Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 4.0 International license. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

Export citation

Export citation

Choose format for download:

Download Citation
  • Open Access

Interferometric signature of higher-order images in a parametrized framework

Fabiano Feleppa1,2,3,*, Fabio Aratore1,2,†, and Valerio Bozza1,2,‡

  • *Contact author: ffeleppa@unisa.it
  • †Contact author: faratore@unisa.it
  • ‡Contact author: vbozza@unisa.it

Phys. Rev. D 112, 044007 – Published 5 August, 2025

DOI: https://doi.org/10.1103/1gls-k3df

Abstract

This paper investigates gravitational lensing in the strong deflection limit, focusing particularly on higher-order images produced near compact objects such as black holes and their observable impact through the visibility function. Employing a robust parametrization framework proposed by Rezzolla and Zhidenko, the study systematically explores deviations from the Schwarzschild metric. A detailed theoretical analysis of interferometric observables is provided, highlighting how higher-order images imprint distinctive, measurable patterns in the visibility function, notably characterized by a staircaselike structure. By parametrically varying metric coefficients, the analysis reveals clear dependencies between spacetime deviations and key observational signatures, specifically the step heights and periodicities in the interferometric visibility. The results enhance the theoretical groundwork for interpreting data from advanced interferometric observations, potentially enabling precise tests of general relativity and the discrimination among alternative gravitational theories.

View figure in article

Physics Subject Headings (PhySH)

Article Text

References (94)

