Roldão da Rocha
Universidade Federal do ABC
H-index: 44
Latin America-Brazil
About Roldão da Rocha
Roldão da Rocha, With an exceptional h-index of 44 and a recent h-index of 32 (since 2020), a distinguished researcher at Universidade Federal do ABC, specializes in the field of Gauge/Gravity dualities, High energy physics, Black hole physics, Mathematical-Physics.
His recent articles reflect a diverse array of research interests and contributions to the field:
Thermodynamic and configurational entropy of quantum Schwarzschild geometries
Quantum hair and entropy for slowly rotating quantum black holes
Generalized extremal branes in AdS/CMT and holographic superconductors
Emergent spinor fields from exotic spin structures
When gravitational decoupling and quantum gravity (re) unite
Quark stars in – holographic model
Gravitational decoupling and aerodynamics: black holes and analog gravity in a jet propulsion lab
Configurational entropy of black hole quantum cores
Roldão da Rocha Information
University | Universidade Federal do ABC |
---|---|
Position | ___ |
Citations(all) | 5453 |
Citations(since 2020) | 3264 |
Cited By | 3742 |
hIndex(all) | 44 |
hIndex(since 2020) | 32 |
i10Index(all) | 122 |
i10Index(since 2020) | 73 |
University Profile Page | Universidade Federal do ABC |
Roldão da Rocha Skills & Research Interests
Gauge/Gravity dualities
High energy physics
Black hole physics
Mathematical-Physics
Top articles of Roldão da Rocha
Thermodynamic and configurational entropy of quantum Schwarzschild geometries
Authors
Roberto Casadio,Roldão da Rocha,Andrea Giusti,Pedro Meert
Journal
Physics Letters B
Published Date
2024/2/1
We study different entropies for coherent states representing the geometry of spherically symmetric compact systems. We show that the thermodynamic entropy reproduces the Bekenstein-Hawking result in the presence of thermal modes at the Hawking temperature if the object is a black hole and saturates the Bekenstein bound for more general compact objects. We also analyse the information entropy of the quantum coherent state without radiation and find further support against the singular Schwarzschild geometry.
Quantum hair and entropy for slowly rotating quantum black holes
Authors
Wenbin Feng,Roldao da Rocha,Roberto Casadio
Journal
arXiv preprint arXiv:2401.14540
Published Date
2024/1/25
We study the quantum hair associated with coherent states describing slowly rotating black holes and show how it can be naturally related with the Bekenstein-Hawking entropy and with 1-loop quantum corrections of the metric for the (effectively) non-rotating case. We also estimate corrections induced by such quantum hair to the temperature of the Hawking radiation through the tunnelling method.
Generalized extremal branes in AdS/CMT and holographic superconductors
Authors
Roldao da Rocha
Journal
Annals of Physics
Published Date
2024/4/15
AdS 4 generalized extremal branes are scrutinized in the context of AdS/CFT. Holographic superconductors are studied as dual objects to AdS 4 generalized extremal branes, whose coefficients of response and transport in the dual condensed matter theory are calculated and discussed. The holographic Weyl anomaly is also addressed. The holographic superconductor bound current is shown to be enhanced by the parameter controlling the family of AdS 4 generalized extremal branes, when compared to the standard AdS 4-Reissner–Nordström black brane results. In the probe limit, the electrical DC conductivity for holographic superconductors with AdS 4 generalized extremal brane dual background is also reported.
Emergent spinor fields from exotic spin structures
Authors
JM Hoff da Silva,R da Rocha
Journal
Progress of Theoretical and Experimental Physics
Published Date
2024/4/10
The classification of emergent spinor fields according to modified bilinear covariants is scrutinized, in spacetimes with nontrivial topology, which induce inequivalent spin structures. Extended Clifford algebras, constructed by equipping the underlying spacetime with an extended bilinear form with additional terms coming from the nontrivial topology, naturally yield emergent extended algebraic spinor fields and their subsequent extended bilinear covariants, which are contrasted to the classical spinor classification. An unexpected duality between the standard and the exotic spinor field classes is therefore established, showing that a complementary fusion process among the spinor field classes sets in, when extended Clifford bundles are addressed in multiply-connected spacetimes.
