arXiv subjects

S. E. Ennadifi

Publications and source records attributed to S. E. Ennadifi.

10 recordsLinked to original sources

arXiv2026

Quantum Tunneling in the Everettian Multiverse

Quantum tunneling is analyzed within the Everettian interpretation, where decoherence generates distinct reflected and transmitted branches. The tunneling probability is obtained from relative branch weights via the Born rule without invoking collapse. Tunneling time $τ_T $ is reformulated as the branching duration $τ_T \sim N_B τ_B$, where$\ N_B $ is the number of environmental degrees of freedom and $τ_B$ is the decoherence time required to distinguish branches. Macroscopic tunneling in Josephson junctions is also analyzed.

quant-ph↗

arXiv2026

On Computational CUDA Studies of Black Hole Shadows

Combining high-performance CUDA numerical codes with the Hamilton--Jacobi formalism, we investigate the shadows properties of rotating charged Euler--Heisenberg black holes in the presence of global monopoles. Then, we discuss the associated energy emission rate by varying the involved black hole parameters. As a result, we show that both the shadow structure and the energy emission rate depend on the global monopole parameter, the electric charge, and the rotation parameter. However, we observe that the Euler--Heisenberg nonlinear parameter does not significantly affect either the shadow or the energy emission rate. In order to reconcile the present theoretical predictions with the shadow observations reported by the Event Horizon Telescope collaboration, we employ a CUDA-based computational approach to establish strict bounds on the GM parameter, the electric charge, and the rotation parameter.

physics.gen-ph↗

arXiv2025

Black Holes and Black Strings in M-theory on Calabi-Yau threefolds with four Kähler parameters

Combining toric geometry techniques and $\mathcal{N}=2$ supergravity formalisms, we study 5D black branes in the M-theory compactification on a four parameter Calabi-Yau threefold. First, we investigate 5D BPS and non-BPS black holes that are derived by wrapping M2-branes on non-holomorphic 2-cycles in such a toric Calabi-Yau manifold. Concretely, we provide the allowed electric charge regions of BPS and non-BPS black hole states that are obtained by surrounding M2-branes over appropriate 2-cycles. Then, we approach the black hole thermodynamic behavior by computing the entropy and the temperature. By evaluating the recombination factor, we examine the stability of such non-BPS black holes. Precisely, we find stable and unstable solutions depending on the allowed electric charge regions. After that, we study 5D black strings by wrapping M5-branes on non-holomorphic dual 4-cycles in the proposed toric Calabi-Yau manifold by focusing on the stability behaviors. In the allowed regions of the moduli space of the non-BPS stringy solutions, we find stable and unstable states depending on the magnetic charge values.

hep-th↗

arXiv2024

On Gravity Implication in the Wavefunction Collapse

Inspired by an ontic view of the wavefunction in quantum mechanics and motivated by the universal interaction of gravity, we discuss a possible gravity implication in the state collapse mechanism. Concretely, we investigate the stability of the spatial superposition of a massive quantum state under the gravity effect. In this context, we argue that the stability of the spatially superposed state depends on its gravitational self-energy originating from the effective mass density distribution through the spatially localized eigenstates. We reveal that the gravitational self-interaction between the different spacetime curvatures created by the eigenstate effective masses leads to the reduction of the superposed state to one of the possible localized states. Among others, we discuss such a gravity-driven state reduction. Then, we approach the corresponding collapse time and the induced effective electric current in the case of a charged state, as well as the possible detection aspects.

hep-th↗

arXiv2024

On Exchange-Correlation Energy in DFT Scenarios

Motivated by the considerable importance of material properties in modern condensed matter physics research, and using techniques of the $N_{e}$ -electron systems in terms of the electron density $n_{σe}\left( r\right) $ needed to obtain the ground-state energy $E_{e}$ in Density Functional Theory scenarios, we approach the Exchange-Correlation energy $ E_{xc}\left[ n_{σe}(r)\right] $ by considering the interelectronic position corrections $Δr_{x}^{\uparrow \uparrow ,\uparrow \downarrow }=λ_{x}\left\vert δr^{\uparrow \uparrow }-δr^{\uparrow \downarrow }\right\vert $ and $Δr_{c}^{e_{i}e_{j\neq i}}=λ_{c}\left\vert r-r^{\prime }\right\vert ^{-\left( N_{e}-1\right) ^{-1}}$ corresponding to the spin and the Coulomb correlation effects, respectively, through the electron-electron potential energy. Exploiting such corrections, we get approximate expressions for the exchange $E_{x}\left[ n_{σe} \right] $ and the correlation $E_{c}\left[ n_{σe}\right] $ functional energies which could be interpreted in terms of magnetic and electric dipole potential energies associated with the charge density $n_{σe}\left( r\right) $ described by inverse-square potential behaviors. Based on these arguments, we expect that such obtained Exchange-Correlation functional energy could be considered in the Local Density Approximation functional as an extension to frame such interelectronic effects.

