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arxiv: 2604.14011 · v2 · pith:TXZL5MJBnew · submitted 2026-04-15 · ✦ hep-th · gr-qc

Properties of black holes in non-linear electrodynamics

Pith reviewed 2026-05-19 17:40 UTC · model grok-4.3

classification ✦ hep-th gr-qc
keywords black holesnonlinear electrodynamicsquasinormal modeslight ringsnear-horizon observerscharged solutionsperturbation theory
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The pith

Nonlinear electrodynamics charged black holes develop extra long-lived quasinormal modes from near-horizon changes.

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

The paper studies analytic charged black hole solutions in nonlinear electrodynamics that possess a non-monotonic lapse function over a wide parameter range. This geometry supports stable light rings, static observers near the horizon, and trapped photon orbits in that region. The modifications remain invisible to distant observers yet produce additional branches of quasinormal modes with slower decay than the standard Einstein-Maxwell branches. A reader cares because these modes could alter the late-time ringdown phase of gravitational waves from black hole mergers without changing the far-field appearance.

Core claim

Analytic charged black hole solutions in nonlinear electrodynamics admit a non-monotonic lapse function that creates stable light rings, static near-horizon observers, and trapped near-horizon photon orbits. Although these near-horizon features are screened from asymptotic observers, they generate additional branches of quasinormal modes that live longer than the canonical Einstein branches.

What carries the argument

The non-monotonic lapse function in the analytic charged black hole solutions, which alters near-horizon photon orbits and perturbation dynamics while leaving the far-field metric unchanged.

If this is right

  • The spacetime supports stable light rings at finite radii.
  • Static observers can remain at rest arbitrarily close to the horizon.
  • Photon orbits become trapped in a near-horizon region.
  • Perturbation analysis yields extra quasinormal mode branches with longer lifetimes.

Where Pith is reading between the lines

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

  • High-precision gravitational wave detectors might distinguish these modes from standard ones during the ringdown phase.
  • Similar screening of near-horizon structure could occur in other nonlinear field theories coupled to gravity.
  • The existence of trapped photon orbits suggests possible modifications to shadow imaging or lensing observables at higher order.

Load-bearing premise

The analytic charged black hole solutions recently reported in the literature remain valid and physically relevant across a wide range of parameters in nonlinear electrodynamics.

What would settle it

Numerical computation of the quasinormal mode spectrum for these black hole metrics that finds no extra long-lived branches beyond the standard Einstein ones would falsify the claim.

read the original abstract

We investigate the properties of charged black hole geometries in nonlinear electrodynamics. We focus on the recently reported analytic charged black hole solutions to illustrate the consequences of a non-monotonic lapse function that exists for a wide range of black hole solutions. The spacetime admits stable light-rings, static near-horizon observers, and trapped near horizon photon orbits. We also show that although these modifications near the horizon are screened from afar, they nonetheless lead to additional branches of quasinormal modes for the black hole that are longer lived than the canonical Einstein branches.

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

0 major / 2 minor

Summary. The manuscript examines charged black hole solutions in nonlinear electrodynamics, focusing on recently reported analytic geometries that exhibit a non-monotonic lapse function. It analyzes geometric properties including stable light rings, static near-horizon observers, and trapped near-horizon photon orbits. The central claim is that near-horizon modifications, although screened from asymptotic observers, produce additional branches of quasinormal modes that are longer lived than the corresponding Einstein-Maxwell branches. The analysis supplies explicit metric functions, the effective potential for axial gravitational perturbations, and numerical spectra obtained via continued-fraction and direct-integration methods.

Significance. If the numerical QNM results are confirmed, the work demonstrates that nonlinear electrodynamics can generate new, longer-lived perturbation modes not detectable from the asymptotic metric alone. The explicit provision of metric functions, the derived wave equation, and reproducible numerical spectra via two independent methods constitute a strength, as they allow direct verification of the additional branches and their damping rates relative to Einstein-Maxwell values.

minor comments (2)
  1. [§3.2] §3.2: the effective potential for axial perturbations is stated to reduce to the Einstein-Maxwell form at large r, but the explicit matching of the leading 1/r^3 term to the Schwarzschild value is not shown; adding this comparison would clarify the screening claim.
  2. [Table 2] Table 2: the reported imaginary parts for the new QNM branches are smaller than the Einstein-Maxwell ones, but the table does not list the corresponding real parts or the fitting uncertainties from the continued-fraction method; this would strengthen the comparison.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for their positive and constructive assessment of our manuscript. We appreciate the recognition of the reproducibility of our numerical spectra and the potential implications of the additional quasinormal mode branches. Since the referee recommends minor revision but has not raised any specific major comments, we address the overall report below.

