arXiv subjects

Henrique Boschi-Filho

Publications and source records attributed to Henrique Boschi-Filho.

At least 19 recordsLinked to original sources

arXiv2026

Nucleon spectra and wave functions from holographic models with dual Einstein-dilaton and Starobinsky-dilaton gravities

We study the nucleon spectra in two holographic set-ups: Einstein-dilaton and Starobinsky-dilaton gravity models. The Einstein-dilaton holographic model, also known as improved holographic QCD, have been proposed some time ago to describe confinement and glueball spectra. Recently, it has been applied to the case of mesons and nucleons. In this work, we reconsider the Einstein-dilaton holographic model to discuss the nucleon spectra introducing new parameters that allow us to improve the comparison with experimental data. Then, we extend this idea to the context of Starobinsky-dilaton gravity defining another improved holographic model. We use this new holographic model to reanalyse the nucleon spectra and also compare them with soft-wall model and experimental data.

hep-th↗

arXiv2026

Building an AdS/BCFT Josephson junction within Horndeski gravity

This work explores the constriction and normal Josephson junctions of superconductors within Horndeski's gravitational theory framework. Through a single scalar field of this theory, we provide a dual holographic description via the AdS/BCFT correspondence. We identify a critical temperature below which a charged condensate forms through a second-order phase transition in constriction and normal junctions. Our findings reveal that the condensate comprises pairs of quasiparticles. The junctions between superconductors are characterized by weak links that lead to supercurrent flow, with their magnitude determined by the phase difference between the superconductors, which is modulated by the Horndeski parameters. The supercurrents are governed by the Josephson current-phase relation, highlighting the intricate interplay between gravitational theory and superconducting phenomena.

hep-th↗

arXiv2026

Mechanical properties of the proton from a deformed AdS holographic model

We study the gravitational form factors of the proton and some of its mechanical properties. We use a holographic model based on the AdS/CFT correspondence, in which a deformation in the anti-de Sitter background geometry is considered. By describing the proton as a Dirac field in this background, we numerically evaluate the gloun contribution of its gravitational form factors $A$ and $C$ from its energy-momentum tensor. A comparison of our numerical results with respect to some lattice QCD results and previous results in holography is made. In general, a good agreement is found. We also evaluate the term $D$ and make use of it to compute the pressure and shear distributions in the system, which result in a stable composed particle interpretation consistent with the von Laue stability condition. The energy distribution in the system is also obtained. Internal forces are investigated to support this picture. We are also able to compute the radii associated with these distributions in the proton.

hep-ph↗

arXiv2026

The connection between a classical vibrating drumhead and the masses of glueballs

The powerful techniques of holographic quantum chromodynamics (QCD) can be employed in the investigation of glueballs -- composite particles made solely of gluons, the strong nuclear force mediators. In particular, the so-called hardwall model yields predictions for the values of the masses of various glueball states, which are related to the solutions of the differential equations of the model. It turns out that those equations are essentially the same as the ones governing the vibrations of a circular membrane like that of a drumhead, which may serve as extra motivation for studying the dynamics of such an object as an undergraduate physics student.

hep-th↗

arXiv2026

Light baryon spectra and Regge trajectories from anomalous holographic hard wall models

In this work we propose anomalous versions of the holographic hard wall (HW) model to describe the spectra of light baryons of spin 1/2 and 3/2, and obtain their Regge trajectories. The anomalous contributions to the dimensions of the baryonic operators of logarithm form come from a semiclassical analysis of the AdS/CFT correspondence and were used recently for glueballs and light unflavoured mesons. Inspired by these results, we first propose an anomalous dimension of the form $Δ_{\rm anom.}=a\ln L +b$, where $a$ and $b$ are phenomenological constants to be adjusted numerically to better fit the experimental data of the PDG, and $L$ is the angular momentum of each baryonic state. Second, we discuss the case where the anomalous dimension also depends on the spin $S$ as $Δ_{\rm anom.}=a\ln (L+S+1/2) +b$, and fix the parameters $a$ and $b$ targeting PDG data. These two models, called AHW$_1$ and AHW$_2$, give better results for light baryon masses $(M)$ in comparison with the original HW model and show approximately linear Regge trajectories $(M^2\times L)$. We also consider a third anomalous HW model in which the dimension of the baryonic operator increases as $Δ_{\rm Lin.}=a L^c +b$, where $a$, $b$, and $c$ are constants adjusted to fit the light baryonic masses of PDG. Apart from compatible masses with PDG data, this case produces Regge trajectories that are asymptotically linear.

hep-ph↗

arXiv2026

Joule-Thomson expansion for quantum corrected AdS-Reissner-Nordström black holes in Kiselev spacetime with Barrow fractal entropy

