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Quantum black holes split: one kills QPOs, one keeps them

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2026-08-04 20:15 UTC pith:U3JYOE6A

load-bearing objection A carefully done analytic and numerical study of QPOs in two quantum-corrected Schwarzschild-like metrics, but the observational claim is not established because the model is non-rotating while the comparison sources spin rapidly. the 4 major comments →

arxiv 2509.08674 v2 pith:U3JYOE6A submitted 2025-09-10 astro-ph.HE gr-qc

Analytic and Numerical Constraints on QPOs in EHT and XRB Sources Using Quantum-Corrected Black Holes

Ahmad Al-Badawi , Faizuddin Ahmed , Orhan Donmez , Fatih Dogan , Behnam Pourhassan , \.Izzet Sakall{\i} , Yassine Sekhmani This is my paper
classification astro-ph.HE gr-qc MSC 83C5783C10
keywords quantum-corrected black holesquasi-periodic oscillationsBondi-Hoyle-Lyttleton accretionepicyclic frequenciesX-ray binariesEvent Horizon Telescopemodified gravityaccretion shock cone
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

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

Two quantum-corrected black hole spacetimes that look identical at the horizon nevertheless produce opposite observable timing behavior, the paper argues. In Model-I, where both time and space metric components carry quantum corrections proportional to a dimensionless parameter ζ, the innermost stable circular orbit shifts outward by ζ⁴/(81M³) and the Bondi-Hoyle-Lyttleton stagnation point migrates from about 27M to 5M, shrinking the shock-cone cavity and suppressing quasi-periodic oscillations entirely for ζ ≥ 3M. In Model-II, where only the spatial component is corrected, the ISCO stays at 6M and the stagnation point stays near 26.8M, so low-frequency QPOs remain stable up to ζ ≥ 5M. The simulated power spectra show 3:2, 2:1, and 5:3 frequency ratios matching GRS 1915+105, XTE J1550-564, and GX 339-4, and the numerically derived ceiling ζ ≲ 4M lines up with Event Horizon Telescope shadow limits on M87* and Sgr A*. If correct, X-ray timing becomes a direct probe of quantum gravity parameters in black hole accretion.

Core claim

On its own terms, the paper's discovery is that the two quantum-corrected metrics are observationally distinguishable through QPO survival and frequency evolution. Model-I, with f(r) = g(r) = 1 − 2M/r + (ζ²/r²)(1 − 2M/r)², modifies both temporal and radial components; the paper derives r_ISCO = 6M + ζ⁴/(81M³) + O(ζ⁶) and shows numerically that the shock-cone stagnation point plunges from ~27M to ~5M as ζ grows, with mass accretion down by up to ~95% and QPOs absent for ζ ≥ 3M. Model-II, with f(r) Schwarzschild and only g(r) quantum-corrected, keeps νφ = νθ exactly Keplerian, factorizes the radial frequency as (2πν_r)² = M(r − 6M)(ζ²(r − 2M) + r³)/r⁷, and leaves the ISCO at exactly 6M; the st

What carries the argument

The stagnation point of the Bondi-Hoyle-Lyttleton shock cone: the radius inside the cone where the radial velocity changes sign, bounding the cavity that traps oscillatory modes. Its ζ-dependent position — migrating from 27M to 5M in Model-I, fixed near 26.8M in Model-II — determines whether QPO modes survive or are suppressed. The analytic support comes from epicyclic frequencies derived from the effective potential, with the zero of the radial frequency defining the ISCO: in Model-I that zero moves at order ζ⁴, while in Model-II it factorizes to remain at 6M for all ζ.

Load-bearing premise

The numerical results assume a non-spinning black hole, while the X-ray binaries used for comparison spin rapidly; if rotation changes the stagnation-point behavior or QPO suppression threshold, the ζ constraints could shift.

What would settle it

A long-term X-ray monitoring campaign on Sgr A* that finds no coherent ~78.6/115.9 µHz pair — the Model-I 3:2 doublet predicted at ζ ≈ 1M — would contradict the paper's mapping; likewise, observing a stable 3:2 HFQPO pair in a system whose inferred ζ exceeds ~3M would falsify Model-I's suppression threshold.

Watch this falsifier. Get emailed when new claim-graph text bears on it.