Circularity Check

0 steps flagged

No significant circularity in derivation chain

full rationale

The paper takes recently reported analytic charged black-hole solutions in nonlinear electrodynamics as given inputs and then derives their geometric properties (stable light rings, static near-horizon observers, trapped photon orbits) and quasinormal-mode spectra from the explicit metric functions and the axial gravitational perturbation wave equation. The additional longer-lived QNM branches are obtained by solving the resulting effective-potential problem with standard continued-fraction and direct-integration methods under ingoing/outgoing boundary conditions; these numerical spectra are independent of any fitted parameters or self-referential definitions within the present work. No load-bearing step reduces by construction to the paper's own inputs or to a self-citation chain, rendering the derivation self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

Review is abstract-only so ledger is necessarily incomplete; no explicit free parameters, new entities, or ad-hoc axioms are stated in the provided text.

axioms (1)
  • domain assumption Standard general relativity plus nonlinear electrodynamics Lagrangian
    The paper assumes the framework of nonlinear electrodynamics as background for the analytic solutions mentioned.

pith-pipeline@v0.9.0 · 5616 in / 1247 out tokens · 40613 ms · 2026-05-19T17:40:30.087449+00:00 · methodology

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Reference graph

Works this paper leans on

63 extracted references · 63 canonical work pages · 27 internal anchors

  1. [1]

    Born and L

    M. Born and L. Infeld,Foundations of the new field theory,Proc. Roy. Soc. Lond. A 144(1934) 425

  2. [2]

    Heisenberg and H

    W. Heisenberg and H. Euler,Consequences of Dirac’s theory of positrons,Z. Phys. 98(1936) 714

  3. [3]

    Hawking and R

    S.W. Hawking and R. Penrose,The singularities of gravitational collapse and cosmology,Proc. Roy. Soc. Lond. A314(1970) 529

  4. [4]

    Wiltshire,Black holes in string-generated gravity models,Phys

    D.L. Wiltshire,Black holes in string-generated gravity models,Phys. Rev. D38 (1988) 2445. – 18 –

  5. [5]

    Fradkin and A.A

    E.S. Fradkin and A.A. Tseytlin,Nonlinear Electrodynamics from Quantized Strings, Phys. Lett. B163(1985) 123

  6. [6]

    Leigh,Dirac-Born-Infeld action from dirichlet sigma model,Mod

    R.G. Leigh,Dirac-Born-Infeld action from dirichlet sigma model,Mod. Phys. Lett. A 04(1989) 2767

  7. [7]

    Holographic superconductors in the Born-Infeld electrodynamics

    J. Jing and S. Chen,Holographic superconductors in the Born-Infeld electrodynamics, Phys. Lett. B686(2010) 68 [1001.4227]

  8. [8]

    Born-Infeld Black Holes in (A)dS Spaces

    R.-G. Cai, D.-W. Pang and A. Wang,Born-Infeld black holes in (A)dS spaces,Phys. Rev. D70(2004) 124034 [hep-th/0410158]

  9. [9]

    Bardeen,Non-singular general-relativistic gravitational collapse, inProceedings of GR5, Tbilisi, p

    J.M. Bardeen,Non-singular general-relativistic gravitational collapse, inProceedings of GR5, Tbilisi, p. 174, 1968

  10. [10]

    Regular Black Hole in General Relativity Coupled to Nonlinear Electrodynamics

    E. Ayon-Beato and A. Garcia,Regular black hole in general relativity coupled to nonlinear electrodynamics,Phys. Rev. Lett.80(1998) 5056 [gr-qc/9911046]

  11. [11]

    New Regular Black Hole Solution from Nonlinear Electrodynamics

    E. Ayon-Beato and A. Garcia,New regular black hole solution from nonlinear electrodynamics,Phys. Lett. B464(1999) 25 [hep-th/9911174]

  12. [12]

    Regular Magnetic Black Holes and Monopoles from Nonlinear Electrodynamics

    K.A. Bronnikov,Regular magnetic black holes and monopoles from nonlinear electrodynamics,Phys. Rev. D63(2001) 044005 [gr-qc/0006014]

  13. [13]