When gravitational decoupling and quantum gravity (re) unite
Authors
R Casadio,I Kuntz,R da Rocha
Journal
arXiv preprint arXiv:2403.13099
Published Date
2024/3/19
The effective action for quantum gravity coupled to matter contains corrections arising from the functional measure. We analyse the effect of such corrections for anisotropic self-gravitating compact objects described by means of the gravitational decoupling method applied to isotropic solutions of the Einstein field equations. In particular, we consider the Tolman IV solution of general relativity and show that quantum gravity effects can modify the effective energy density as well as the effective tangential and radial pressures. For a suitable choice of the mimicking constant, upper bounds on the quantum corrections can be driven by the surface redshift of the anisotropic compact stellar system obtained with the gravitational decoupling.
Quark stars in – holographic model
Authors
M Aleixo,CH Lenzi,W de Paula,R da Rocha
Journal
The European Physical Journal C
Published Date
2024/3/11
This work investigates static and dynamical quark star properties within a holographic model. We solve the Tolman–Oppenheimer–Volkoff equations for the quark matter equation of state obtained from the brane configuration. We determine the mass-radius diagram for a range of model parameters and compare with recent NICER observational data for the pulsars PSR J and PSR J Motivated by the GW170817 event detected by the LIGO-Virgo collaboration, we also calculate the tidal deformability parameter obtained for each component of the binary star system. We show that quark stars composed of flavor-independent quark matter derived from the holographic model are not able to satisfy simultaneously the LIGO-Virgo and NICER astrophysical bounds.
Gravitational decoupling and aerodynamics: black holes and analog gravity in a jet propulsion lab
Authors
R Casadio,C Noberto Souza,R da Rocha
Journal
arXiv preprint arXiv:2402.04682
Published Date
2024/2/7
A connection is established between transonic sound waves propagating along a de Laval nozzle and quasinormal modes emitted from hairy black holes obtained with the gravitational decoupling method applied to the Reissner-Nordstr\"om geometry. Aerodynamical features provide an analogue setup to experimentally test fluid flow perturbations in a de Laval nozzle producing quasinormal modes. In particular, nozzle shape, pressure, Mach number, temperature, density, and thrust coefficient profiles are determined as functions of the black hole parameters for several multipole numbers. The black hole quasinormal mode frequencies are also investigated for different overtones, evaluating the quality factor of the nozzle.
Configurational entropy of black hole quantum cores
Authors
R Casadio,R da Rocha,P Meert,L Tabarroni,W Barreto
Journal
Classical and Quantum Gravity
Published Date
2023/3/14
Two types of information entropy are studied for the quantum states of a model for the matter core inside a black hole geometry. A detailed description is first given of the quantum mechanical picture leading to a spectrum of bound states for a collapsing ball of dust in general relativity with a non-trivial ground state. Information entropies are then computed, shedding new light on the stability of the ground state and the spectrum of higher excited states.
On valley asymmetry in a topological interaction for quasi-particles
Authors
GB de Gracia,BM Pimentel,R da Rocha
Journal
Annals of Physics
Published Date
2023/12/1
This paper is focused on investigating the effects of a statistical interaction for graphene-like systems, providing Haldane-like properties for topologically trivial lattices. The associated self-energy correction yields an effective next-nearest hopping, inducing the topological phase, whose specific solutions are scrutinized. In the case of an external magnetic field, it leads to a renormalized quasi-particle structure with generalized Landau levels and explicit valley asymmetry. A suitable tool for implementing such achievements is a judicious indefinite metric quantization, leading to advances in field theory foundations. Since the topological behavior is encoded in the radiative corrections, an unequivocal treatment using an integral representation is carefully developed.
Configurational information measure of mesonic states in 4-flavor AdS/QCD
Authors
G Karapetyan,W de Paula,R da Rocha
Journal
Physics Letters B
Published Date
2023/11/10
Strange axial-vector kaons, K 1, and f 1 meson resonances are investigated in the 4-flavor AdS/QCD model. Their underlying differential configurational entropy is computed and the mass spectra of higher-excited resonances, in both these mesonic families, are achieved and discussed. This technique merges the 4-flavor AdS/QCD and experimental data regarding the mass spectrum of K 1 and f 1 meson resonances that have been already detected and reported in the Particle Data Group, also bringing forth a route to explore physical features of the next generation of resonances in the K 1 and f 1 meson families.
