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Abdelmalek Bouzenada

Publications and source records attributed to Abdelmalek Bouzenada.

At least 19 recordsLinked to original sources

Generalized Exact Fractional Quantum Information Model with Memory Effects

In this paper, we analyze quantum information measures in fractional quantum mechanics using the Riemann-Liouville derivative formalism adopted here. In this case, we initially reconsider the conventional definitions of Shannon entropy and Fisher information, subsequently extending them to fractional quantum systems described by nonlocal differential operator frameworks adopted. Within this generalized formulation, fractional expressions of Shannon entropy and Fisher information are constructed and their mathematical structures examined thoroughly. Also, the formalism is then applied to the quantum harmonic oscillator, yielding explicit analytical expressions derived as functions of the fractional parameter therein. The obtained results demonstrate that fractional derivatives alter the localization properties of probability densities and generate nontrivial variations in information content and sensitivity across system behavior. In this context, the fractional parameter plays a central role in controlling deviations from the standard quantum information measures framework. Also, the study establishes a consistent framework for describing information-theoretic properties of quantum systems governed by nonlocal dynamics.

quant-ph↗

Testing Catability and Coherent Superposition of $2\mathcal{D}$ Graphene Quantum system

We develop a theoretical framework for describing superposed coherent states in graphene quantum systems using the concept of catability as a phase-sensitive metric functional measure. In this case, the formalism quantifies interference stability and coherence structure via phase-dependent contributions of quantum superposition states. Catability is defined as a functional measure sensitive to relative phase variations within coherent state combinations, serving as a diagnostic tool for quantum interference effects in graphene-based systems. Also, the formulation is extended using Lie algebra techniques, where the underlying symmetry structure of graphene quantum states is represented through operator algebras governing state transformations in quantum space. In this context, to describe nonlocal propagation and phase-resolved dynamics, a Green function approach is incorporated, enabling systematic treatment of quantum correlations in a spatially extended structures framework. A unified framework is constructed by combining Lie algebraic symmetry analysis with Green function propagation theory, yielding a consistent description of phase-sensitive catability in complex graphene quantum configurations within the framework approach. Results provide a structured route for testing coherence, interference stability, and quantum state control in low-dimensional quantum materials systems.

quant-ph↗

Generalized Catability of Relativistic Quantum States Measurement in a Unified Lie-Algebraic Foldy-Wouthuysen (FW) Framework

In this work, a unified Lie-algebraic formulation of catability is constructed for relativistic quantum systems with arbitrary spin within this framework. In this case, the analysis starts with constructing catability as a quantitative measure for superposed coherent states, where coherence structure and quantum interference properties are studied using algebraic representations in this framework. Also, a generalized Foldy-Wouthuysen transformation is formulated within a Lie algebraic framework, delivering a systematic procedure for block-diagonalization of relativistic Hamiltonians and separation of positive- and negative-energy components in this framework. Within this formalism, a phase-sensitive catability operator is introduced to study phase correlations and coherence effects in the relativistic quantum dynamics framework. The approach is applied to Dirac spin-$1/2$ particles, where relativistic fermionic catability is analyzed in relation to spinorial structures and symmetry generators framework. The formalism is extended through a unified geometric and Lie-algebraic treatment, establishing a consistent description of catability in a relativistic quantum mechanics framework. In this context, the generalized framework is constructed for arbitrary spin-$s$ fields, enabling investigation of higher-spin relativistic quantum states within the same algebraic structure framework. In this context, the obtained results show a generalized theoretical platform for investigating relativistic quantum coherence, superposition effects, and algebraic symmetries in the framework of fermionic and bosonic systems.

quant-ph↗

Hairy Kiselev black hole with quintessential matter: themodynamic properties, sparsity of Hawking radiation, and greybody factors