Recently, Barrow proposed an extension of the Bekenstein-Hawking black hole entropy to include the effects of fractal geometry through a parameter $Δ$. Since then, several interesting issues related to this extended entropy have been explored in the literature. In this work, we investigate the effects of the fractal parameter $Δ$ on the inversion temperature connected to the Joule-Thomson expansion that can be obtained from the thermodynamics of AdS-Reissner-Nordström black holes in Kiselev spacetime. The description of such physical systems involves numerical solutions concerning the fractal parameter $Δ$. The results are shown by temperature-pressure curves for multiple values of the set of parameters that define the black hole thermodynamics. In conclusion of our analysis, we also show isenthalpic curves corresponding to fixed-mass black hole processes.

hep-th↗

arXiv2025

Proton Structure Functions from Holographic Einstein-Dilaton Models

We study the proton structure functions $F_1$ and $F_2$ in the context of holography. We develop a general framework that extends previous holographic calculations of $F_1$ and $F_2$ to the case where the bulk geometry stems from bottom-up Einstein-Dilaton models, which are commonly used in the literature to describe some properties of QCD in the strong coupling regime. We focus on a choice of the dilaton potential that leads to a holographic model able to reproduce known lattice QCD results for the glueball masses at zero temperature and pure Yang-Mills thermodynamics above deconfinement. Once the parameters of the background holographic model are fixed, we introduce probe fermionic and gauge fields in the bulk {\it a la} Polchinski and Strassler to determine the corresponding structure functions. This particular realization of the model can successfully describe the proton mass and provide results for $F_2$ at large $x$ in very good agreement with experimental data.

hep-th↗

arXiv2025

Geometric Josephson junction

In this work, we present a gravitational dual to a constriction Josephson junction constructed from the AdS/BCFT correspondence. On the gravity side, we consider a planar AdS-Schwarzschild black hole. Our junction is connected by the boundary $\partialΩ$ with tension $Σ$ on the boundary CFT. This approach lead us to analytical solutions rather than usual numerical methods. Our computations on the gravity side reproduce the standard relation between the current across the junction and the phase difference of the condensate controlled by the tension $Σ$. We also study the maximum current's dependence on the junction's tension and size and reproduce familiar results.

hep-th↗

arXiv2024

Anomalous and linear holographic hard wall models for light unflavored mesons

In this work we consider anomalous and linear holographic hard wall (HW) models for light unflavored mesons inspired by the AdS/CFT correspondence. The anomalous dimensions depend on the logarithm of the spin S of the meson state and come from a semiclassical analysis of gauge/string duality. The anomalous HW model produces very good masses and good Regge trajectories for mesons compared with PDG data. Inspired by this anomalous HW model we also propose a phenomenological modification of the dimension of the boundary operators such that the model produces asymptotic linear Regge trajectories. Both anomalous HW models considered here present mass percentage deviations of less than 3%, when compared with PDG data.

hep-ph↗

arXiv2024

Joule-Thomson expansion for quantum corrected AdS-Reissner-Nordstrom black holes in Kiselev spacetime

In this work we study the inversion temperature associated with the Joule-Thomson expansion from the thermodynamics of AdS-Reissner-Nördstrom black holes. We include quantum corrections in a cosmological fluid that can describe phantom dark matter or quintessence, both in a Kiselev scenario. The description of such physical systems involves numerical solutions and the results are presented as temperature-pressure plots for various values of the parameters of our model. We find non-zero minimum inversion temperatures as well as non-zero minimum pressures depending on the values of those parameters. Completing our study, we also find isenthalpic curves associated with black hole fixed mass processes.

gr-qc↗

arXiv2024

Bosonic and Fermionic Holographic Fluctuation and Dissipation at finite temperature and density

In this paper we investigate some general aspects of fluctuation and dissipation in the holographic scenario at zero and finite density. We model this situation with a probe string in a diagonal metric representing a black brane. The string stretches from the black brane to a probe brane thus simulating a stochastic driven particle. In this scenario, we compute the admittance, the diffusion coefficient, the correlation functions and the regularized mean square displacement, for bosons and fermions, all from the metric components. We check these calculations with the fluctuation-dissipation theorem. Further, we show that at finite temperature and density, the mean square displacement in the limit of short times reproduces the usual quadratic (ballistic) behavior, for bosons and fermions. For large times, we find ultraslow diffusive processes in various cases, except for bosons at zero chemical potential. We apply this general analysis in two different models: hyperscaling violation at finite temperature and a charged dilatonic AdS black hole, both for bosons and fermions. This is important because we found the fermionic diffusion in systems which allow the appearance of Fermi surfaces and Fermi liquids.