New constrained generalized Killing spinor field classes in warped flux compactifications
Authors
D Fabri Gonçalves,R da Rocha
Journal
arXiv preprint arXiv:2310.19530
Published Date
2023/10/30
The generalized Fierz identities are addressed in the K\"ahler-Atiyah bundle framework from the perspective of the equations governing constrained generalized Killing spinor fields. We explore the spin geometry in a Riemannian 8-manifold composing a warped flux compactification AdS, whose metric and fluxes preserve one supersymmetry in AdS. Supersymmetry conditions can be efficiently translated into spinor bilinear covariants, whose algebraic and differential constraints yield identifying new spinor field classes. Intriguing implications and potential applications are discussed.
Generalized black branes in AdS/CMT and holographic superconductors
Authors
Roldao da Rocha
Journal
arXiv preprint arXiv:2310.07860
Published Date
2023/10/11
AdS generalized black branes are scrutinized in the context of AdS/CFT. Holographic superconductors are studied as dual objects to AdS generalized black branes, whose coefficients of response and transport in the dual condensed matter theory are calculated and discussed. The holographic Weyl anomaly is also addressed. The holographic superconductor bound current is shown to be enhanced by the parameter controlling the family of AdS generalized black brane solutions, when compared to the standard AdS-Reissner-Nordstr\"om black brane results. In the probe limit, the electrical DC conductivity for holographic superconductors with AdS generalized black brane dual background is also reported.
Configurational entropy and shape complexity of strange vector kaons in AdS/QCD
Authors
Roldao da Rocha,Pedro HO Silva
Journal
The European Physical Journal Plus
Published Date
2023/8/1
The mass spectrum of strange vector kaons resonances is scrutinized, using AdS/QCD with a deformed dilaton that arises from the constituent quark masses. Both the differential configurational entropy and the differential configurational complexity are computed and used to achieve the mass spectrum of strange vector kaons resonances with higher radial quantum numbers. This approach amalgamates AdS/QCD and the experimental mass spectrum of already detected strange vector kaons in the Particle Data Group, providing a hybrid technique to study the next generation of strange vector kaons resonances.
Transport coefficients in AdS/CFT and quantum gravity corrections due to a functional measure
Authors
Iberê Kuntz,Roldao da Rocha
Journal
Nuclear Physics B
Published Date
2023/8/1
The presence of a functional measure is scrutinized on both sides of the dual gauge/gravity correspondence. Corrections to the transport coefficients in relativistic hydrodynamics are obtained using the linear response procedure. In particular, using first-order hydrodynamics, the shear viscosity, entropy density, diffusion constant, and speed of sound are shown not to acquire any corrections from the functional measure of gravity, for a Minkowski background metric. On the other hand, the energy density, the pressure, the relaxation time, the bulk viscosity, the decay rate of sound waves, and coefficients of conformal traceless tensor fields, are shown to carry significant quantum corrections due to the functional measure, even for a flat background. They all acquire an imaginary part that reflects the instability of the strongly-coupled fluids on the boundary CFT. This opens up the possibility of testing quantum gravity with …
Fermionic dark matter-photon quantum interaction: A mechanism for darkness
Authors
GB de Gracia,AA Nogueira,R da Rocha
Journal
Nuclear Physics B
Published Date
2023/7/1
Mass dimension one fermionic fields are prime candidates to describe dark matter, due to their intrinsic neutral nature, as they are constructed as eigenstates of the charge conjugation operator with dual helicity. To formulate the meaning of the darkness, the fermion-photon coupling is scrutinized with a Pauli-like interaction, and the path integral is then formulated from the phase space constraint structure. Ward–Takahashi-like identities and Schwinger–Dyson equations, together with renormalizability, are employed to investigate a phenomenological mechanism to avoid external light signals. Accordingly, the non-polarized pair annihilation and Compton-like processes are shown to vanish at the limit of small scattering angles even if considering 1-loop radiative corrections, reinforcing the dark matter interpretation. However, dark matter interactions with nucleons are still possible. Motivated by recent nucleon-recoil …
Information entropy of nuclear electromagnetic transitions in AdS/QCD
Authors
Roldao da Rocha
Journal
Nuclear Physics B
Published Date
2023/7/1
Electromagnetic transitions involving nucleons and their resonances are here presented in the fermionic sector of the AdS/QCD soft-wall model, using the differential configurational entropy (DCE) as a measure of information entropy. The DCE is employed to derive adjustable parameters that define the minimal and nonminimal couplings in the nuclear interaction with a gauge vector field, in the nucleonic γ N→ N⁎(1535) transition. The values obtained comply with phenomenological data with good accuracy.
