Analytical approach for calculating shadow of dynamical black hole

Autor:	Vertogradov, Vitalii, Övgün, Ali
Rok vydání:	2024
Předmět:	General Relativity and Quantum Cosmology
Druh dokumentu:	Working Paper
Popis:	A real astrophysical black hole, surrounded by an accretion disc, experiences time-dependent mass variation due to accretion, impacting observable features like the shadow. In this work, we analyzed the dynamical shadow by extending the concept of the photon sphere to time-dependent spacetimes, incorporating induced, centrifugal, and relativistic forces. We demonstrated that the shadow grows when light loses energy and shrinks when it gains energy, with a surprising result that the shadow remains static when the photon sphere radius coincides with the NEC horizon radius. Our method, assuming a small accretion rate, provides a foundation for studying dynamical black holes, offering insights into processes like gravitational collapse, which could make shadow evolution detectable and reveal details about black hole formation. Comment: 9 pages
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2412.10930 Zobrazit plný text záznamu View this record from Arxiv