Records |
Author |
Araujo Filho, A.A.; Hassanabadi, H.; Heidari, N.; Kriz, J.; Zare, S. |
Title |
Gravitational traces of bumblebee gravity in metric-affine formalism |
Type |
Journal Article |
Year |
2024 |
Publication |
Classical and Quantum Gravity |
Abbreviated Journal |
Class. Quantum Gravity |
Volume |
41 |
Issue |
5 |
Pages |
055003 - 21pp |
Keywords |
bumblebee gravity; metric affine formalism; shadows |
Abstract |
This work explores various manifestations of bumblebee gravity within the metric-affine formalism. We investigate the impact of the Lorentz violation parameter, denoted as X, on the modification of the Hawking temperature. Our calculations reveal that as X increases, the values of the Hawking temperature attenuate. To examine the behavior of massless scalar perturbations, specifically the quasinormal modes, we employ the Wentzel-Kramers-Brillouin method. The transmission and reflection coefficients are determined through our calculations. The outcomes indicate that a stronger Lorentz-violating parameter results in slower damping oscillations of gravitational waves. To comprehend the influence of the quasinormal spectrum on time-dependent scattering phenomena, we present a detailed analysis of scalar perturbations in the time-domain solution. Additionally, we conduct an investigation on shadows, revealing that larger values of X correspond to larger shadow radii. Furthermore, we constrain the magnitude of the shadow radii using the EHT horizon-scale image of SgrA* . Finally, we calculate both the time delay and the deflection angle. |
Address |
[Araujo Filho, A. A.] Univ Valencia, CSIC, Dept Fis Teor, Ctr MIxto Univ Valencia, Burjassot 46100, Valencia, Spain, Email: dilto@fisica.ufc.br |
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing Ltd |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0264-9381 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:001152994800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5925 |
Permanent link to this record |
|
|
|
Author |
Amarilo, K.M.; Ferreira Filho, M.B.; Araujo Filho, A.A.; Reis, J.A.A.S. |
Title |
Gravitational waves effects in a Lorentz-violating scenario |
Type |
Journal Article |
Year |
2024 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
855 |
Issue |
|
Pages |
138785 - 7pp |
Keywords |
Gravitational waves; Lorentz symmetry breaking; Polarization states; Quadrupole term |
Abstract |
This paper focuses on how the production and polarization of gravitational waves are affected by spontaneous Lorentz symmetry breaking, which is driven by a self-interacting vector field. Specifically, we examine the impact of a smooth quadratic potential and a non-minimal coupling, discussing the constraints and causality features of the linearized Einstein equation. To analyze the polarization states of a plane wave, we consider a fixed vacuum expectation value (VEV) of the vector field. Remarkably, we verify that a space-like background vector field modifies the polarization plane and introduces a longitudinal degree of freedom. In order to investigate the Lorentz violation effect on the quadrupole formula, we use the modified Green function. Finally, we show that the space-like component of the background field leads to a third-order time derivative of the quadrupole moment, and the bounds for the Lorentz-breaking coefficients are estimated as well. |
Address |
[Amarilo, K. M.; Ferreira Filho, M. B.] Univ Estado Rio de Janeiro, Dep Fis Nucl & Altas Energias, Inst Fis, Rua Sao Francisco Xavier 524, BR-20559900 Rio De Janeiro, RJ, Brazil, Email: kevin.amarilo@cern.ch; |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0370-2693 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:001257664300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6168 |
Permanent link to this record |
|
|
|
Author |
Araujo Filho, A.A. |
Title |
Implications of a Simpson-Visser solution in Verlinde's framework |
Type |
Journal Article |
Year |
2024 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
84 |
Issue |
1 |
Pages |
73 - 22pp |
Keywords |
|
Abstract |