In this work, we investigate the thermodynamic properties, Hawking-radiation sparsity, and greybody-factor bounds of a hairy Kiselev black hole surrounded by a quintessential fluid. The spacetime geometry contains, in addition to the Schwarzschild mass term, a quintessence contribution controlled by the intensity parameter $N$ and the state parameter $ω_q$, an exponential hair correction governed by the coupling $α$ and the primary hair scale $\ell$, and a cosmological constant $Λ$. We first examined the horizon structure and derived the black hole mass from the horizon condition. The Hawking temperature, heat capacity, and Gibbs free energy were then analyzed in order to identify the influence of the hair and surrounding-field parameters on local and global thermodynamic behavior. The results show that the exponential hair mainly affects the small-horizon regime, while the quintessential sector and the cosmological constant produce significant changes in the large-scale behavior of the black hole. In particular, the heat capacity exhibits divergences associated with second-order phase transitions, and the Gibbs free energy reveals the possibility of competing thermodynamic branches. We also analyzed the sparsity of Hawking radiation and showed that the emitted flux is highly intermittent rather than continuous. The sparsity parameter is controlled by the combination of the Hawking temperature, the effective emitting area, and the greybody factors. Finally, we studied massless scalar perturbations in this background by reducing the Klein-Gordon equation to a radial equation with an effective potential.

gr-qc↗

ModMax-black hole surrounded by cloud of strings in Bumblebee gravity

In this article, we investigate the optical, thermodynamic, and scattering properties of a ModMax black hole surrounded by a cloud of strings within the framework of Einstein-bumblebee gravity. We then analyze in detail the thermodynamic properties of this black hole, including the Hawking temperature, entropy, and other relevant thermodynamic quantities, and examine the outcomes. Furthermore, we study the greybody factors (GFs) associated with the emission of various perturbative fields propagating in this black hole background. In particular, we consider spin-0 scalar fields, spin-1 electromagnetic fields, and spin-2 graviton fields, and evaluate the corresponding absorption probabilities and energy emission rates. Our analysis demonstrates how the optical features, thermodynamics and GFs depend on the underlying parameters of the system, such as the Lorentz symmetry violation parameter, the cloud of strings parameter, the ModMax parameter, the electric charge, and the black hole mass, thereby providing a comprehensive understanding of the physical effects of these parameters on the radiation and scattering processes around the black hole.

gr-qc↗

Testing $(q)$-Deformed Dunkl-Fokker-Planck Equation Algebra with Supersymmetry (SUSY) and Foldy-Wouthuysen (FW) Measurement

In this study, a relativistic formulation of the $(q)$-deformed Dunkl-Fokker-Planck equation in $(1+1)$-dimensions is constructed within the reflection-deformed quantum framework. In this case, the formalism includes $(q)$-deformed Dunkl operators and reflection symmetry to build a generalized dynamical structure for a relativistic quantum systems framework. Moreover, the corresponding $(q)$-Wigner-Dunkl supersymmetric configuration is established via the construction of deformed ladder operators and supersymmetric algebraic relations, yielding a consistent spectral representation of the model within the algebraic framework. The analysis extends to the harmonic oscillator with centrifugal interaction, where exact algebraic solutions, similarity reduction techniques, and closed energy spectra are obtained analytically in detail. The role of the deformation parameter and reflection operator on spectral properties and wavefunction structure is examined systematically in detail. A generalized Foldy-Wouthuysen (FW) transformation is introduced within the deformed Dunkl framework to achieve relativistic decoupling of positive- and negative-energy sectors within the present theoretical formulation. In this case, this approach yields an effective reduced Hamiltonian, including higher-order relativistic and deformation-induced terms. Also, the associated Dunkl-Fokker-Planck dynamics generated through high-order FW reduction are examined in detail for reflection-deformed relativistic quantum systems. In this context, results obtained here yield a unified algebraic and relativistic description of $(q)$-deformed Dunkl structures and construct a consistent framework for investigating supersymmetric and relativistic properties in reflection-symmetric quantum models in general.

hep-th↗

Analytical Solutions of One-Dimensional ($1\mathcal{D}$) Potentials for Spin-0 Particles via the Feshbach-Villars Formalism