  1. S. Weinberg, Gravitation and Cosmology: Principles and Applications of the General Theory of Relativity (John Wiley and Sons, New York, 1972).
  2. C. W. Misner, K. S. Thorne, and J. A. Wheeler, Gravitation (W. H. Freeman, San Francisco, 1973).
  3. P. Schneider, J. Ehlers, and E. Falco, Gravitational Lenses (Springer-Verlag, Berlin Heidelberg, 1992).
  4. R. Narayan and M. Bartelmann, Lectures on gravitational lensing, arXiv:astro-ph/9606001v2.
  5. J. Wambsganss, Gravitational lensing in astronomy, Living Rev. Relativity 1, 12 (1998).
  6. M. Bartelmann and P. Schneider, Weak gravitational lensing, Phys. Rep. 340, 291 (2001).
  7. S. Dodelson, Gravitational Lensing (Cambridge University Press, Cambridge, England, 2017).
  8. M. Meneghetti, Introduction to Gravitational Lensing (Springer International Publishing, New York, 2021).
  9. D. Walsh, R. F. Carswell, and R. J. Weymann, 0957+561 A, B: Twin quasistellar objects or gravitational lens?, Nature (London) 279, 381 (1979).
  10. G. Soucail, Y. Mellier, B. Fort, and J. P. Picat, A blue ring-like structure in the center of the A 370 cluster of galaxies, Astron. Astrophys. 172, L14 (1987).
  11. V. Bozza, S. Capozziello, G. Iovane, and G. Scarpetta, Strong field limit of black hole gravitational lensing, Gen. Relativ. Gravit. 33, 1535 (2001).
  12. C. Darwin, The gravity field of a particle, Proc. R. Soc. A 249, 180 (1959).
  13. R. d’E. Atkinson, On light tracks near a very massive star, Astron. J. 70, 517 (1965).
  14. J.-P. Luminet, Image of a spherical black hole with thin accretion disk, Astron. Astrophys. 75, 228 (1979).
  15. H. C. Ohanian, The black hole as a gravitational “lens”, Am. J. Phys. 55, 428 (1987).
  16. V. Bozza, Gravitational lensing in the strong field limit, Phys. Rev. D 66, 103001 (2002).
  17. V. Bozza, Quasiequatorial gravitational lensing by spinning black holes in the strong field limit, Phys. Rev. D 67, 103006 (2003).
  18. K. S. Virbhadra and G. F. R. Ellis, Schwarzschild black hole lensing, Phys. Rev. D 62, 084003 (2000).
  19. S. Frittelli, T. P. Kling, and E. T. Newman, Spacetime perspective of Schwarzschild lensing, Phys. Rev. D 61, 064021 (2000).
  20. V. Perlick, Exact gravitational lens equation in spherically symmetric and static spacetimes, Phys. Rev. D 69, 064017 (2004).
  21. C.-M. Claudel, K. S. Virbhadra, and G. F. R. Ellis, The geometry of photon surfaces, J. Math. Phys. (N.Y.) 42, 818 (2001).
  22. W. Hasse and V. Perlick, Gravitational lensing in spherically symmetric static spacetimes with centrifugal force reversal, Gen. Relativ. Gravit. 34, 415 (2002).
  23. V. Perlick, Gravitational lensing from a spacetime perspective, Living Rev. Relativity 7, 9 (2004).
  24. S. V. Iyer and A. O. Petters, Light’s bending angle due to black holes: From the photon sphere to infinity, Gen. Relativ. Gravit. 39, 1563 (2007).
  25. K. S. Virbhadra and C. R. Keeton, Time delay and magnification centroid due to gravitational lensing by black holes and naked singularities, Phys. Rev. D 77, 124014 (2008).
  26. G. S. Bisnovatyi-Kogan and O. Yu. Tsupko, Strong gravitational lensing by Schwarzschild black holes, Astrophysics (Engl. Transl.) 51, 99 (2008).
  27. N. Mukherjee and A. S. Majumdar, Rotating brane-world black hole lensing in the strong deflection limit, Gravitation Cosmol. 15, 263 (2009).
  28. A. Tarasenko, Reconstruction of a compact object motion in the vicinity of a black hole by its electromagnetic radiation, Phys. Rev. D 81, 123005 (2010).
  29. E. F. Eiroa and C. M. Sendra, Gravitational lensing by a regular black hole, Classical Quantum Gravity 28, 085008 (2011).
  30. S.-W. Wei, Yu.-X. Liu, C.-E. Fu, and K. Yang, Strong field limit analysis of gravitational lensing in Kerr-Taub-NUT spacetime, J. Cosmol. Astropart. Phys. 10 (2012) 053.
  31. G. Li, Y. Zhang, L. Zhang, Z. Feng, and X. Zu, Strong gravitational lensing in the Einstein-Proca theory, Int. J. Theor. Phys. 54, 1245 (2015).