This study focuses on investigating a regular black hole within the framework of Verlinde's emergent gravity. In particular, we explore the main aspects of the modified Simpson-Visser solution. Our analysis reveals the presence of a unique physical event horizon under certain conditions. Moreover, we study the thermodynamic properties, including the Hawking temperature, the entropy, and the heat capacity. Based on these quantities, our results indicate several phase transitions. Geodesic trajectories for photon-like particles, encompassing photon spheres and the formation of black hole shadows, are also calculated to comprehend the behavior of light in the vicinity of the black hole. Additionally, we also provide the calculation of the time delay and the deflection angle. Corroborating our results, we include an additional application in the context of high-energy astrophysical phenomena: neutrino energy deposition. Finally, we investigate the quasinormal modes using third-order WKB approximation. |
Address |
[Filho, A. A. Araujo] Univ Valencia, CSIC, Ctr Mixto Univ Valencia, Dept Fis Teor, Burjassot 46100, Valencia, Spain, Email: dilto@fisica.ufc.br |
Corporate Author |
|
Thesis |
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:001147924500002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5916 |
Permanent link to this record |
|
|
|
Author |
Araujo Filho, A.A.; Reis, J.A.A.S.; Ghosh, S. |
Title |
Quantum gases on a torus |
Type |
Journal Article |
Year |
2023 |
Publication |
International Journal of Geometric Methods in Modern Physics |
Abbreviated Journal |
Int. J. Geom. Methods Mod. Phys. |
Volume |
20 |
Issue |
10 |
Pages |
2350178 - 19pp |
Keywords |
Thermodynamic properties; non-Cartesian geometries; grand canonical ensemble; noninteracting and interacting quantum gases; spinless; bosons and fermion particles |
Abstract |
This paper is aimed at studying the thermodynamic properties of quantum gases confined to a torus. To do that, we consider noninteracting gases within the grand canonical ensemble formalism. In this context, fermions and bosons are taken into account and the calculations are properly provided in both analytical and numerical manners. In particular, the system turns out to be sensitive to the topological parameter under consideration: the winding number. Furthermore, we also derive a model in order to take into account interacting quantum gases. To corroborate our results, we implement such a method for two different scenarios: a ring and a torus. |
Address |
[Araujo Filho, A. A.] Univ Fed Ceara UFC, Dept Fis, Campus Pici,CP 6030, BR-60455760 Fortaleza, CE, Brazil, Email: dilto@fisica.ufc.br; |
Corporate Author |
|
Thesis |
|
Publisher |
World Scientific Publ Co Pte Ltd |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0219-8878 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000988814200003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5553 |
Permanent link to this record |
|
|
|
Author |
Silva, J.E.G.; Yesiltas, O.; Furtado, J.; Araujo Filho, A.A. |
Title |
Strain effects on the electronic properties of a graphene wormhole |
Type |
Journal Article |
Year |
2024 |
Publication |
European Physical Journal Plus |
Abbreviated Journal |
Eur. Phys. J. Plus |
Volume |
139 |
Issue |
8 |
Pages |
762 - 16pp |
Keywords |
|
Abstract |
In this work, we explore the strain and curvature effects on the electronic properties of a curved graphene structure, called the graphene wormhole. The electron dynamics is described by a massless Dirac fermion containing position-dependent Fermi velocity. In addition, the strain produces a pseudo-magnetic vector potential to the geometric coupling. For an isotropic strain tensor, the decoupled components of the spinor field exhibit a supersymmetric (SUSY) potential, depending on the centrifugal term and the external magnetic field only. In the absence of an external magnetic field, the strain yields an exponentially damped amplitude, whereas the curvature leads to a power-law damping of the wave function. The spin-curvature coupling breaks the chiral symmetry between the upper and the lower spinor component, which leads to the increasing of the wave function on either upper or lower region of the wormhole, i.e., depending on the spin number. By adding a uniform magnetic field, the effective potential exhibits an asymptotic quadratic profile and a spin-curvature barrier near the throat. As a result, the bound states (Landau levels) are confined around the wormhole throat showing an asymmetric and spin-dependent profile. |
Address |
[Silva, J. E. G.] Univ Fed Ceara, Dept Fis, BR-60455760 Fortaleza, CE, Brazil, Email: euclides@fisica.ufc.br; |
Corporate Author |
|
Thesis |
|
Publisher |
Springer Heidelberg |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2190-5444 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:001297836200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6247 |
Permanent link to this record |