We present a unified analytical and numerical study of the one-dimensional Feshbach--Villars (FV) equation for spin-0 particles in the presence of several representative external potentials. Starting from the FV formulation of the Klein--Gordon equation, we derive the corresponding one-dimensional master equation and analyse its solutions for Coulomb, power-exponential, Cornell, Pöschl--Teller, and Woods--Saxon interactions. For the singular Coulomb and Cornell cases, a Loudon-type cutoff regularisation is implemented on the full line, allowing a mathematically controlled treatment of the origin and an explicit classification of the states by parity. The Coulomb problem exhibits the expected near-degenerate even--odd structure in the cutoff limit, while the Cornell potential combines short-distance Coulomb behaviour with long-distance confinement and produces a finite set of bound states for fixed parameters. The power-exponential potential with $p=1$ is reduced to a Whittaker-type equation and yields an intrinsically relativistic spectrum with no standard Schrödinger bound-state limit in the parameter regime considered. For the smooth short-range Pöschl--Teller and Woods-Saxon potentials, the FV formalism reveals, respectively, the effects of definite parity and spatial asymmetry on the spectrum, wave functions, and particle--antiparticle mixing. In all cases, we reconstruct the full FV spinor, analyse the associated charge density, and compare the relativistic behaviour with the corresponding non-relativistic expectations whenever such a limit exists. The results provide a coherent set of analytical and numerical benchmarks for relativistic scalar bound states in one dimension.

quant-ph↗

Phase Transitions, Geodesic Structure, and Thermodynamic Properties Measurement of Einstein-Maxwell-Power Yang-Mills Black Hole Models

In this work, we test the geometrical structure and thermodynamic properties of the Einstein-Maxwell-Power-Yang-Mills black hole (BH) models, which constitute a nonlinear generalization of the standard Einstein-Yang-Mills theory through the inclusion of a power-law Yang-Mills invariant. Also, we begin by analyzing the spacetime geometry via the metric function $f(r)$ and examine the modifications induced by the electromagnetic charge and nonlinear Yang-Mills parameter on the horizon structure, causal structure, and gravitational potential. Subsequently, the dynamics of photons and massive particles are explored through the study of null and timelike geodesics, allowing the determination of the effective potential, photon sphere radius, and associated BH shadow. Also, the stability of circular photon orbits is quantified using the Lyapunov exponent, which characterizes the timescale of orbital instability and provides a direct link to observable photon ring features. For massive particles, the innermost stable circular orbit (ISCO) is calculated, illustrating the influence of BH parameters on the dynamics of accretion disks. From the thermodynamic viewpoint, we compute the principal thermodynamic quantities, including the BH mass, Hawking temperature, Bekenstein-Hawking entropy, heat capacity, and Gibbs free energy, to assess both local and global stability of the system. The divergence of the heat capacity signals the occurrence of second-order phase transitions, whereas the Gibbs free energy analysis identifies possible first-order phase transitions between distinct thermodynamic configurations. In this context, our results demonstrate that the nonlinear Yang-Mills parameter strongly affects the spacetime geometry, particle dynamics, and thermodynamic phase structure, shifting the location of stability regions and critical points associated with phase transitions.

gr-qc↗

Quantum Oppenheimer-Snyder Black Holes with a Cloud of Strings Surrounded by Perfect Fluid Dark Matter

In this study, we examine quantum Oppenheimer-Snyder black holes (BHs) embedded within a cloud of strings and immersed in perfect fluid dark matter. Also, beginning with the underlying spacetime geometry, we determine how quantum corrections, string cloud contributions, and dark matter effects alter the geometrical structure and physical characteristics of the BH. Also, the optical behavior is investigated via a systematic analysis of the photon sphere and the associated BH shadow, emphasizing possible observational features capable of differentiating this configuration from classical models. We also analyze the motion of test particles, focusing on how surrounding matter components affect trajectories, stability conditions, and effective potentials. Scalar field perturbations are considered to investigate the BH response to external excitations and to extract information regarding its dynamical properties. In this case, the thermodynamic behavior of the system is studied, including the role of string clouds and dark matter in modifying BH thermodynamic quantities. Also, the obtained results present a unified description of the combined effects of quantum corrections, nonstandard matter sources, and BH physics, with potential relevance for both observational constraints and theoretical modeling of compact objects.