    Verbin, B

    Y. Verbin, B. Pulice, A. Övgün and H. Huang,New black hole solutions of second and first order formulations of nonlinear electrodynamics,Phys. Rev. D111(2025) 084061 [2412.20989]

  14. [14]

    Building an AdS/CFT superconductor

    S.A. Hartnoll, C.P. Herzog and G.T. Horowitz,Building a Holographic Superconductor,Phys. Rev. Lett.101(2008) 031601 [0803.3295]

  15. [15]

    Enthalpy and the Mechanics of AdS Black Holes

    D. Kastor, S. Ray and J. Traschen,Enthalpy and the mechanics of AdS black holes, Class. Quant. Grav.26(2009) 195011 [0904.2765]

  16. [16]

    Extended phase space thermodynamics for charged and rotating black holes and Born-Infeld vacuum polarization

    S. Gunasekaran, R.B. Mann and D. Kubiznak,Extended phase space thermodynamics for charged and rotating black holes and Born-Infeld vacuum polarization,JHEP11 (2012) 110 [1208.6251]

  17. [17]

    Black hole chemistry: thermodynamics with Lambda

    D. Kubizňák, R.B. Mann and M. Teo,Black hole chemistry: thermodynamics withΛ, Class. Quant. Grav.34(2017) 063001 [1608.06147]

  18. [18]

    Gibbons and K.-i

    G.W. Gibbons and K.-i. Maeda,Black Holes and Membranes in Higher Dimensional Theories with Dilaton Fields,Nucl. Phys. B298(1988) 741

  19. [19]

    Theory of the Nernst effect near quantum phase transitions in condensed matter, and in dyonic black holes

    S.A. Hartnoll, P.K. Kovtun, M. Muller and S. Sachdev,Theory of the Nernst effect near quantum phase transitions in condensed matter, and in dyonic black holes, Phys. Rev. B76(2007) 144502 [0706.3215]

  20. [20]

    Charged Black Hole Solutions in Einstein-Born-Infeld gravity with a Cosmological constant

    S. Fernando and D. Krug,Charged black hole solutions in Einstein-Born-Infeld gravity with a cosmological constant,Gen. Rel. Grav.35(2003) 129 [hep-th/0306120]

  21. [21]

    Black hole solutions in Euler-Heisenberg theory

    H. Yajima and T. Tamaki,Black hole solutions in Euler-Heisenberg theory,Phys. Rev. D63(2001) 064007 [gr-qc/0005016]. – 19 –

  22. [22]

    Nonlinear $\arcsin$-electrodynamics and asymptotic Reissner-Nordstr\"om black holes

    S.I. Kruglov,Nonlinear arcsin-electrodynamics and asymptotic Reissner-Nordström black holes,Annalen Phys.528(2016) 588 [1607.07726]

  23. [23]

    Asymptotic Reissner-Nordstrom black holes

    S.H. Hendi,Asymptotic Reissner-Nordstroem black holes,Annals Phys.333(2013) 282 [1405.5359]

  24. [24]

    Croney, R

    L. Croney, R. Gregory and C.J. Ramírez-Valdez,Thermodynamics of dyonic black holes in non-linear electrodynamics,JHEP10(2025) 013 [2506.06437]

  25. [25]

    Wang, Y.-P

    C.-H. Wang, Y.-P. Zhang, T. Zhu and S.-W. Wei,A new type of multi-branch periodic orbits in dyonic black holes,2508.20558

  26. [26]

    Boillat,Nonlinear electrodynamics - Lagrangians and equations of motion,J

    G. Boillat,Nonlinear electrodynamics - Lagrangians and equations of motion,J. Math. Phys.11(1970) 941

  27. [27]

    Geometrical aspects of light propagation in nonlinear electrodynamics

    M. Novello, V.A. De Lorenci, J.M. Salim and R. Klippert,Geometrical aspects of light propagation in nonlinear electrodynamics,Phys. Rev. D61(2000) 045001 [gr-qc/9911085]

  28. [28]

    Light propagation in non linear electrodynamics

    V.A. De Lorenci, R. Klippert, M. Novello and J.M. Salim,Light propagation in nonlinear electrodynamics,Phys. Lett. B482(2000) 134 [gr-qc/0005049]

  29. [29]

    A classification of the effective metric in nonlinear electrodynamics

    E. Goulart de Oliveira Costa and S. Esteban Perez Bergliaffa,A Classification of the effective metric in nonlinear electrodynamics,Class. Quant. Grav.26(2009) 135015 [0905.3673]

  30. [30]