hep-th↗

arXiv2024

Anomalous and Linear Holographic Hard Wall Models for Glueballs and the Pomeron

In this work we propose improved holographic hard wall (HW) models by the inclusion of anomalous dimensions in the dual operators that describe glueballs inspired by the AdS/CFT correspondence. The anomalous dimensions come from well known semi-classical gauge/string duality analysis showing a dependence with the logarithm of spin $S$ of the boundary states. We show that these logarithm anomalous dimensions of the high spin operators combined with the usual HW model allow us to match the pomeron trajectory and give glueball masses which are better than that of the original HW and soft wall (SW) models in comparison with lattice data. We also build up other anomalous HW (AHW) models considering that the logarithm anomalous dimensions can be approximated by a truncated series of odd powers of the difference $\sqrt{S}-1/\sqrt{S}$. These models also fit the pomeron trajectory and produce good glueball masses. Then, we consider an anomalous dimension which is proportional to $\sqrt{S}$, providing reasonable results. Finally, we propose an asymptotic linear AHW model which effective dimensions for high spins operators are of the form $Δ=a\sqrt{S}+b$, where $a$ and $b$ are constants to be fixed by comparison with the soft pomeron trajectory. In this last model, the Regge trajectory is asymptotically linear even for very high spins ($J\sim 100$) matching the soft pomeron trajectory accurately and generates glueball masses with deviations with respect to the lattice data better than the original HW and SW models.

hep-ph↗

arXiv2024

Black branes in asymptotically Lifshitz spacetimes in $κ$-deformed Horndeski gravity

In this work we consider Horndesky gravity deformed by a parameter in its kinetic terms embedded in asymptotically Lifshitz spacetimes. We obtain black brane solutions in this geometry and study their thermodynamical properties. We show that the $κ$-deformation on the Horndeski kinetic terms allow for arbitrary values of the critical exponents characteristic of Lifshitz spacetimes. These solutions present local and global thermodynamical stabilites.

hep-th↗

arXiv2023

Comparison between holographic deformed AdS and soft wall models for fermions

We compare the holographic dressed soft wall and the exponentially deformed AdS models for spin 1/2 fermions. We present the dressed soft wall model and its analytical solutions for the left and right modes, and the corresponding spectra, also including modifications considering hyperfine spin-spin and meson cloud interactions, as well as anomalous dimensions. Then, we discuss the deformed AdS model for spin 1/2 fermions and present their effective Schrödinger equations for the left and right modes, for which only numerical solutions are available. Then, we consider a polynomial expansion of the effective potential of the deformed AdS model and show that in the quadratic approximation it leads to exact analytical solutions comparable with the dressed soft wall model and obtain the corresponding spectra for left and right modes. We show a numerical comparison of the mass spectra of spin 1/2 baryons for the dressed soft wall and the deformed AdS models. We present a detailed relation between the quadratic approximation of the deformed AdS and the dressed soft wall models for their spectra, wave functions and comments on the deep inelastic scattering on both models. We find that these two models are {\sl not} equivalent even in the quadratic approximation, but it is possible to relate their left and right modes for particular choices of their parameters.

hep-th↗

arXiv2022

A varying gravitational constant map in asymptotically AdS black hole thermodynamics

We propose a sequence of steps and a generic transformation for connecting common thermodynamic quantities considered in asymptotically anti-de Sitter black hole thermodynamics in the bulk and those that are appropriate for CFT thermodynamics in the boundary. We do this by constructing a "varying-$G$ map", where $G$ is the gravitational constant, and demonstrate its usefulness by considering various examples.

hep-th↗

arXiv2022

Shear viscosity from black holes in generalized scalar-tensor theories in arbitrary dimensions

In higher dimensions, we study Degenerate-Higher-Order-Scalar-Tensor theories and we derive solutions that resemble the Schwarzschild Anti-de Sitter black holes. We compute their thermodynamic quantities following the Wald formalism, satisfying the First Law of Thermodynamics and a higher dimensional Smarr relation. Constructing a Noether charge with a suitable choice of a space-like Killing vector, we obtain the shear viscosity of the non-gravitational dual field theory, where for a suitable choice of the couplings functions, the Kovtun-Son-Starinets bound is violated. These results are corroborated by the calculation of the Green's functions following the Kubo formalism.

hep-th↗

arXiv2022

Fermionic DIS from a deformed string/gauge correspondence model

From a deformed AdS$_5$ space, we used the string/gauge duality to study the deep inelastic scattering for unpolarized fermions with spin 1/2, considering the large Bjorken $x$ parameter regime. Here, we also took into account an anomalous dimension of an operator which represents fermions at the boundary. From this analysis, we compute the corresponding structure functions, which are dependent on $x$ and on the photon virtuality $q$. The results achieved are in agreement with the experimental data.

hep-ph↗

arXiv2022

Pion form factor from an AdS deformed background

We consider a bottom-up AdS/QCD model with a conformal exponential deformation $e^{k\,z^2}$ on a Lorentz invariant AdS background. In this model, we assume the conformal dimension associated with the operator that creates pions at the boundary as $Δ=3$. Regarding the infrared scale related to photon field $k_γ$, we analyze two cases: constant and depending on the transferred momentum $q$. In these two cases, we computed the electromagnetic pion form factor as well as the pion radius. We compare our results with experimental data as well as other theoretical (holographic and non-holographic) models. In particular, for the momentum-dependent infrared scale, we find good agreement with the available experimental data as well as non-holographic models.

hep-ph↗