Zobrazeno 1 - 10
of 13 983
pro vyhledávání: '"Júnior, José"'
This paper presents a systematic exploration of exact solutions for electrically charged wormholes, black holes, and black bounces within the hybrid metric-Palatini gravity (HMPG) framework. HMPG combines features of the metric and Palatini formulati
Externí odkaz:
http://arxiv.org/abs/2412.10324
This paper investigates the lack of research on activation functions for neural network models in time series tasks. It highlights the need to identify essential properties of these activations to improve their effectiveness in specific domains. To t
Externí odkaz:
http://arxiv.org/abs/2412.09889
Autor:
Junior, Ednaldo L. B., Junior, José Tarciso S. S., Lobo, Francisco S. N., Rodrigues, Manuel E., Rubiera-Garcia, Diego, da Silva, Luís F. Dias, Vieira, Henrique A.
In this paper, we study time-like geodesics around a spherically symmetric black hole in Kalb-Ramond (KR) gravity, characterized by the parameter $l$, which induces spontaneous Lorentz symmetry breaking. The geodesic equations and effective potential
Externí odkaz:
http://arxiv.org/abs/2412.00769
Autor:
Róis, Gabriel I., Junior, José Tarciso S. S., Lobo, Francisco S. N., Rodrigues, Manuel E., Harko, Tiberiu
In this work, we investigate static and spherically symmetric black hole solutions in $f(R,T)$ gravity, where $R$ is the curvature scalar and $T$ is the trace of the energy-momentum tensor, coupled to nonlinear electrodynamics (NLED). To construct ou
Externí odkaz:
http://arxiv.org/abs/2412.00582
Autor:
Junior, Ednaldo L. B., Junior, José Tarciso S. S., Lobo, Francisco S. N., Rodrigues, Manuel E., Rubiera-Garcia, Diego, da Silva, Luís F. Dias, Vieira, Henrique A.
We consider a recently introduced extension of General Relativity dubbed as Cotton gravity (CG), based on the use of the Cotton tensor, to estimate the size of a new constant $\gamma$ appearing within a spherically symmetric, vacuum solution of the t
Externí odkaz:
http://arxiv.org/abs/2407.21655
Autor:
Junior, Ednaldo L. B., Junior, José Tarciso S. S., Lobo, Francisco S. N., Rodrigues, Manuel E., Rubiera-Garcia, Diego, da Silva, Luís F. Dias, Vieira, Henrique A.
Publikováno v:
Eur. Phys. J. C 84, 1190 (2024)
Recently, J. Harada proposed a theory relating gravity to the Cotton tensor, dubbed as ''Cotton gravity'' (CG). This is an extension of General Relativity such that every solution of the latter turns out to be a solution of the former (but the conver
Externí odkaz:
http://arxiv.org/abs/2407.21649
Autor:
de Lima Nunes, Fabiano, Júnior, José Antônio Valle Antunes, Dupont, André, Pires, Gabriel, Sordi, Jefferson Dobner, de Quevedo, Daniela Müller
Publikováno v:
South African Journal of Industrial Engineering, Vol 31, Iss 1, Pp 93-109 (2020)
This research aimed at identifying the competitive criteria that, together with modularisation, impacted the differentiation strategy in industries manufacturing machinery and equipment in Brazil. This was survey-type research that used structural eq
Externí odkaz:
https://doaj.org/article/4771b6670e2c42618721a802f9e4607c
Publikováno v:
Eur. Phys. J. C 84, 557 (2024)
In this work, we analyse black bounce solutions in the recently proposed ``Conformal Killing gravity'' (CKG), by coupling the theory to nonlinear electrodynamics (NLED) and scalar fields. The original motivation of the theory was essentially to fulfi
Externí odkaz:
http://arxiv.org/abs/2405.09702
Autor:
Junior, Ednaldo L. B., Junior, José Tarciso S. S., Lobo, Francisco S. N., Rodrigues, Manuel E., Rubiera-Garcia, Diego, da Silva, Luís F. Dias, Vieira, Henrique A.
Publikováno v:
Eur. Phys. J. C 84, 1257 (2024)
In this work, we study timelike and lightlike geodesics in Kalb-Ramond (KR) gravity around a black hole with the goal of constraining the Lorentz symmetry-breaking parameter $l$. The analysis involves studying the precession of the S2 star periastron
Externí odkaz:
http://arxiv.org/abs/2405.03291
Autor:
Junior, Ednaldo L. B., Junior, José Tarciso S. S., Lobo, Francisco S. N., Rodrigues, Manuel E., Rubiera-Garcia, Diego, da Silva, Luís F. Dias, Vieira, Henrique A.
Publikováno v:
Phys. Rev. D 110, 024077 (2024)
In this paper, we investigate the gravitational lensing effect for the Schwarzschild-like black hole spacetime in the background of a Kalb-Ramond (KR) field proposed in [K. Yang et. al., Phys. Rev. D 108 (2023) 124004]. The solution is characterized
Externí odkaz:
http://arxiv.org/abs/2405.03284