Zobrazeno 1 - 10
of 156
pro vyhledávání: '"Eleftherios Papantonopoulos"'
Autor:
Dionysios P. Theodosopoulos, Thanasis Karakasis, George Koutsoumbas, Eleftherios Papantonopoulos
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 84, Iss 6, Pp 1-36 (2024)
Abstract We study the motion of uncharged particles and photons in the background of a magnetically charged Euler–Heisenberg (EH) black hole (BH) with scalar hair. The spacetime can be asymptotically (A)dS or flat. After investigating particle moti
Externí odkaz:
https://doaj.org/article/8bbcd68e4c0247a7a0b68dd0813116a5
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 84, Iss 3, Pp 1-19 (2024)
Abstract We consider scalar field perturbations in the background of black holes immersed in perfect fluid dark matter (PFDM). We find, by using the sixth-order Wentzel–Kramers–Brillouin (WKB) approximation, that the longest-lived modes are those
Externí odkaz:
https://doaj.org/article/d338a8918ebd44feaa47c07cd944436a
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 83, Iss 1, Pp 1-12 (2023)
Abstract In the framework of the dynamical Chern–Simons gravity, we study the scalar field perturbations of the Reissner–Nordström–Melvin spacetime, which describes a charged black hole permeated by a uniform magnetic field. In the presence of
Externí odkaz:
https://doaj.org/article/1c413355b37d4c16bf938d61705c3019
Publikováno v:
Journal of High Energy Physics, Vol 2022, Iss 6, Pp 1-35 (2022)
Abstract The anomalous decay rate of the quasinormal modes occurs when the longest-lived modes are the ones with higher angular number. Such behaviour has been recently studied in different static spacetimes, for uncharged scalar and fermionic pertur
Externí odkaz:
https://doaj.org/article/555b60eff643414f96ac6a4c1fa6c6c6
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 10, Pp 1-14 (2021)
Abstract We report exact black hole solutions in asymptotically flat or (A)dS four-dimensional spacetime with a conformally coupled self-interacting scalar field in f(R) gravity. We first consider the asymptotically flat model $$f(R) = R -2\alpha \sq
Externí odkaz:
https://doaj.org/article/825d598101e3457298872bbf5c3577d1
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 9, Pp 1-13 (2021)
Abstract Black hole spontaneous scalarization has been attracting more and more attention as it circumvents the well-known no-hair theorems. In this work, we study the scalarization in Einstein–scalar-Gauss–Bonnet theory with a probe scalar field
Externí odkaz:
https://doaj.org/article/58a7902e7cdc45dc9a77f3afe7f30479
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 5, Pp 1-16 (2021)
Abstract We study the propagation of scalar fields in the background of an asymptotically de Sitter black hole solution in f(R) gravity. The aim of this work is to analyze in modified theories of gravity the existence of an anomalous decay rate of th
Externí odkaz:
https://doaj.org/article/3cba571f10de41cc95ab68c7cbaeaed2
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 4, Pp 1-16 (2021)
Abstract We consider Maxwell-f(R) gravity and obtain an exact charged black hole solution with dynamic curvature in D-dimensions. Considering a spherically symmetric metric ansatz and without specifying the form of f(R) we find a general black hole s
Externí odkaz:
https://doaj.org/article/9ff97692f812455f8e8d9045cf5d58b9
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 80, Iss 10, Pp 1-12 (2020)
Abstract We study the motion of particles in the background of a scalar–tensor theory of gravity in which the scalar field is kinetically coupled to the Einstein tensor. We constrain the value of the derivative parameter z through solar system test
Externí odkaz:
https://doaj.org/article/11174a3fdad74a20a673973b1f083e1f
Publikováno v:
Journal of High Energy Physics, Vol 2020, Iss 8, Pp 1-27 (2020)
Abstract Recently an anomalous decay rate of the quasinormal modes of a massive scalar field in Schwarzschild black holes backgrounds was reported in which the longest-lived modes are the ones with higher angular number, for a scalar field mass small
Externí odkaz:
https://doaj.org/article/052caa5a531d4c5c96b1f90dae8af6e7