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If this is right

  • If Model-I is right, detections of high-frequency QPOs in stellar-mass black holes would push ζ below roughly 3M, while persistently non-variable accreting sources could be signatures of strong quantum corrections.
  • If Model-II is right, QPO ratios alone cannot fix ζ because the Keplerian azimuthal frequency is unchanged; the model's observable handle is instead the slow enhancement of shock compression and infall speed with ζ.
  • The predicted Sgr A* microhertz and M87* nanohertz doublets preserve the same 3:2 and 2:1 ratios, giving long-baseline X-ray monitoring campaigns a specific target to confirm or reject the quantum-correction mapping.
  • The hydrodynamic ceiling ζ ≲ 4M agrees with EHT shadow bounds, meaning timing and imaging observations could jointly constrain the same quantum parameter rather than independent ones.
  • The two models' differing QPO suppression thresholds offer a direct observational way to tell whether quantum corrections enter the time-time or only the space-space part of the metric.

Where Pith is reading between the lines

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

  • The comparison sources rotate significantly while the simulated spacetimes are static and spherically symmetric; if rotation alters the stagnation-point trajectory or cavity stability, the claimed ζ bounds could shift. The paper leaves this as future work.
  • The persistent 3:2, 2:1, and 5:3 ratios in both models may be generic features of any spherical metric with νθ = νφ degeneracy, so the ratios themselves may not uniquely identify these quantum-corrected spacetimes; the suppression threshold and stagnation migration are more distinctive.
  • A testable extension is to run the same BHL plus power-spectral pipeline on rotating quantum-corrected metrics to see whether the ζ ≥ 3M QPO suppression survives; that would determine whether the stellar-mass constraints are robust.
  • The agreement between the shadow-derived and accretion-derived ζ ceilings could partly reflect that both probes respond to near-horizon geometric focusing; combined shadow-plus-timing fits may overconstrain ζ if the two channels are not truly independent.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

4 major / 5 minor

Summary. The paper studies two spherically symmetric, quantum-corrected black-hole spacetimes (Model-I and Model-II) that reduce to Schwarzschild when ζ→0. For each model it derives epicyclic frequencies, the ISCO location, and periastron precession, and then presents Bondi-Hoyle-Lyttleton accretion simulations and PSD analyses, claiming that Model-I suppresses QPOs for ζ≳3M and that characteristic frequency ratios 3:2, 2:1, 5:3 match X-ray binaries such as GRS 1915+105, XTE J1550-564 and GX 339-4. The paper further states that hydrodynamically derived constraints ζ≲4M agree with EHT shadow constraints on M87* and Sgr A* from Ref. [23], and it rescales the QPO frequencies to predict microhertz and nanohertz variability for those two supermassive black holes.

Significance. If the central claims were established, the paper would provide an interesting two-model comparison for quantum-gravity phenomenology: a clean analytic separation between a model with an O(ζ^4) ISCO shift and a model with an exactly fixed ISCO, plus a numerical suggestion that the stagnation point in BHL accretion controls the QPO cavity. The analytic derivations of the epicyclic frequencies and the factorization in Model-II are transparent and, in the Schwarzschild limit, reduce correctly; the perturbative ISCO shift r_ISCO^(I) = 6M + ζ^4/(81M^3) is a concise and useful result. The manuscript also gives specific, falsifiable frequency ratios for future observations. However, the observational claims rest on a static, non-rotating model applied to rapidly spinning X-ray binaries and on PSD peak selection that is not statistically controlled; the numerical constraints are not reproducible from the information provided. These issues are central rather than cosmetic, so the current significance is conditional on the concerns below being resolved.

