformation of a slowly rotating material body. External metric

    P. Landry and E. Poisson, Phys. Rev. D91, 104018 (2015), arXiv:1503.07366 [gr-qc]

  32. [33]

    P. Pani, L. Gualtieri, A. Maselli, and V. Ferrari, Phys. Rev. D92, 024010 (2015), arXiv:1503.07365 [gr-qc]

  33. [34]

    D. C. Robinson, Phys. Rev. Lett.34, 905 (1975)

  34. [35]

    Carter, Phys

    B. Carter, Phys. Rev. Lett.26, 331 (1971)

  35. [36]

    S. W. Hawking, Commun. Math. Phys.25, 152 (1972)

  36. [37]

    J. D. Bekenstein, in2nd International Sakharov Con- ference on Physics(1996) pp. 216–219, arXiv:gr- qc/9605059

  37. [38]

    Has the black hole equilibrium problem been solved?

    B. Carter, in8th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation and Relativistic Field Theories (MG 8)(1997) pp. 136–155, arXiv:gr-qc/9712038

  38. [39]

    P. T. Chrusciel, J. Lopes Costa, and M. Heusler, Living Rev. Rel.15, 7 (2012), arXiv:1205.6112 [gr-qc]

  39. [40]

    Testing the black hole "no-hair" hypothesis

    V. Cardoso and L. Gualtieri, Class. Quant. Grav.33, 174001 (2016), arXiv:1607.03133 [gr-qc]

  40. [41]

    Poisson, Phys

    E. Poisson, Phys. Rev. D70, 084044 (2004), arXiv:gr- qc/0407050

  41. [42]

    Nonrotating black hole in a post-Newtonian tidal environment

    S. Taylor and E. Poisson, Phys. Rev. D78, 084016 (2008), arXiv:0806.3052 [gr-qc]

  42. [43]

    Tidal heating and torquing of a Kerr black hole to next-to-leading order in the tidal coupling

    K. Chatziioannou, E. Poisson, and N. Yunes, Phys. Rev. D87, 044022 (2013), arXiv:1211.1686 [gr-qc]

  43. [44]

    Katagiri,https://github.com/TakuyaKatagiri/ Tidally_Deformed_metric(2026)

    T. Katagiri,https://github.com/TakuyaKatagiri/ Tidally_Deformed_metric(2026)

  44. [45]

    Katagiri and V

    T. Katagiri and V. Cardoso,https:// the-center-of-gravity.com/data-and-routines/ (2026)

  45. [46]

    W. M. Kinnersley,Type D gravitational fields, Ph.D. thesis, Caltech (1968)

  46. [47]

    Geometry and dynamics of a tidally deformed black hole

    E. Poisson and I. Vlasov, Phys. Rev. D81, 024029 (2010), arXiv:0910.4311 [gr-qc]

  47. [48]

    Relativistic theory of tidal Love numbers

    T. Binnington and E. Poisson, Phys. Rev. D80, 084018 (2009), arXiv:0906.1366 [gr-qc]

  48. [49]

    H. S. Chia, Phys. Rev. D104, 024013 (2021), arXiv:2010.07300 [gr-qc]

  49. [50]

    Charalambous, S

    P. Charalambous, S. Dubovsky, and M. M. Ivanov, JHEP05, 038 (2021), arXiv:2102.08917 [hep-th]

  50. [51]

    Poisson, Phys

    E. Poisson, Phys. Rev. D104, 104062 (2021), 19 arXiv:2108.07328 [gr-qc]

  51. [52]

    S. E. Gralla, Class. Quant. Grav.35, 085002 (2018), arXiv:1710.11096 [gr-qc]

  52. [53]

    Poisson, Phys

    E. Poisson, Phys. Rev. D103, 064023 (2021), arXiv:2012.10184 [gr-qc]

  53. [54]

    Katagiri, K

    T. Katagiri, K. Yagi, and V. Cardoso, Phys. Rev. D 111, 084080 (2025), arXiv:2409.18034 [gr-qc]

  54. [55]

    Katagiri, V

    T. Katagiri, V. Cardoso, T. Ikeda, and K. Yagi, Phys. Rev. D111, 084081 (2025), arXiv:2410.02531 [gr-qc]

  55. [56]

    J. M. Bardeen, W. H. Press, and S. A. Teukolsky, As- trophys. J.178, 347 (1972)

  56. [57]

    Contopoulos,Order and chaos in dynamical astron- omy(2002)

    G. Contopoulos,Order and chaos in dynamical astron- omy(2002)

  57. [58]