gr-qc↗

Dymnikova Black Hole Immersed in Perfect Fluid Dark Matter and a Cloud of Strings: Hawking Temperature, Dynamics and QPOs Analysis

The Dymnikova black hole represents a regular spacetime solution interpolating between a de Sitter core and an asymptotically Schwarzschild geometry. In this work, we investigate a generalized Dymnikova black hole surrounded by perfect fluid dark matter (PFDM) and immersed in a cloud of strings (CS). We analyze how these additional matter sources modify the thermodynamic, optical, and dynamical properties of the spacetime. We derive the Hawking temperature and specific heat capacity and examine the thermal stability and phase structure of the black hole. The results reveal non-monotonic temperature behavior and parameter-dependent phase transitions. We further study photon dynamics, including the photon sphere and black hole shadow, and show that both PFDM and string cloud parameters significantly affect the shadow radius and strong-field structure. Additionally, we investigate the motion of massive test particles, circular orbits, and stability conditions. The corresponding effective potentials, specific energy, and angular momentum are analyzed. Finally, we explore quasi-periodic oscillations (QPOs) by computing the fundamental epicyclic frequencies and discuss how the model parameters encode observable astrophysical signatures.

gr-qc↗

Relativistic Dynamics and Bondi-Hoyle-Lyttleton Accretion onto Rotating Embedded Black Hole Models

In this paper, we examine the motion of test particles and relativistic accretion mechanisms within the spacetime of a rotating and embedded BH. In this case, the geometric properties of the metric and their dynamical consequences for particle trajectories are systematically studied, with a specific focus on circular orbits together with their existence criteria and stability constraints. Also, the effective potential and the corresponding effective force are constructed to quantify the influence of rotation and embedding parameters on the attractive and repulsive sectors of the gravitational interaction. Closed-form expressions for orbital frequencies as measured by a distant observer are derived, enabling a quantitative analysis of relativistic precession phenomena, including periastron advance and Lense-Thirring precession. Furthermore, we conduct general-relativistic hydrodynamic simulations of BHL accretion onto rotating embedded BHs. In addition, within the framework of the BHL accretion mechanism, the numerical solution of the GRH equations shows that the embedding parameter αsystematically modifies the morphology of the shock cone formed around embedded BHs compared to the Kerr model. In particular, a wider opening angle of the cone is produced, the compression of matter in the post-shock region is weakened, and the dynamical variability of the flow is enhanced. The time-dependent mass accretion rate exhibits increasing oscillation amplitudes and long-term variations with increasing α, while these amplitudes are found to be suppressed by the frame-dragging effect associated with the BH spin parameter. At the same time, increasing values of $α$ lead to a strengthening of the QPO frequencies formed around embedded BHs in the LFQPO regime, enhancing their observability and increasing the likelihood of detecting commensurate frequency ratios such as 3:2.

astro-ph.HE↗

Non-exotic traversable wormholes with strong deflection angle in King and Dekel-Zhao dark matter halos under f(R,Lm) gravity