  32. A. Alhamzawi and R. Alhamzawi, Gravitational lensing in the strong field limit by modified gravity, Gen. Relativ. Gravit. 48, 167 (2016).
  33. N. Tsukamoto, Strong deflection limit analysis and gravitational lensing of an Ellis wormhole, Phys. Rev. D 94, 124001 (2016).
  34. G. F. Aldi and V. Bozza, Relativistic iron lines in accretion disks: The contribution of higher order images in the strong deflection limit, J. Cosmol. Astropart. Phys. 02 (2017) 033.
  35. D.-C. Dai, D. Stojkovic, and G. D. Starkman, Strong lensing constraints on modified gravity models, Phys. Rev. D 98, 124027 (2018).
  36. X.-M. Kuang, Z.-Y. Tang, B. Wang, and A. Wang, Constraining a modified gravity theory in strong gravitational lensing and black hole shadow observations, Phys. Rev. D 106, 064012 (2022).
  37. F. Aratore and V. Bozza, Analytical perturbations of relativistic images in Kerr space-time, J. Cosmol. Astropart. Phys. 07 (2024) 033.
  38. M.-Y. Guo, M.-H. Wu, H. Guo, X.-M. Kuang, and F.-Y. Liu, Strong gravitational lensing effects around rotating regular black holes, Phys. Lett. B 860, 139211 (2025).
  39. S. E. Gralla, D. E. Holz, and R. M. Wald, Black hole shadows, photon rings, and lensing rings, Phys. Rev. D 100, 024018 (2019).
  40. M. D. Johnson, A. Lupsasca, A. Strominger, G. N. Wong, S. Hadar, D. Kapec, R. Narayan, A. Chael, C. F. Gammie, P. Galison et al., Universal interferometric signatures of a black hole’s photon ring, Sci. Adv. 6, 12 (2020).
  41. S. E. Gralla and A. Lupsasca, Observable shape of black hole photon rings, Phys. Rev. D 102, 124003 (2020).
  42. S. E. Gralla, A. Lupsasca, and D. P. Marrone, The shape of the black hole photon ring: A precise test of strong- field general relativity, Phys. Rev. D 102, 124004 (2020).
  43. S. E. Gralla and A. Lupsasca, Lensing by Kerr black holes, Phys. Rev. D 101, 044031 (2020).
  44. M. Wielgus, Photon rings of spherically symmetric black holes and robust tests of non-Kerr metrics, Phys. Rev. D 104, 124058 (2021).
  45. A. E. Broderick, P. Tiede, D. W. Pesce, and R. Gold, Measuring spin from relative photon ring sizes, Astrophys. J. 927, 6 (2022).
  46. D. Ayzenberg, Testing gravity with black hole shadow subrings, Classical Quantum Gravity 39, 105009 (2022).
  47. M. Guerrero, G. J. Olmo, D. Rubiera-Garcia, and D. S.-C. Gómez, Multiring images of thin accretion disk of a regular naked compact object, Phys. Rev. D 106, 044070 (2022).
  48. G. S. Bisnovatyi-Kogan and O. Y. Tsupko, Analytical study of higher-order ring images of the accretion disk around a black hole, Phys. Rev. D 105, 064040 (2022).
  49. O. Yu. Tsupko, Shape of higher-order images of equatorial emission rings around a Schwarzschild black hole: Analytical description with polar curves, Phys. Rev. D 106, 064033 (2022).
  50. A. Eichhorn, A. Held, and P.-V. Johannsen, Universal signatures of singularity-resolving physics in photon rings of black holes and horizonless objects, J. Cosmol. Astropart. Phys. 01 (2023) 043.
  51. A. E. Broderick, K. Salehi, and B. Georgiev, Shadow implications: What does measuring the photon ring imply for gravity?, Astrophys. J. 958, 114 (2023).
  52. P. Kocherlakota, L. Rezzolla, R. Roy, and M. Wielgus, Hotspots and photon rings in Schwarzschild black hole spacetimes, Mon. Not. R. Astron. Soc. 531, 3606 (2024).
  53. F. Aratore, O. Yu. Tsupko, and V. Perlick, Constraining spherically symmetric metrics by the gap between photon rings, Phys. Rev. D 109, 124057 (2024).
  54. O. Yu. Tsupko and G. S. Bisnovatyi-Kogan, Gravitational lensing in plasma: Relativistic images at homogeneous plasma, Phys. Rev. D 87, 124009 (2013).
  55. F. Feleppa, V. Bozza, and O. Yu. Tsupko, Strong deflection limit analysis of black hole lensing in inhomogeneous plasma, Phys. Rev. D 110, 064031 (2024).
  56. F. Feleppa, V. Bozza, and O. Yu. Tsupko, Strong deflection of massive particles in spherically symmetric spacetimes, Phys. Rev. D 111, 044018 (2024).