    J. R. Gair, C. Li, and I. Mandel, Phys. Rev. D77, 024035 (2008), arXiv:0708.0628 [gr-qc]

  58. [59]

    The non-integrability of the Zipoy-Voorhees metric

    G. Lukes-Gerakopoulos, Phys. Rev. D86, 044013 (2012), arXiv:1206.0660 [gr-qc]

  59. [60]

    Destounis and P

    K. Destounis and P. G. S. Fernandes, (2025), arXiv:2508.20191 [gr-qc]

  60. [61]

    The Astrophysics of Resonant Orbits in the Kerr Metric

    J. Brink, M. Geyer, and T. Hinderer, Phys. Rev. D91, 083001 (2015), arXiv:1501.07728 [gr-qc]

  61. [62]

    Celestial mechanics in Kerr spacetime

    W. Schmidt, Class. Quant. Grav.19, 2743 (2002), arXiv:gr-qc/0202090

  62. [63]

    Spacetime Encodings II - Pictures of Integrability

    J. Brink, Phys. Rev. D78, 102002 (2008), arXiv:0807.1179 [gr-qc]

  63. [64]

    V. I. Arnold,Mathematical Methods of Classical Me- chanics, Graduate Texts in Mathematics (Springer, 1989)

  64. [65]

    Laskar, Celestial Mechanics and Dynamical Astron- omy56, 191 (1993)

    J. Laskar, Celestial Mechanics and Dynamical Astron- omy56, 191 (1993)

  65. [66]

    Poincar´ e, Rendiconti del Circolo Matematico di Palermo (1884-1940)33, 375 (1912)

    H. Poincar´ e, Rendiconti del Circolo Matematico di Palermo (1884-1940)33, 375 (1912)

  66. [67]

    G. D. Birkhoff, Transactions of the American Mathe- matical Society14, 14 (1913)

  67. [68]

    An observable signature of a background deviating from Kerr

    G. Lukes-Gerakopoulos, T. A. Apostolatos, and G. Contopoulos, Phys. Rev. D81, 124005 (2010), arXiv:1003.3120 [gr-qc]

  68. [69]

    T. A. Apostolatos, G. Lukes-Gerakopoulos, and G. Contopoulos, Phys. Rev. Lett.103, 111101 (2009), arXiv:0906.0093 [gr-qc]

  69. [70]

    Orbital resonances around Black holes

    J. Brink, M. Geyer, and T. Hinderer, Phys. Rev. Lett. 114, 081102 (2015), arXiv:1304.0330 [gr-qc]

  70. [71]

    A Periodic Table for Black Hole Orbits

    J. Levin and G. Perez-Giz, Phys. Rev. D77, 103005 (2008), arXiv:0802.0459 [gr-qc]

  71. [72]

    Gueron and P

    E. Gueron and P. S. Letelier, (2001), arXiv:astro- ph/0108042

  72. [73]

    Teo, Gen

    E. Teo, Gen. Rel. Grav.53, 10 (2021), arXiv:2007.04022 [gr-qc]

  73. [74]

    Carter, Phys

    B. Carter, Phys. Rev.174, 1559 (1968)

  74. [75]

    R. V. Wagoner, Phys. Rept.311, 259 (1999), arXiv:astro-ph/9805028

  75. [76]

    M. A. Abramowicz and W. Kluzniak, Astron. Astro- phys.374, L19 (2001), arXiv:astro-ph/0105077

  76. [77]

    The physics of kHz QPOs---strong gravity's coupled anharmonic oscillators

    W. Kluzniak and M. A. Abramowicz, (2001), arXiv:astro-ph/0105057

  77. [78]

    M. A. Abramowicz and P. C. Fragile, Living Rev. Rel. 16, 1 (2013), arXiv:1104.5499 [astro-ph.HE]

  78. [79]

    Ingram and S

    A. Ingram and S. Motta, New Astron. Rev.85, 101524 (2019), arXiv:2001.08758 [astro-ph.HE]

  79. [80]

    Horak, inWorkshop on Processes in the Vicinity of Black Holes and Neutron Stars(2004) arXiv:astro- ph/0408092

    J. Horak, inWorkshop on Processes in the Vicinity of Black Holes and Neutron Stars(2004) arXiv:astro- ph/0408092

  80. [81]

    Internal resonance in non-linear disk oscillations and the amplitude evolution of neutron star kilohertz QPOs

    J. Hor´ ak, M. A. Abramowicz, W. Klu´ zniak, P. Rebusco, and G. T¨ or¨ ok, Astronomy and Astrophysics499, 535 (2009), arXiv:0901.3076 [astro-ph.CO]

Showing first 80 references.