16 citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Universidade Federal do ParáBR7 papers
- Universidade Federal do Rio Grande do NorteBR6 papers
- Universidade Federal do CearáBR5 papers
- University of LisbonPT4 papers
- Universidade Federal Rural do Semi-ÁridoBR3 papers
- Centro Brasileiro de Pesquisas FísicasBR2 papers
- European Southern ObservatoryCL2 papers
- Institute of Astrophysics and Space SciencesPT2 papers
- Instituto Federal de Educação, Ciência e Tecnologia do ParáBR2 papers
- Osservatorio Astrofisico di CataniaIT2 papers
- Universidad Complutense de MadridES2 papers
- Universidade Federal da BahiaBR2 papers
21 papers
Black bounce solutions via nonminimal scalar-electrodynamic couplings
Daniela S. J. Cordeiro, Ednaldo L. B. Junior, José Tarciso S. S. Junior +5
Black-bounce (BB) solutions generalize the spacetimes of black holes, regular black holes, and wormholes, depending on the values of certain characteristic parameters. In this work…
Accretion dynamics in black holes with spontaneous Lorentz symmetry breaking
Daniela S. J. Cordeiro, Ednaldo L. B. Junior, José Tarciso S. S. Junior +6
We investigate the spherical accretion of various types of fluids onto a Schwarzschild-like black hole solution modified by a Kalb-Ramond field implementing spontaneous Lorentz sym…
Free-falling test particles in a charged Kalb-Ramond black hole: gravitational Doppler effect and tidal forces
Daniela S. J. Cordeiro, Ednaldo L. B. Junior, José Tarciso S. S. Junior +5
Space-times exhibiting spontaneous Lorentz symmetry-breaking have recently attracted much attention, with Kalb-Ramond (KR) gravity providing a notable example. In this context, we…
Dyonic regular black bounce solutions in General Relativity
Ednaldo L. B. Junior, José Tarciso S. S. Junior, Francisco S. N. Lobo +3
This work explores dyonic black bounce (BB) solutions within the framework of General Relativity (GR), coupled with nonlinear electrodynamics (NLED) and scalar fields (SFs). Previo…
The time-dependent quantum harmonic oscillator: a pedagogical approach via the Lewis-Riesenfeld dynamical invariant method
Stanley S. Coelho, Lucas Queiroz, Danilo T. Alves
In quantum mechanics courses, students often solve the Schrödinger equation for the harmonic oscillator with time-independent parameters. However, time-dependent quantum harmonic o…
Inverse magnetic catalysis and size-dependent effects on the chiral symmetry restoration
Luciano M. Abreu, Emerson B. S. Corrêa, Elenilson S. Nery
We investigate the combined finite-size and thermo-magnetic effects on the properties of the quark matter, in the context of the two-flavored Nambu--Jona-Lasinio model. In particul…
Simulation of machine learning-based 6G systems in virtual worlds
Ailton Oliveira, Felipe Bastos, Isabela Trindade +5
Digital representations of the real world are being used in many applications, such as augmented reality. 6G systems will not only support use cases that rely on virtual worlds but…
Rotation signature of TESS B-type stars. A comprehensive analysis
L. F. Barraza, R. L. Gomes, Y. S. Messias +11
Stellar rotation is a fundamental observable that drives different aspects of stellar and planetary evolution. In this work, we present an unprecedented manifold analysis of 160 B-…
-nilpotency criteria for some verbal subgroups
Yerko Contreras Rojas, Valentina Grazian, Carmine Monetta
Let be a finite group, let be a prime and let be a group-word. We say that satisfies if the prime divides the order of for every -value in…
On the multiscale behaviour of stellar activity and rotation of the planet host Kepler-30
D. B. de Freitas, A. F. Lanza, F. O. da Silva Gomes +1
Kepler-30 is a unique target to study stellar activity and rotation in a young solar-like star accompanied by a compact planetary system. We use about 4 years of high-precision pho…
Relativistic bands in the discrete spectrum of created particles in an oscillating cavity
Danilo T. Alves, Edney R. Granhen, João Paulo da S. Alves +1
We investigate the dynamical Casimir effect for a one-dimensional resonant cavity, with one oscillating mirror. Specifically, we study the discrete spectrum of created particles in…
Boundary effects on constituent quark masses and on chiral susceptibility in a four-fermion interaction model
L. M. Abreu, E. B. S. Corrêa, E. S. Nery
In this work we investigate the finite-size effects on the phase structure of a two-flavor four-fermion interaction model with a flavor-mixing four-body interaction and in the pres…
Multifractal detrended moving average analysis of Kepler stars with surface differential rotation traces
D. B. de Freitas, M. M. F. Nepomuceno, J. G. Cordeiro +2
A multifractal formalism is employed to analyse high-precision time-series data of \textit{Kepler} stars with surface differential rotation traces. The multifractal detrended movin…
New Suns in the Cosmos V: Stellar rotation and multifractality in active \textit{Kepler} stars
D. B. de Freitas, M. M. F. Nepomuceno, L. D. Alves Rios +2
In the present study, high-precision time series photometry for the active \emph{Kepler} stars is described in the language of multifractals. We explore the potential of using the…
Debris disks among Kepler solar rotational analog stars
R. Silva Sobrinho, A. D. Da Costa, B. L. Canto Martins +8
Observations of circumstellar disks provide a powerful tool for our understanding of planetary systems dynamics. Analogs to the Solar System asteroid belts, debris disks result fro…
Micromagnetic study of skyrmion stability in confined magnetic structures with perpendicular anisotropy
R. L. Novak, F. Garcia, E. R. P. Novais +2
Skyrmions are emerging topological spin structures that are potentially revolutionary for future data storage and spintronics applications. The existence and stability of skyrmions…
Controllability of Linear Control Systems on Solvable Lie Groups with Hyperbolic Drift
S. N. Stelmastchuk
We study the controllability of linear control systems on connected solvable Lie groups with hyperbolic drift. Under a suitable splitting assumption on the control directions, we s…
New Suns in the Cosmos IV: the multifractal nature of stellar magnetic activity in \textit{Kepler} cool stars
D. B. de Freitas, M. M. F. Nepomuceno, M. Gomes de Souza +5
In the present study, we investigate the multifractal nature of a long-cadence time series observed by the \textit{Kepler} mission for a sample of 34 M dwarf stars and the Sun in i…
A Model to Study Finite-Size and Magnetic Effects on the Phase Transition of a Fermion Interacting System
Emerson B. S. Corrêa, César A. Linhares, Adolfo P. C. Malbouisson
We present a model to study effects from an external magnetic field, chemical potential, and finite size, on the phase structure of a massive four- and six-fermion interacting syst…
New Suns in the Cosmos II: Differential rotation in Kepler Sun-like stars
M. L. Das Chagas, J. P. Bravo, A. D. Costa +9
The present study reports the discovery of Sun-like stars, namely main-sequence stars with , and rotation periods similar to solar values, presentin…
Topological conjugacy of linear systems on Lie groups
A. Da Silva, A. J. Santana, S. N. Stelmastchuk
In this paper we study a classification of linear systems on Lie groups with respect to the conjugacy of the corresponding flows. We also describe stability according to Lyapunov e…