  57. K. Akiyama, A. Alberdi, W. Alef, K. Asada, R. Azulay, A.-K. Baczko, D. Ball et al. (Event Horizon Telescope Collaboration), First M87 Event Horizon Telescope results. I. The shadow of the supermassive black hole, Astrophys. J. Lett. 875, L1 (2019).
  58. K. Akiyama, A. Alberdi, W. Alef, K. Asada, R. Azulay, A.-K. Baczko, D. Ball et al. (Event Horizon Telescope Collaboration), First M87 Event Horizon Telescope results. II. Array and instrumentation, Astrophys. J. Lett. 875, L2 (2019).
  59. K. Akiyama, A. Alberdi, W. Alef, K. Asada, R. Azulay, A.-K. Baczko, D. Ball et al. (Event Horizon Telescope Collaboration), First M87 Event Horizon Telescope results. III. Data processing and calibration, Astrophys. J. Lett. 875, L3 (2019).
  60. K. Akiyama, A. Alberdi, W. Alef, K. Asada, R. Azulay, A.-K. Baczko, D. Ball et al. (Event Horizon Telescope Collaboration), First M87 Event Horizon Telescope results. IV. Imaging the central supermassive black hole, Astrophys. J. Lett. 875, L4 (2019).
  61. K. Akiyama, A. Alberdi, W. Alef, K. Asada, R. Azulay, A.-K. Baczko, D. Ball et al. (Event Horizon Telescope Collaboration), First M87 Event Horizon Telescope results. V. Physical origin of the asymmetric ring, Astrophys. J. Lett. 875, L5 (2019).
  62. K. Akiyama, A. Alberdi, W. Alef, K. Asada, R. Azulay, A.-K. Baczko, D. Ball et al. (Event Horizon Telescope Collaboration), First M87 Event Horizon Telescope results. VI. The shadow and mass of the central black hole, Astrophys. J. Lett. 875, L6 (2019).
  63. K. Akiyama, A. Alberdi, W. Alef, J. C. Algaba, R. Anantua, K. Asada, R. Azulay, U. Bach, A.-K. Baczko, D. Ball et al. (Event Horizon Telescope Collaboration), First Sagittarius A* Event Horizon Telescope results. I. The shadow of the supermassive black hole in the center of the Milky Way, Astrophys. J. Lett. 930, L12 (2022).
  64. K. Akiyama, A. Alberdi, W. Alef, J. C. Algaba, R. Anantua, K. Asada, R. Azulay et al. (Event Horizon Telescope Collaboration), First Sagittarius A* Event Horizon Telescope results. II. EHT and multiwavelength observations, data processing, and calibration, Astrophys. J. Lett. 930, L13 (2022).
  65. K. Akiyama, A. Alberdi, W. Alef, J. C. Algaba, R. Anantua, K. Asada, R. Azulay et al. (Event Horizon Telescope Collaboration), First Sagittarius A* Event Horizon Telescope results. III. Imaging of the Galactic center supermassive black hole, Astrophys. J. Lett. 930, L14 (2022).
  66. K. Akiyama, A. Alberdi, W. Alef, J. C. Algaba, R. Anantua, K. Asada et al. (Event Horizon Telescope Collaboration), First Sagittarius A* Event Horizon Telescope results. IV. Variability, morphology, and black hole mass, Astrophys. J. Lett. 930, L15 (2022).
  67. K. Akiyama, A. Alberdi, W. Alef, J. C. Algaba, R. Anantua, K. Asada, R. Azulay et al. (Event Horizon Telescope Collaboration), First Sagittarius A* Event Horizon Telescope results. V. Testing astrophysical models of the Galactic center black hole, Astrophys. J. Lett. 930, L16 (2022).
  68. K. Akiyama, A. Alberdi, W. Alef, J. C. Algaba, R. Anantua, K. Asada, R. Azulay et al. (Event Horizon Telescope Collaboration), First Sagittarius A* Event Horizon Telescope results. VI. Testing the black hole metric, Astrophys. J. Lett. 930, L17 (2022).
  69. K. Akiyama, A. Alberdi, W. Alef, J. C. Algaba, R. Anantua, K. Asada, R. Azulay et al. (Event Horizon Telescope Collaboration), First M87 Event Horizon Telescope results. VII. Polarization of the ring, Astrophys. J. Lett. 910, L12 (2021).
  70. K. Akiyama, A. Alberdi, W. Alef, J. C. Algaba, R. Anantua, K. Asada, R. Azulay et al. (Event Horizon Telescope Collaboration), First M87 Event Horizon Telescope results. VIII. Magnetic field structure near the event horizon, Astrophys. J. Lett. 910, L13 (2021).
  71. F. Tamburini, B. Thidé, and M. Della Valle, Measurement of the spin of the M87 black hole from its observed twisted light, Mon. Not. R. Astron. Soc.: Lett. 492, L22 (2020).