In this article, we investigate asymptotically flat non-exotic traversable wormhole geometries within the King and Dekel-Zhao dark matter halos in the framework of $f(R, L_m)$ gravity. Two functional forms of the theory are considered: Model-I: $f(R, L_m)=(R/2) + L_m^α$ and Model-II: $f(R, L_m)=(R/2) + (1 + λR)L_m$. For both models, wormhole solutions are obtained and analyzed using the King and Dekel-Zhao dark matter density profiles, allowing us to explore how the underlying matter distribution influences the wormhole structures. The energy conditions are examined to verify the feasibility of sustaining the wormhole geometries with non-exotic matter, while embedding surfaces, proper radial distance, and total gravitational energy are studied to illustrate the wormhole's physical viability and traversability. Moreover, we test the strong deflection angle and its implications for gravitational lensing and show possible observational signatures of such wormhole configurations. Our results indicate that within $f(R, L_m)$ gravity, and for appropriate parameter choices, dark matter environments can sustain physically consistent non-exotic traversable wormhole geometries with distinct gravitational lensing signatures, providing new insights into the interplay between modified gravity, dark matter, and astrophysical observations.

gr-qc↗

Relativistic accretion process onto rotating black holes in Einstein-Euler-Heisenberg nonlinear electrodynamic gravity

In this study, we uncover the accretion dynamics and oscillatory behavior around rotating black holes within the EEH nonlinear electrodynamic framework by analyzing both the motion of test particles and numerically solving the general relativistic hydrodynamic equations. Using EEH geometry, we compute the structure of circular motion, the effective potential and force, and we evaluate the orbital, radial, and vertical epicyclic frequencies together with the Lense-Thirring and periastron precession rates. Our calculations show that, compared to the Kerr model, the charge parameter $Q$ and the spin parameter $a$ significantly modify the strong gravitational field and shift the characteristic frequencies. We then model the dynamical structure formed by matter accreting toward the EEH black hole through the BHL mechanism, finding that the parameter $Q$ increases the amount of infalling matter and strengthens shock-cone instabilities near the horizon, while farther from the black hole it suppresses accretion and reduces turbulence. Time-series analysis of the accretion rate reveals robust QPOs, whose low-frequency components arise from the precession of the shock cone, while high-frequency components appear as a consequence of strong-field instabilities modified by $Q$ and $a$. A systematic parameter-space exploration identifies the regions where EEH corrections maximize QPO activity, indicating that nonlinear electrodynamics can leave observable imprints on accretion flows and may be testable with QPO and horizon-scale observations.

gr-qc↗

Magnetized particle motion and accretion process with shock cone morphology around a decoupled hairy black holes

Relativistic accretion onto compact objects such as black holes and neutron stars is one of the most efficient known mechanisms for converting gravitational potential energy into radiation. In the case of rapidly spinning black holes, up to $40\%$ of the rest-mass energy of accreting matter can be released, far exceeding the efficiency of nuclear fusion. In this work, we investigate magnetized particle motion and relativistic accretion processes around a decoupled hairy black hole via extended geometric deformation. The developed geometry involves two hairy parameters that preserve the horizon structure with the additional feature of the fulfillment of weak energy conditions outside the event horizon. We provide the foundation with necessary formalism for magnetized particle motion around a decoupled black hole. The effective potential and innermost stable circular orbits are then derived, which demonstrate a significant reduction of the radius of the latter quantity under the hairy parameters for the magnetized particle. Afterwards, we obtain exact analytical expressions for radial velocity profiles, mass accretion rates, and a few others which reveal improved energy efficiency and emissivity as compared to the standard black hole. Furthermore, the decoupling parameter shows strong influence on oscillations, accretion presenting fantastic agreement between analytical predictions and numerical simulations, and thus offering noticeable observational signatures for future gravitational wave and X-ray astronomy.

astro-ph.HE↗

Yukawa-Casimir wormholes within Einstein-Cartan gravity framework

The Einstein-Cartan (EC) theory of gravity provides a natural extension of general relativity by incorporating spacetime torsion to account for the intrinsic spin of matter. In this work, we investigate Yukawa-Casimir traversable wormholes supported by three distinct Yukawa-Casimir energy density profiles within the framework of EC gravity. The resulting shape functions are shown to satisfy all the fundamental requirements for traversable wormhole geometries. Our analysis reveals that the presence of exotic matter is unavoidable in sustaining these wormholes, and we quantify its total amount through the volume integral quantifier. Furthermore, the equilibrium of the wormhole configurations is established by examining the Tolman-Oppenheimer-Volkoff equation. To enhance the physical relevance of the present work, we study several key features of the wormholes, including the embedding surface, proper radial distance, tidal forces, and total gravitational energy. In addition, we analyze the optical properties of wormholes by examining both the shadow and the strong deflection angle. All the findings collectively demonstrate the physical plausibility of Yukawa-Casimir traversable wormholes within the EC gravity framework.