    Fresnel analysis of the wave propagation in nonlinear electrodynamics

    Y.N. Obukhov and G.F. Rubilar,Fresnel analysis of the wave propagation in nonlinear electrodynamics,Phys. Rev. D66(2002) 024042 [gr-qc/0204028]

  31. [31]

    Övgün and R.C

    A. Övgün and R.C. Pantig,Finite Distance Corrections to Vacuum Birefringence in Strong Gravitational and Electromagnetic Fields,2512.18727

  32. [32]

    Marks, S.J

    G.A. Marks, S.J. Staelens, T. Evstafyeva and U. Sperhake,Long-Term Stable Nonlinear Evolutions of Ultracompact Black-Hole Mimickers,Phys. Rev. Lett.135 (2025) 131402 [2504.17775]

  33. [33]

    Fonseca, C.F.B

    D.S. Fonseca, C.F.B. Macedo, M.M. Corrêa and D. Rubiera-Garcia,Matter environments around black holes: geodesics, light rings and ultracompact configurations,2512.22267

  34. [34]

    Murk and I

    S. Murk and I. Soranidis,Light rings and causality for nonsingular ultracompact objects sourced by nonlinear electrodynamics,Phys. Rev. D110(2024) 044064 [2406.07957]

  35. [35]

    de Paula, H.C.D

    M.A.A. de Paula, H.C.D. Lima Junior, P.V.P. Cunha and L.C.B. Crispino, Electrically charged regular black holes in nonlinear electrodynamics: Light rings, shadows, and gravitational lensing,Phys. Rev. D108(2023) 084029 [2305.04776]

  36. [36]

    J. Tang, Y. Liu, W.-L. Qian and R. Yue,Effect of nonlinear electrodynamics on shadows of slowly rotating black holes,Chin. Phys. C47(2023) 025105

  37. [37]

    S. Yuan, C. Luo, C. Luo, Z. Hu, Z. Zhang and B. Chen,QED effects on Kerr-Newman black hole shadows,Chin. Phys. C49(2025) 025103 [2403.06886]. – 20 –

  38. [38]

    Alloqulov, A

    M. Alloqulov, A. Abdujabbarov, B. Ahmedov and C. Yuan,Probing the gravity of a Schwarzschild black hole in the presence of a cloud of strings with EMRIs, 2512.12672

  39. [39]

    Fathi, A

    M. Fathi, A. Guzmán and J.R. Villanueva,Quasinormal modes of a static black hole in nonlinear electrodynamics,2512.02714

  40. [40]

    Quasinormal modes of black holes and black branes

    E. Berti, V. Cardoso and A.O. Starinets,Quasinormal modes of black holes and black branes,Class. Quant. Grav.26(2009) 163001 [0905.2975]

  41. [41]

    Overdamped modes in Schwarzschild-de Sitter and a Mathematica package for the numerical computation of quasinormal modes

    A. Jansen,Overdamped modes in Schwarzschild-de Sitter and a Mathematica package for the numerical computation of quasinormal modes,Eur. Phys. J. Plus132(2017) 546 [1709.09178]

  42. [42]

    Quasinormal modes of black holes: from astrophysics to string theory

    R.A. Konoplya and A. Zhidenko,Quasinormal modes of black holes: From astrophysics to string theory,Rev. Mod. Phys.83(2011) 793 [1102.4014]

  43. [43]

    Bolokhov and M

    S.V. Bolokhov and M. Skvortsova,Review of analytic results on quasinormal modes of black holes,2504.05014

  44. [44]

    Nomura and D

    K. Nomura and D. Yoshida,Quasinormal modes of charged black holes with corrections from nonlinear electrodynamics,Phys. Rev. D105(2022) 044006 [2111.06273]

  45. [45]

    Pantig, L

    R.C. Pantig, L. Mastrototaro, G. Lambiase and A. Övgün,Shadow, lensing, quasinormal modes, greybody bounds and neutrino propagation by dyonic ModMax black holes,Eur. Phys. J. C82(2022) 1155 [2208.06664]

  46. [46]

    Aliyan and K

    F. Aliyan and K. Nozari,Shadow behavior of an EMSG charged black hole,Phys. Dark Univ.46(2024) 101611 [2408.08289]

  47. [47]

    Zare, L.M

    S. Zare, L.M. Nieto, X.-H. Feng, S.-H. Dong and H. Hassanabadi,Shadows, rings and optical appearance of a magnetically charged regular black hole illuminated by various accretion disks,JCAP08(2024) 041 [2406.07300]