  72. F. Tamburini, F. Feleppa, and B. Thidé, Twisted light, a new tool for general relativity and beyond—Revealing the properties of rotating black holes with the vorticity of light—, Int. J. Mod. Phys. D 30, 2142017 (2021).
  73. F. Tamburini, F. Feleppa, B. Thidé, and I. Licata, Kerr-spacetime geometric optics for vortex beams, Phys. Rev. D 104, 013718 (2021).
  74. F. Aratore and V. Bozza, Decoding a black hole metric from the interferometric pattern of the relativistic images of a compact source, J. Cosmol. Astropart. Phys. 10 (2021) 054.
  75. L. Rezzolla and A. Zhidenko, New parametrization for spherically symmetric black holes in metric theories of gravity, Phys. Rev. D 90, 084009 (2014).
  76. T. Johannsen and D. Psaltis, Metric for rapidly spinning black holes suitable for strong-field tests of the no-hair theorem, Phys. Rev. D 83, 124015 (2011).
  77. V. Cardoso, P. Pani, and J. Rico, On generic parametrizations of spinning black-hole geometries, Phys. Rev. D 89, 064007 (2014).
  78. S. Shaymatov, B. Ahmedov, M. De Laurentis, M. Jamil, Q. Wu, A. Wang, and M. Azreg-Aïnou, On the parameters of the spherically symmetric parameterized Rezzolla–Zhidenko spacetime through solar system tests, the orbit of the s2 star about Sgr A*, and quasiperiodic oscillations, Astrophys. J. 959, 1 (2023).
  79. B. Toshmatov and B. Ahmedov, Tidal forces in parametrized spacetime: Rezzolla-Zhidenko parametrization, Phys. Rev. D 108, 084035 (2023).
  80. M. Alloqulov, H. Chakrabarty, D. Malafarina, B. Ahmedov, and A. Abdujabbarov, Gravitational lensing of neutrinos in parametrized black hole spacetimes, J. Cosmol. Astropart. Phys. 02 (2025) 070.
  81. K. Moriyama, A. Cruz-Osorio, Y. Mizuno, I. K. Dihingia, and A. Uniyal, Black hole accretion and radiation variability in general relativistic magnetohydrodynamic simulations with Rezzolla–Zhidenko spacetime, Astron. Astrophys. 694, A135 (2025).
  82. V. Bozza and G. Scarpetta, Strong deflection limit of black hole gravitational lensing with arbitrary source distances, Phys. Rev. D 76, 083008 (2007).
  83. V. I. Dokuchaev and N. O. Nazarova, Event horizon image within black hole shadow, Sov. J. Exp. Theor. Phys. 128, 578 (2019).
  84. V. I. Dokuchaev and N. O. Nazarova, Visible shapes of black holes M87* and SgrA*, Universe 6, 154 (2020).
  85. V. I. Dokuchaev and N. O. Nazarova, Silhouettes of invisible black holes, Phys. Usp. 63, 583 (2020).
  86. A. Chael, M. D. Johnson, and A. Lupsasca, Observing the inner shadow of a black hole: A direct view of the event horizon, Astrophys. J. 918, 1 (2021).
  87. P. Kocherlakota, L. Rezzolla, R. Roy, and M. Wielgus, Prospects for future experimental tests of gravity with black hole imaging: Spherical symmetry, Phys. Rev. D 109, 064064 (2007).
  88. H. Reissner, Über die Eigengravitation des elektrischen Feldes nach der Einsteinschen Theorie, Ann. Phys. (Berlin) 355, 106 (1916).
  89. G. Nordström, On the energy of the gravitational field in Einstein’s theory, Verhandelingen der Koninklijke Nederlandse Akademie van Wetenschappen, Afdeling Natuurkunde 26, 1201 (1918).
  90. A. García, D. Galtsov, and O. Kechkin, Class of stationary axisymmetric solutions of the Einstein-Maxwell-dilaton-axion field equations, Phys. Rev. Lett. 74, 1276 (1995).
  91. P. Kocherlakota and L. Rezzolla, Accurate mapping of spherically symmetric black holes in a parametrized framework, Phys. Rev. D 102, 064058 (2020).
  92. P. Kocherlakota and L. Rezzolla, Comment on the analytical bounds in the Rezzolla-Zhidenko parametrization, arXiv:2206.03146v1.
  93. R. Konoplya, L. Rezzolla, and A. Zhidenko, General parametrization of axisymmetric black holes in metric theories of gravity, Phys. Rev. D 93, 064015 (2016).
  94. P. Kocherlakota and L. Rezzolla, Distinguishing gravitational and emission physics in black hole imaging: Spherical symmetry, Mon. Not. R. Astron. Soc. 513, 1 (2022).

Outline

Information

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation