Fractal signatures of non-Kerr spacetimes in the shadow of light-ring bifurcations

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Kostaros, Konstantinos, Papadopoulos, Padelis, Pappas, George
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866913417106817024
author Kostaros, Konstantinos
Papadopoulos, Padelis
Pappas, George
author_facet Kostaros, Konstantinos
Papadopoulos, Padelis
Pappas, George
contents Light-ring bifurcations that can occur for prolate non-Kerr compact objects can leave an indelible signature on SMBH shadows as a fractal sequence of eyebrow-like formations. These fractal features are the result of two properties of these spacetimes. The first is that they allow for multiple escapes for the photons (throats in the effective potential of photon geodesic motion). The second is that photon geodesics can resonate between different generalized light-rings related to the escapes, called fundamental photon orbits, that lead photons to alternate between the different exits either towards the compact object or infinity. The resulting fractal structures of the shadow seem to be a generic feature of prolate non-Kerr objects that may be observable in (accretion-disk)-illuminated compact objects, especially along equatorial lines of sight, but the best orientation depends on the specific parameters. Such fractal features if observed in the shadows of singular supermassive black holes at the centers of galaxies, would be smoking gun signals of non-Kerr compact objects.
format Preprint
id arxiv_https___arxiv_org_abs_2405_09653
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Fractal signatures of non-Kerr spacetimes in the shadow of light-ring bifurcations
Kostaros, Konstantinos
Papadopoulos, Padelis
Pappas, George
General Relativity and Quantum Cosmology
Light-ring bifurcations that can occur for prolate non-Kerr compact objects can leave an indelible signature on SMBH shadows as a fractal sequence of eyebrow-like formations. These fractal features are the result of two properties of these spacetimes. The first is that they allow for multiple escapes for the photons (throats in the effective potential of photon geodesic motion). The second is that photon geodesics can resonate between different generalized light-rings related to the escapes, called fundamental photon orbits, that lead photons to alternate between the different exits either towards the compact object or infinity. The resulting fractal structures of the shadow seem to be a generic feature of prolate non-Kerr objects that may be observable in (accretion-disk)-illuminated compact objects, especially along equatorial lines of sight, but the best orientation depends on the specific parameters. Such fractal features if observed in the shadows of singular supermassive black holes at the centers of galaxies, would be smoking gun signals of non-Kerr compact objects.
title Fractal signatures of non-Kerr spacetimes in the shadow of light-ring bifurcations
topic General Relativity and Quantum Cosmology
url https://arxiv.org/abs/2405.09653