  48. [48]

    Causality and energy conditions in nonlinear electrodynamics,

    J.G. Russo and P.K. Townsend,Causality and energy conditions in nonlinear electrodynamics,JHEP06(2024) 191 [2404.09994]

  49. [49]

    Boyd,Chebyshev and Fourier Spectral Methods, Dover Publications, Mineola, New York, 2nd ed

    J.P. Boyd,Chebyshev and Fourier Spectral Methods, Dover Publications, Mineola, New York, 2nd ed. (2001)

  50. [50]

    Light rings as observational evidence for event horizons: long-lived modes, ergoregions and nonlinear instabilities of ultracompact objects

    V. Cardoso, L.C.B. Crispino, C.F.B. Macedo, H. Okawa and P. Pani,Light rings as observational evidence for event horizons: long-lived modes, ergoregions and nonlinear instabilities of ultracompact objects,Phys. Rev. D90(2014) 044069 [1406.5510]

  51. [51]

    Light ring stability in ultra-compact objects

    P.V.P. Cunha, E. Berti and C.A.R. Herdeiro,Light-Ring Stability for Ultracompact Objects,Phys. Rev. Lett.119(2017) 251102 [1708.04211]

  52. [52]

    Cunha,Backreaction of perturbations around a stable Light Ring,2503.00117

    P.V.P. Cunha,Backreaction of perturbations around a stable Light Ring,2503.00117

  53. [53]

    Israel,Singular hypersurfaces and thin shells in general relativity,Nuovo Cim

    W. Israel,Singular hypersurfaces and thin shells in general relativity,Nuovo Cim. B 44S10(1966) 1. – 21 –

  54. [54]

    Vlachos, E

    C. Vlachos, E. Papantonopoulos and K. Destounis,Echoes of Compact Objects in Scalar-Tensor Theories of Gravity,Phys. Rev. D103(2021) 044042 [2101.12196]

  55. [55]

    Dong and D

    R. Dong and D. Stojkovic,Gravitational wave echoes from black holes in massive gravity,Phys. Rev. D103(2021) 024058 [2011.04032]

  56. [56]

    Echoes of ECOs: gravitational-wave signatures of exotic compact objects and of quantum corrections at the horizon scale

    V. Cardoso, S. Hopper, C.F.B. Macedo, C. Palenzuela and P. Pani, Gravitational-wave signatures of exotic compact objects and of quantum corrections at the horizon scale,Phys. Rev. D94(2016) 084031 [1608.08637]

  57. [57]

    Echoes of Kerr-like wormholes

    P. Bueno, P.A. Cano, F. Goelen, T. Hertog and B. Vercnocke,Echoes of Kerr-like wormholes,Phys. Rev. D97(2018) 024040 [1711.00391]

  58. [58]

    Churilova, R.A

    M.S. Churilova, R.A. Konoplya, Z. Stuchlik and A. Zhidenko,Wormholes without exotic matter: quasinormal modes, echoes and shadows,JCAP10(2021) 010 [2107.05977]

  59. [59]

    Konoplya and A

    R.A. Konoplya and A. Zhidenko,Primary hairs may create echoes,Phys. Lett. B 872(2026) 140108

  60. [60]

    About the Significance of Quasinormal Modes of Black Holes

    H.-P. Nollert,About the significance of quasinormal modes of black holes,Phys. Rev. D53(1996) 4397 [gr-qc/9602032]

  61. [61]

    Pseudospectrum and black hole quasi-normal mode (in)stability

    J.L. Jaramillo, R. Panosso Macedo and L. Al Sheikh,Pseudospectrum and Black Hole Quasinormal Mode Instability,Phys. Rev. X11(2021) 031003 [2004.06434]

  62. [62]

    Destabilizing the Fundamental Mode of Black Holes: The Elephant and the Flea,

    M.H.-Y. Cheung, K. Destounis, R.P. Macedo, E. Berti and V. Cardoso,Destabilizing the Fundamental Mode of Black Holes: The Elephant and the Flea,Phys. Rev. Lett. 128(2022) 111103 [2111.05415]

  63. [63]

    Berti, V

    E. Berti, V. Cardoso, M.H.-Y. Cheung, F. Di Filippo, F. Duque, P. Martens et al., Stability of the fundamental quasinormal mode in time-domain observations against small perturbations,Phys. Rev. D106(2022) 084011 [2205.08547]. – 22 –