major comments (4)
  1. [Sec. 4.3, 5.2; Table 2; Sec. 6] The QPO comparison with X-ray binaries assumes spin independence without any supporting test. All simulations and PSD analyses use the static, spherically symmetric metrics (2)–(3), while the comparison sources GRS 1915+105, XTE J1550-564 and GX 339-4 are rapidly spinning (e.g., GRS 1915+105 with a≈0.98). In Kerr spacetime the ISCO, the epicyclic frequencies, and the frequency ratios change substantially with spin; the paper explicitly leaves rotating QCBHs for future work in Sec. 6. The claim that the computed non-rotating frequency ratios and the ζ≥3M suppression threshold are consistent with observations is therefore not established. A concrete test would be to repeat the epicyclic analysis for a rotating generalization of Model-I, or to show that spin does not affect the relevant ratios.
  2. [Sec. 4.3.1, 4.3.2; Figs. 16, 18, 19] The identification of 3:2, 2:1, and 5:3 frequency ratios appears post hoc. The PSDs contain many peaks (e.g., in Fig. 16 for ζ=1M the labeled peaks are 3.7, 10.2, 16.7, 27, 32.6, 38.1, 45.3, 48.1 Hz), and the authors select pairs such as 48.1:32.6 and 32.6:16.7 while other pairs are ignored. No statistical measure (e.g., false-alarm probability, peak significance, or a pre-specified selection criterion) is given, and the 0–7% error margin is stated only for the chosen pairs. With 5–8 peaks per PSD, near-commensurate ratios among random pairs are expected; the claimed agreement with GRS 1915+105, XTE J1550-564, and GX 339-4 is therefore not robust evidence for the models.
  3. [Sec. 4, 4.1, 4.3; Data Availability] The numerical constraints are not reproducible from the manuscript. Section 4 states that general-relativistic hydrodynamic equations are solved with HRSC and adaptive mesh refinement, but it does not specify the numerical scheme, the reconstruction method, the Riemann solver, the grid resolution, the computational domain, the boundary conditions, or the initial BHL parameters (density, velocity, sound speed, adiabatic index). The PSD analysis is also described only qualitatively. The Data Availability statement says the datasets are not publicly available. Given that the central quantitative claims—QPO suppression for ζ≥3M in Model-I, the stagnation-point curve in Fig. 13, and the constraint ζ≲4M—are derived from these simulations, the lack of reproducibility is a load-bearing deficiency. At minimum, a convergence study and a detailed numerical setup description are required.
  4. [Sec. 4.1.1, 4.2, 5.1] There is an internal contradiction about the photon sphere in Model-I. In Sec. 4.1.1 the paper states that the photon impact parameter b_ph shrinks with ζ while the photon sphere radius r_ph remains fixed at 3M; this is consistent with Eq. (2). However, Sec. 4.2 says 'in Model-I the photon sphere contracts slightly while the ISCO moves outward,' and Sec. 5.1 says that the decrease in b_ph indicates 'the photon sphere approaches the BH horizon.' The latter statements conflate the photon-sphere radius with the critical impact parameter and contradict the earlier exact statement. Since the agreement with EHT constraints in Sec. 5.1 is presented as a validation of the model, this inconsistency needs to be corrected and the distinction between r_ph and b_ph maintained throughout.
minor comments (5)
  1. [Abstract; Sec. 2] The abstract calls ζ a dimensionless parameter, but the metric functions in Eqs. (2)–(3) require ζ to have dimensions of length, and the tables/figures use ζ/M. Please make the dimensional status consistent.
  2. [Eqs. (25)–(26), Fig. 4] The text notes that νθ=νϕ in Model-I, but Fig. 4 plots νθ and νϕ as separate curves. Please clarify whether the two curves coincide exactly and consider a single label.
  3. [Sec. 4.3.1] The transition from QPOs at ζ<3M to 'strongly stable' behavior at ζ≥3M is stated without a quantitative criterion for what constitutes a QPO. Please specify how peaks are identified above the noise and how the suppression threshold is defined.
  4. [Sec. 5.1; Fig. 20] The phrase 'remarkable agreement' is overstated: the numerical constraint ζ≲4M from accretion suppression is a qualitative threshold, not a formal bound with uncertainty, and the EHT limits (ζ≤4.7M for M87* and ζ≤3.52M for Sgr A*) are themselves model-dependent. A more cautious wording would better match the actual evidence.
  5. [Throughout] There are frequent typographical artifacts such as 'efficient' and inconsistent hyphenation; a careful proofreading pass is needed.

Circularity Check

0 steps flagged

No significant circularity: analytic frequencies are derived from an externally sourced metric, numerical BHL simulations are independent, and EHT limits come from a separate paper.

full rationale

The derivation chain is self-contained. The metrics (Eqs. 2-3) are attributed to the independent paper [49]; the epicyclic frequencies and ISCO shifts (Eqs. 25-30) are obtained by direct algebra from those metrics, not from the QPO observations. The numerical BHL simulations use the same spacetime metric as an input but solve the relativistic hydrodynamic equations from scratch; the PSD peaks are outputs of the simulation, not inputs, and zeta is never fitted to any observed QPO frequency. Observational comparisons are qualitative: the paper lists discrete ratios (3:2, 2:1, 5:3) and reports 0-7% errors, but no parameter is adjusted to force agreement. The EHT-based constraints (zeta <= 4.7M for M87* and zeta <= 3.52M for Sgr A*) come from Chen & Yang 2025 [23], which has no author overlap with the present paper, so the agreement with the hydrodynamically inferred zeta ~ 4M is an independent cross-check. Self-citations ([67], [70]-[73]) concern numerical methods and the standard shock-cone QPO mechanism; they are not load-bearing because the QPO frequencies are computed from the present simulations and the analytic frequencies are derived here. The main limitation—the assumption of spherical symmetry while comparing to spinning XRBs, acknowledged in Sec. 6 ('Future investigations should focus on extending these results to rotating QCBHs')—is a scope/correctness risk about spin-independence, not a circularity.

Axiom & Free-Parameter Ledger

2 free parameters · 4 axioms · 0 invented entities

The central claims rest on two model parameters (zeta and M), on the validity of the quantum-corrected metrics, and on a heuristic link between stagnation point and QPO cavity. No new particles or forces are introduced.

free parameters (2)
  • zeta = varied from 0 to 8M
    The quantum correction length scale in the metric (Eq. 2 and 3). The paper varies it to make predictions and to compare with EHT limits; it is not derived from first principles.
  • M = 10 M_sun
    Fiducial mass used to convert frequencies to Hz; the paper extrapolates to other masses by scaling.
axioms (4)
  • domain assumption Spacetime metric functions (Eq. 2 and 3) are valid quantum-corrected black hole solutions.
    Taken from Refs. [49,23]; the paper assumes these represent physical quantum gravity effects.
  • standard math Linear epicyclic approximation is valid for QPOs in accretion disks.
    Standard treatment of small perturbations around circular orbits (Section 3.2).
  • domain assumption BHL accretion flow around a non-rotating BH produces QPOs comparable to those from real XRBs.
    The paper uses this to connect simulations to observations (Section 4).
  • ad hoc to paper The stagnation point inside the shock cone determines the QPO cavity size.
    This is the paper's own interpretation (Section 4.2) and is not established from first principles.

pith-pipeline@v1.3.0-alltime-deepseek · 35309 in / 12966 out tokens · 126795 ms · 2026-08-04T20:15:22.484830+00:00 · methodology

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Cite this review

Pith. "Pith review of Analytic and Numerical Constraints on QPOs in EHT and XRB Sources Using Quantum-Corrected Black Holes." pith.science (2026). https://pith.science/paper/U3JYOE6A

@misc{pith2026250908674,
  author       = {Pith},
  title        = {Pith review of: Analytic and Numerical Constraints on QPOs in EHT and XRB Sources Using Quantum-Corrected Black Holes},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/U3JYOE6A}},
  note         = {Machine review of arXiv:2509.08674}
}
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read the original abstract

This investigation examines QPOs in two quantum-corrected BH spacetimes that preserve general covariance while incorporating quantum gravitational effects through a dimensionless parameter \zeta. We combine analytical derivations of epicyclic frequencies with comprehensive numerical simulations of BHL accretion to explore how quantum corrections manifest in observable astrophysical phenomena. Using a fiducial BH mass of M=10M_\odot representative of stellar-mass X-ray binaries, we demonstrate that the two models exhibit fundamentally different behaviors: Model-I modifies both temporal and radial metric components, leading to innermost stable circular orbit migration proportional to \zeta^4 and dramatic stagnation point evolution from 27M to 5M as quantum corrections strengthen. Model-II preserves the classical temporal component while altering only spatial geometry, maintaining constant stagnation points and stable cavity structures throughout the parameter range. Our numerical simulations reveal distinct QPO generation mechanisms, with Model-I showing systematic frequency evolution and cavity shrinkage that suppresses oscillations for \zeta \geq 3M, while Model-II maintains stable low-frequency modes up to \zeta \geq 5M. Power spectral density analyzes demonstrate characteristic frequency ratios (3:2, 2:1, 5:3) consistent with observations from X-ray binaries, providing specific targets for discriminating between quantum correction scenarios. The hydrodynamically derived constraints (\zeta \lesssim 4M) show remarkable agreement with independent EHT limits for M87* and Sgr A*, validating our theoretical framework through multiple observational channels. These results establish QPO frequency analysis as a probe for detecting quantum gravitational effects in astrophysical BHs and demonstrate the complementary nature of timing and imaging observations in constraining fundamental physics.

Figures

Figures reproduced from arXiv: 2509.08674 by Ahmad Al-Badawi, Behnam Pourhassan, Faizuddin Ahmed, Fatih Dogan, \.Izzet Sakall{\i}, Orhan Donmez, Yassine Sekhmani.

Figure 1
Figure 1. Figure 1: 3D diagrams of the quantum-corrected BH (Model-I&II) with metric function g(r), where M = 1 is fixed, and ζ ∈ {0, 2, 5} varies. Each diagram features a tan surface representing the embedding from the event horizon rh = 2.0 to r = 15, a red falling trajectory, and a red thick ring at the event horizon. The transition from a single horizon at ζ = 0 to two horizons for ζ > 0 is accompanied by a modification o… view at source ↗
Figure 2
Figure 2. Figure 2: Behavior of the effective potential using the BH model-I. Here M = 1. 6 [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Behavior of the squared of the specific angular momentum and specific energy of test particles using BH model-I. Here M = 1. An important aspect of the motion of massive test particles around a BH is the existence of the innermost stable circular orbit (ISCO). The ISCO represents the smallest radius at which a particle can maintain a stable circular orbit. Within this radius, circular orbits are no longer … view at source ↗
Figure 4
Figure 4. Figure 4: Plots for the Model-I model showing the radial, vertical and azimuthal frequencies νr,θ,ϕ against r/M for various values of the parameter ζ with M = 10M⊙. ζ = 4 and ζ = 5, the changes become dramatic, with the ISCO shifting significantly outward and the overall frequency profiles being substantially altered. The azimuthal and vertical frequencies νϕ and νθ (shown in green and cyan) remain degenerate throug… view at source ↗
Figure 5
Figure 5. Figure 5: Plots for the Model-I model showing the periastron frequency Ωp for particles orbiting a BH for various values of the parameter ζ with M = 10M⊙. ζ=0 7.5 10.0 12.5 15.0 17.5 20.0 0 1000 2000 3000 4000 r/M vr[Hz] ζ 10 20 30 40 50 ζ=0 10 20 30 40 50 -2000 -1000 0 1000 r Ωp[Hz] ζ 2 4 6 8 10 [PITH_FULL_IMAGE:figures/full_fig_p013_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Plots for the Model-II model showing the radial frequency and the periastron frequency Ωp for particles orbiting a BH for various values of the parameter ζ with M = 10M⊙. Keplerian, νϕ = νθ = (2π) −1p M/r3, and (ii) the radial frequency factorizes as (2πνr) 2 = M(r − 6M) [PITH_FULL_IMAGE:figures/full_fig_p013_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: In the Model-I case, the variation of the averaged mass accretion rate, normalized by the averaged mass accretion rate around the Schwarzschild BH, is shown as a function of ζ. The normalized mass accretion rate decreases with increasing ζ. The rate of this decrease becomes more significant as the distance from the horizon increases. Since the stagnation point moves closer to the BH with increasing ζ, the … view at source ↗
Figure 8
Figure 8. Figure 8: At r = 2.66M, the variation of the rest-mass density in the azimuthal direction has been shown for different ζ values in both the Schwarzschild and Model-I cases. It has been observed that as ζ increases, the density of the matter accreted inside the shock cone formed around the BH decreases. This decrease is particularly significant at large values of ζ. Additionally, the opening angle of the shock cone d… view at source ↗
Figure 9
Figure 9. Figure 9: This shows the variation of matter velocities around BH in a strong gravitational field at r = 2.66M for different ζ values in the Schwarzschild and Model-I cases. The plot on the left shows the variation of radial velocity along the azimuthal path, while the plot on the right shows the variation of azimuthal velocity. At the shock locations of the shock cone, the radial velocity decreases, whereas the azi… view at source ↗
Figure 10
Figure 10. Figure 10: The same analysis as in Fig.7 has been performed, but this time the ratios are shown for the Model-II case. Unlike the Model-I case given in Fig.7, the rate of decrease is much slower and follows a more linear trend. The behavior of the decrease at each radial point is similar. When compared with the Schwarzschild case, the decrease in the mass accretion rate with increasing ζ values is at most around 20%… view at source ↗
Figure 11
Figure 11. Figure 11: As in Fig.8, the variation of the rest-mass density is shown for the Schwarzschild and Model-II cases. Unlike the Model-I case, with increasing ζ values, the density of the matter trapped inside the shock cone increases, while the opening angle of the cone decreases. Similar to Model-I, the QPO modes trapped inside the cone are significantly affected by the change in the physical structure. The contrastin… view at source ↗