gr-qc↗

Static AdS Black Holes Surrounded by Strings and Quintessence-like Field within Rastall Gravity Framework

In this work, we tested the physical properties of Rastall black holes in the presence of string clouds and quintessence. The modified spacetime geometry arising from the Rastall framework is first established, providing the basis for analyzing the geodesic structure. We study null geodesics in detail, testing photon trajectories, the conditions for photon spheres, BH shadows, the associated effective radial force, and the topological features of photon rings. Also, the analysis is further tested to timelike geodesics, where we investigate the motion of massive particles and determine the innermost stable circular orbits. In this case, we discuss the thermodynamic behavior of the system, show the effects of Rastall gravity, strings, and quintessence on the BHs stability and thermal characteristics. In this context, our results improve and show of how modifications to general relativity and surrounding matter distributions influence both the dynamical and thermodynamical aspects of BHs.

gr-qc↗

AdS Black Hole Solution with a Dark Matter Halo Surrounded by a Cloud of Strings

We derive and analyze a Schwarzschild-like Anti-de Sitter (AdS) black hole (BH) obtained as a static, spherically symmetric solution of Einstein's equations sourced by a cloud of strings (CoS) and a dark matter (DM) halo modeled by a Dehnen-type density profile. We first study the geodesic motion of massless and massive test particles, emphasizing how the CoS parameter $α$ and the DM halo parameters $(ρ_s, r_s)$ influence photon spheres, circular orbits, the BH shadow, and the innermost stable circular orbit (ISCO). We then examine scalar perturbations via the effective potential and the associated quasinormal-mode (QNM) spectra, showing how $α$ and $(ρ_s, r_s)$ deform oscillation frequencies and damping rates, thereby affecting stability diagnostics. Furthermore, we investigate the thermodynamics in the extended phase space, deriving the Hawking temperature, equation of state, Gibbs free energy, and specific heat capacity, and establishing a consistent first law and Smarr relation with natural work terms for $α$ and $(ρ_s, r_s)$. We find that the interplay between the CoS and the DM halo produces quantitative and sometimes qualitative changes in both dynamical and thermodynamical properties, including shifts of the Hawking--Page transition and heat-capacity divergences, thus reshaping the phase structure of Schwarzschild--AdS BHs.

gr-qc↗

Thermodynamics and Joule-Thomson Expansion for Schwarzschild-AdS Black Holes with Cloud of Strings and Quintessential-like Fluid

In this study, we explore the thermodynamic properties of a Schwarzschild black hole (BH) embedded in an anti-de Sitter (AdS) background, which is further coupled with a cloud of strings and surrounded by a quintessence-like fluid. Beginning with the formulation of BH mass in terms of the event horizon radius, we incorporate the concept of pressure as related to the AdS curvature radius within the framework of extended phase space thermodynamics. Using this setup, we derive key thermodynamic quantities, including the Gibbs free energy and internal energy, to characterize the energetic behavior of the black hole system. To assess the stability of the black hole, we compute the specific heat capacity and analyze how it is influenced by external parameters, such as the string cloud and the quintessence-like fluid. These geometric and matter fields are shown to significantly modify the thermal response of the BH. Furthermore, we examine the inversion temperature associated with the black hole and highlight its distinction from the standard Hawking temperature, providing deeper insight into the phase structure. Additionally, we investigate the Joule-Thomson expansion process and demonstrate how the aforementioned parameters affect this thermodynamic phenomenon, showing important aspects of BH cooling and heating behavior in an extended thermodynamic context.

gr-qc↗