cond-mat.mtrl-sci↗

arXiv2024

On 5D Black Brane Stabilities from M-theory on Three Parameter Calabi-Yau Threefolds

In this work, we reconsider the study of 5D black branes in M-theory compactifications by means of $\mathcal{N}=2$ supergravity formalism. Precisely, we provide a model relaying on a three parameter Calabi-Yau manifold in the $\mathbb{P}^{1}\times\mathbb{P}^{1}\times\mathbb{P}^{2}$ projective space factorization, referred to as economical model. First, we investigate the stability of 5D BPS and non-BPS black holes obtained from wrapped M2-branes on non-holomorphic two-cycles in such a Calabi-Yau manifold. Then, we approach the stability of 5D black strings derived from wrapped M5-branes on non-holomorphic four-cycles. Among others, we find various stable and unstable black brane solutions depending on the charge regions of the involved moduli space.

hep-th↗

arXiv2024

On Inflation and Axionic Dark Matter in a Scaled Gravity

Motivated by the modified gravity theories $F(R)\neq R$ and inflationary physics, we first propose and investigate an inflation model in a scaled gravity $F(R)=R\,+βR$, where $β$ is a dimensionless scaling parameter. The latter is also implemented in a particular potential $V(ϕ)=M^{4}\left[ 1-\cos \left( \frac{ϕ}μ\right)^{β}\right] $ being considered to drive the inflation via a parameter coupling scenario. Using the slow-roll approximations, the gravity scale parameter $β$ is approached with respect to the range of the associated computed cosmological observables $n_{s}$ and $r$ according to the recent Planck and BICEP/Keck data. Then, we discuss the axionic dark matter in the suggested gravity model by considering the case where the inflaton is taken to be identified with an axion-like field $ϕ=f_{a}θ$ with the decay constant $f_{a}=μ$. Referring to the known data, the underlying inflation scale $M$ is constrained to be much lower than the corresponding axion scale $M\ll f_{a}$.

hep-th↗

arXiv2024

Probing Quantum Entanglement from Quantum Correction to Newtonian Potential Energy

Inspired by string theory ideas, we probe quantum entanglement from the gravitational potential energy. Concretely, we reconsider the study of quantum corrections to the Newtonian potential energy by treating a massive two-particle system $m_{1}$ and $m_{2}$ with size dimensions $r_{1}$ ad $% r_{2}$ where the two particles separated by a distance $d$ are under only their mutual classical gravitational interaction $V_{r}\left( r_{1}\text{, }% r_{2}\right) $. Exploring such a size-dependent gravitational behavior and taking the limit $r_{1}$, $r_{2}\ll d$, we investigate the associated quantum biparticle state and express its evolution after an interaction time $τ$. Among others, we show that the two masses cannot be separable due to the induced gravitational entanglement in terms of the accumulated quantum phase $δϕ=δV_{g}τ/\hbar $. By analogy with the classical gravity, we derive the expression of the resulting extremely weak entanglement force from the corresponding gravitational entanglement energy. Then, we provide certain entanglement diagnostics.

quant-ph↗

arXiv2020

Dyonic Objects and Tensor Network Representation

Motivated by particle phyiscs results, we investigate certain dyonic solutions in arbitrary dimensions. Concretely, we study the stringy constructions of such objects from concrete compactifications. Then we elaborate their tensor network realizations using multistate particle formalism.

hep-th↗

arXiv2011

On Fermion Mass Hirerachies in MSSM-like Quiver Models with Stringy Corrections

Using instanton effects, we discuss the problem of fermion mass hierarchies in an MSSM-like Type IIA orientifolded model with U(3)xSp(1)xU(1)xU(1) gauge symmetry obtained from intersecting D6-branes. In the corresponding four-stack quiver, the different scales of the generated superpotential couplings offer a partial solution to fermion mass hierarchies. Using the known data with neutrino masses m_{v_τ}\lesssim 2 eV, we give the magnitudes of the relevant scales.

hep-th↗