arXiv subjects

J. Andrade

Publications and source records attributed to J. Andrade.

8 recordsLinked to original sources

arXiv2026

Particle Dynamics and Thermodynamics of a Charged-Like Hairy Black Hole in Extended Gravitational Decoupling

This work focuses on the analysis of particle dynamics and the thermodynamic properties associated with a particular branch of hairy black hole solutions. These solutions are obtained by using extended geometric deformation gravitational decoupling on the seed solution of the Schwarzschild solution. This resulting geometry satisfies the dominant energy condition and the condition $Q^{2}=2\chi\ell M$. We analyze the motion of massive particles and photons in this geometry and the thermodynamics of this solution. In particular, for massless particles, we study the effective potential and determine the radii of the photon sphere and the shadow of the black hole. For massive particles, we calculate the specific energy and angular momentum of circular orbits, the ISCO, the radiative efficiency of an accretion disk, and representative particle trajectories. Finally, we investigate the thermodynamic properties of this hairy black hole geometry, including the Hawking temperature, the Bekenstein-Hawking entropy, and the heat capacity in the fixed-$(Q,\ell)$ ensemble.

gr-qc↗

arXiv2026

Reeb-Wolf Improved Landauer Principle for Hairy Black Holes via Gravitational Decoupling

We investigated the thermodynamic and quantum-information cost of irreversible information erasure at the event horizon of hairy black holes generated through extended geometric deformation. Starting from the Schwarzschild black hole seed solution, we considered two families of hairy geometries satisfying the strong and dominant energy conditions. Lan-dauer's principle was used to relate the minimum energy required to erase one bit of information to the Hawking temperature of deformed horizon. We derived corresponding horizon radii, Hawking temperatures, Bekenstein-Hawking entropies and normalised Landauer costs as functions of decoupling parameter, the hair length scale and the effective charge associated with the additional gravitational sector. For the parameter ranges analyzed, our results show that gravitational hair tends to reduce the Hawking temperature and the minimum Landauer erasure cost while simultaneously increasing the horizon area and the Bekenstein-Hawking entropy. The Reeb-Wolf finite-size correction provides an additional positive contribution to the erasure cost but remains subdominant due to the large effective dimension of the horizon reservoir. We further separated the Reeb-Wolf correction into mutual-information and relative-entropy contributions, showing that the former is governed by the area-spacing parameter, whereas the latter is controlled by the actual energy gap between neighboring horizon levels. Furthermore, the Landauer spectrum obtained by quantizing the area decreases as the quantum number associated with the horizon increases, although this variation does not occur in the same way in the SEC and DEC branches. Overall, the presence of gravitational hair alters the thermodynamic properties of the horizon and, consequently, the Landauer cost associated with information erasure, both in the continuous regime and after quantizing the area.

gr-qc↗

arXiv2024

Restricted baby Skyrme-Maxwell theory in a magnetic medium: BPS configurations and some properties

We study the existence of BPS configurations in a restricted baby Skyrme-Maxwell enlarged via the inclusion of a nontrivial magnetic permeability. In order to attain such a goal, we use the Bogomol'nyi-Prasad-Sommerfield prescription, which allows us to obtain the lower bound for the energy and the BPS equations whose [electrically neutral] solutions saturate that bound. During the energy minimization procedure, we find a differential constraint which involves the self-dual potential, the superpotential itself and also the magnetic permeability. In order to solve the BPS system, we focus our attention on those solutions with rotational symmetry. For that, we fix the magnetic permeability and select two BPS potentials which exhibit a similar behavior near to the vacuum. We depict the resulting profiles and proceed to an analytical description of the properties of the BPS magnetic field. Furthermore, we consider some essential aspects of our model, such as the conditions for the overall existence of the BPS solutions, and how the permeability affects the magnetic flux. Finally, we present a family of exact BPS solutions.

hep-th↗

arXiv2024

BPS chiral vortices in a Maxwell-Higgs electrodynamics

We investigate the existence of BPS structures in a Maxwell-Higgs electrodynamics immersed within a chiral medium, whose electromagnetic properties are described by both the Chern-Simons term and a neutral scalar field. The implementation of the Bogomol'nyi-Prasad-Sommerfield's technique provides the BPS potential and the self-dual equations whose solutions saturate the Bogomol'nyi bound. In such a context, we look for vortices in two chiral media: the first one engenders localized vortices with an exponential decay similar to that of the Abrikosov-Nielsen-Olesen solutions, whereas the second medium generates delocalized profiles whose tail follows a power-law decay. Once we have solved the BPS systems, we comment on the effects induced by the presence of the chiral medium on the Maxwell-Higgs vortices.

hep-th↗

arXiv2022

BPS solitons with internal structures in a restricted baby Skyrme-Maxwell theory in a magnetic medium

We consider a restricted baby Skyrme-Maxwell scenario enlarged via the inclusion of a nontrivial magnetic permeability. We then proceed with the minimization of its total energy by means of the Bogomol'nyi-Prasad-Sommerfield (BPS) prescription, from which we get that the self-dual potential now depends on the magnetic permeability itself. As a result, we obtain not only the lower bound for the energy, but also the self-dual equations whose solutions saturate that bound. In such a context, we focus our attention on those time-independent gauged skyrmions with radial symmetry and no electric charge. We solve the effective self-dual equations numerically for different choices of the magnetic permeability, from which we obtain BPS magnetic fields whose internal structures form concentric rings. We also explain analytically the formation of these structures based on the values of a single real parameter which characterizes the respective magnetic permeabilities.

hep-th↗

arXiv2021

Stellar models with like--Tolman IV complexity factor

In this work, we construct stellar models ba-\break sed on the complexity factor as a supplementary condition which allows to close the system of differential equations arising from the Gravitational Decoupling. The assumed complexity is a generalization of the one obtained from the well known Tolman IV solution. We use Tolman IV, Wyman IIa, Durgapal IV and Heintzmann IIa as seeds solutions. Reported compactness parameters of SMC X-1 and Cen X-3 are used to study the physical acceptability of the models. Some aspects related to the density ratio are also discussed.

gr-qc↗

arXiv2020

BPS Maxwell-Chern-Simons vortices with internal structures: the Abelian Higgs and the gauged $CP(2)$ cases

We investigate the existence of first-order vortices inherent to both the Maxwell-Chern-Simons-Higgs and the Maxwell-Chern-Simons-$CP(2)$ models extended via the inclusion of an extra scalar sector which plays the role of a source field. For both cases, we focus our attention on the time-independent configurations with radial symmetry which can be obtained through the implementation of the so-called Bogomol'nyi-Prasad-Sommerfield (BPS) prescription. In this sense, in order to solve the corresponding first-order differential equations, we introduce some particular scenarios which are driven by the source field whose presence, we expect, must change the way the resulting vortices behave. After solving the effective first-order system through a finite-difference algorithm, we comment about the main new effects induced by the presence of the source field in the shape of the final configurations.

hep-th↗

arXiv2019

First-order solitons with internal structures in an extended Maxwell-$CP(2)$ model

We study a Maxwell-$CP(2)$ model coupled to a real scalar field through a dielectric function multiplying the Maxwell term. In such a context, we look for first-order rotationally symmetric solitons by means of the Bogomol'nyi algorithm, i.e. by minimizing the total energy of the effective model. We perform our investigation by choosing an explicit form of the dielectric function. The numerical solutions show regular vortices whose shapes dramatically differ from their canonical counterparts. We can understood such differences as characterizing the existence of an internal structure.

hep-th↗