Figure 12
Figure 12. Figure 12: This is the same as Fig.9, but this time the azimuthal variations of radial and azimuthal velocities are shown for the Model-II case. Although the behavior differs from Model-I, it is clearly seen that these velocities undergo significant changes with increasing ζ values. The decrease in the opening angle of the cone with increasing ζ is also evident from the changes at the shock locations of the shock co… view at source ↗
Figure 13
Figure 13. Figure 13: shows the variation of rstag with respect to ζ, revealing one of the most striking differences between the two QCBH models. This comparison provides perhaps the most dramatic illustration of how different types of quantum corrections can lead to completely different physical behaviors, even when both models are derived from similar underlying principles of quantum gravity. 0 1 2 3 4 5 6 7 8 ζ/M 4 8 12 16 … view at source ↗
Figure 14
Figure 14. Figure 14: The radial variations of the radial velocities at the fixed value ϕ = 0, corresponding to the center of the resulting shock cone, are shown for different ζ values in the Model-I and Model-II models. The plot on the left shows the variation of the radial velocity for the Model-I model, confirming that the ISCO and stagnation point progressively approach the BH horizon. However, the depth remains the same f… view at source ↗
Figure 15
Figure 15. Figure 15: For the Model-I model, the variation of the mass accretion rate with respect to the quantum correction parameter ζ, along with the Schwarzschild solution, has been shown at r = 2.3M. It has been observed that as the value of ζ increases, there is a noticeable decrease in the amount of matter falling into the BH. Additionally, after reaching a steady state, cases exhibiting quasi-periodic instabilities hav… view at source ↗
Figure 16
Figure 16. Figure 16: For the Model-I model at different ζ values, PSD analyses are presented in comparison with the Schwarzschild case for M = 10M⊙, but only for the cases where quasi-periodic oscillations are observed (ζ < 3). As expected, due to the change in the physical structure of the shock cone formed around the BH with varying ζ values, the positions of the resulting QPO peaks have shifted. It has been observed that w… view at source ↗
Figure 17
Figure 17. Figure 17: The figure is the same as [PITH_FULL_IMAGE:figures/full_fig_p032_17.png] view at source ↗
Figure 18
Figure 18. Figure 18: The variation of the PSD analysis with respect to different ζ values has been compared with the Schwarzschild case, assuming the BH has a mass of M = 10M⊙, for the Model-II model. For each ζ value, it has been observed that the resulting QPO frequencies change due to the dynamic changes in the physical mechanism, and they are also excited accordingly. In other words, it has been observed that low-frequenc… view at source ↗
Figure 19
Figure 19. Figure 19: For the model in [PITH_FULL_IMAGE:figures/full_fig_p034_19.png] view at source ↗
Figure 20
Figure 20. Figure 20: This is a graphical summary of the maximum limit values obtained for the ζ parameter, based on the comparison of the critical impact parameter of photon sphere derived analytically in the Model-I case in [23] with the critical impact parameter observed by the EHT. Consistent with this, our [PITH_FULL_IMAGE:figures/full_fig_p035_20.png] view at source ↗

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Forward citations

Cited by 2 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Disformal Kerr Imprints on BHL Accretion: Shock Morphology, PSD Signatures, and Observational QPO Counterparts

    astro-ph.HE 2026-05 unverdicted novelty 5.0

    Disformal Kerr black holes in BHL accretion produce modified shock structures and QPO frequencies at 43-68 Hz and lower that align with observations from GRS 1915+105, M82 X-1, and similar sources via inverse-mass scaling.

  2. Disformal Kerr Imprints on BHL Accretion: Shock Morphology, PSD Signatures, and Observational QPO Counterparts

    astro-ph.HE 2026-05 unverdicted novelty 5.0

    Numerical BHL accretion simulations in disformal Kerr spacetime produce QPO frequencies consistent with observations from GRS 1915+105, M82 X-1, NGC 5408 X-1, and RE J1034+396.

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