Axion stars in MGD background
Authors
Roberto Casadio,R da Rocha
Journal
The European Physical Journal C
Published Date
2023/6
The minimal geometric deformation (MGD) paradigm is here employed to survey axion stars on fluid branes. The finite value of the brane tension provides beyond-general relativity corrections to the density, compactness, radius, and asymptotic limit of the gravitational mass function of axion stars, in a MGD background. The brane tension also enhances the effective range and magnitude of the axion field coupled to gravity. MGD axion stars are compatible to mini-massive compact halo objects for almost all the observational range of brane tension, however, a narrow range allows MGD axion star densities large enough to produce stimulated decays of the axion to photons, with no analogy in the general-relativistic (GR) limit. Besides, the gravitational mass and the density of MGD axion stars are shown to be up to four orders of magnitude larger than the GR axion stars, being also less sensitive to tidal disruption …
Holographic entanglement entropy, deformed black branes, and deconfinement in AdS/QCD
Authors
Roldao da Rocha
Journal
Physical Review D
Published Date
2022/1/11
A family of deformed black branes is employed to examine the confinement/deconfinement phase transition in AdS/QCD. The holographic entanglement entropy (HEE) plays the role of the order parameter driving the confinement/deconfinement phase transition. The binding energy of quark-antiquark bound states and the critical length that makes a null variation of the HEE, together with the critical temperature separating the deconfined quark-gluon plasma to the confined hadronic phase, are discussed in the deformed black brane background, matching current experimental hadronic data.
Configurational entropy of generalized sine–Gordon-type models
Authors
W Barreto,A Herrera–Aguilar,R da Rocha
Journal
Annals of Physics
Published Date
2022/12/1
A family of deformed models of the sine–Gordon-type can be generated by twisting the sine–Gordon model. As a particular case, the 3-sine–Gordon model is here addressed, whose differential configurational entropy and the differential configurational complexity of three topological sectors are discussed using two complementary approaches. Stability aspects are also discussed.
Gravitational decoupling of generalized Horndeski hybrid stars
Authors
Roldao da Rocha
Journal
The European Physical Journal C
Published Date
2022/1
Gravitational decoupled compact polytropic hybrid stars are here addressed in generalized Horndeski scalar-tensor gravity. Additional physical properties of hybrid stars are scrutinized and discussed in the gravitational decoupling setup. The asymptotic value of the mass function, the compactness, and the effective radius of gravitational decoupled hybrid stars are studied for both cases of a bosonic and a fermionic prevalent core. These quantities are presented and discussed as functions of Horndeski parameters, the decoupling parameter, the adiabatic index, and the polytropic constant. Important corrections to general relativity and generalized Horndeski scalar-tensor gravity, induced by the gravitational decoupling, comply with available observational data. Particular cases involving white dwarfs, boson stellar configurations, neutron stars, and Einstein–Klein–Gordon solutions, formulated in the gravitational …
Roldão da Rocha FAQs
What is Roldão da Rocha's h-index at Universidade Federal do ABC?
The h-index of Roldão da Rocha has been 32 since 2020 and 44 in total.
What are Roldão da Rocha's top articles?
The articles with the titles of
Thermodynamic and configurational entropy of quantum Schwarzschild geometries
Quantum hair and entropy for slowly rotating quantum black holes
Generalized extremal branes in AdS/CMT and holographic superconductors
Emergent spinor fields from exotic spin structures
When gravitational decoupling and quantum gravity (re) unite
Quark stars in – holographic model
Gravitational decoupling and aerodynamics: black holes and analog gravity in a jet propulsion lab
Configurational entropy of black hole quantum cores
...
are the top articles of Roldão da Rocha at Universidade Federal do ABC.
What are Roldão da Rocha's research interests?
The research interests of Roldão da Rocha are: Gauge/Gravity dualities, High energy physics, Black hole physics, Mathematical-Physics
What is Roldão da Rocha's total number of citations?
Roldão da Rocha has 5,453 citations in total.