arXiv subjects

Faizuddin Ahmed

Publications and source records attributed to Faizuddin Ahmed.

At least 127 records · Page 7Linked to original sources

arXiv2024

Impact of global monopole on heavy mesons in hot-dense medium

This research study is primarily focus on investigating how the topological effects influence the eigenvalue solutions in the presence of a hot-dense medium. To accomplish this, we employ the non-relativistic Schrödinger wave equation, taking into consideration both the quantum flux field and an interaction potential. Through this approach, we determine the energy eigenvalues and their corresponding wave functions using the Nikiforov-Uvarov method. Our findings indicate that when we consider both the topological effects and the magnetic flux, $Φ$, there is a noticeable reduction in the binding energy within the hot-dense medium. Additionally, we analyze the role of the baryonic potential in shaping the binding energy within the $(T, u_b)$ plane. Interestingly, it is evident that the influence of the baryonic potential becomes more pronounced as its values decrease

hep-th↗

arXiv2024

Scalar fields in Bonnor-Melvin Universe with potential: A study of dynamics of spin-0 particles-antiparticles

This research focus on the investigation of relativistic quantum dynamics of spin0 scalar particles/fields through the utilization of the Klein-Gordon (KG) equation within the framework of an electrovacuum space-time in the presence of an external scalar potential. Specifically, we focus on a cylindrical symmetric Bonnor-Melvin magnetic universe with a cosmological constant, where the magnetic field aligns along the symmetry axis direction. We derive the radial wave equation of the KG-equation by considering a Cornell-type scalar potential in the background of magnetic universe and successfully obtain an analytical eigenvalue solution for spin-0 quantum system. Notably, our findings reveal that both the energy spectrum and the corresponding radial wave function are significantly influenced by the presence of the cosmological constant, the topology parameter of the space-time geometry, which induces a deficit in the angular coordinates, and the potential parameters.

gr-qc↗

arXiv2024

Dynamics of Spin-0 (Particles-Antiparticles) in Bonnor-Melvin Cosmological Space-Time Using the Generalized Feshbach-Villars Transformation

In this paper, we employ the Generalized Feshbach-Villars transformation (GFVT) to investigate the relativistic quantum dynamics of spin-0 scalar particles within the backdrop of a magnetic universe characterized by the Bonnor-Melvin cosmological space-time, which exhibits a geometrical topology resulting in an angular deficit. We derive the radial equation of the Klein-Gordon equation using this FV representation and obtain analytical solutions utilizing special functions. Our analysis demonstrates that various parameters associated with the space-time geometry exert significant influence on the eigenvalue solutions within this novel representation. This research sheds light on the intricate dynamics of particles within the theoretical framework of quantum field theory in curved space-time.

gr-qc↗

arXiv2024

Quantum dynamics of spin-0 particles in a cosmological space-time

In this paper, our focus is on investigating the impact of cosmological constant on relativistic quantum systems comprising spin-0 scalar particles. Our analysis centers around the Klein-Gordon equation, and we obtain both approximate and exact analytical solutions for spin-0 particles of the quantum system. Afterwards, we explore quantum oscillator fields by considering the Klein-Gordon oscillator within the same space-time characterized by a cosmological constant. We obtain an approximate expression for the energy eigenvalue of the oscillator fields. In fact, the energy spectrum in both scenarios are examined and show the influences of the cosmological constant and geometry's topology. Our investigation is situated within the context of a magnetic universe-a four-dimensional cosmological space-time recognized as the Bonnor-Melvin universe

gr-qc↗

arXiv2024

Study of scalar particles through the Klein-Gordon equation under rainbow gravity effects in Bonnor-Melvin-Lambda space-time

In our investigation, we explore the quantum dynamics of charge-free scalar particles through the Klein-Gordon equation within the framework of rainbow gravity's, considering the Bonnor-Melvin-Lambda (BML) space-time background. The BML solution is characterized by the magnetic field strength along the axis of symmetry direction which is related with the cosmological constant $Λ$ and the topological parameter $α$ of the geometry. The behavior of charge-free scalar particles described by the Klein-Gordon equation is investigated, utilizing two sets of rainbow functions: (i) $f(χ)=\frac{(e^{β\,χ}-1)}{β\,χ}$,\, $h(χ)=1$ and (ii) $f(χ)=1$,\, $h(χ)=1+\frac{β\,χ}{2}$. Here $0 < \Big(χ=\frac{|E|}{E_p}\Big) \leq 1$ with $E$ represents the particle's energy, $E_p$ is the Planck's energy, and $β$ is the rainbow parameter. We obtain the approximate analytical solutions for the scalar particles and conduct a thorough analysis of the obtained results. Afterwards, we study the quantum dynamics of quantum oscillator fields within this BML space-time, employing the Klein-Gordon oscillator. Here also, we choose the same sets of rainbow functions and obtained approximate eigenvalue solution for the oscillator fields. Notably, we demonstrate that the relativistic approximate energy profiles of charge-free scalar particles and oscillator fields get influenced by the topology of the geometry and the cosmological constant. Furthermore, we show that the energy profiles of scalar particles get modifications by the rainbow parameter and the quantum oscillator fields by both the rainbow parameter and the frequency of oscillation

gr-qc↗

arXiv2024

Relativistic spin-0 Duffin-Kemmer-Petiau equation in Bonnor-Melvin-Lambda solution

In this paper, we conduct a comprehensive exploration of the relativistic quantum dynamics of spin-0 scalar particles, as described by the Duffin-Kemmer-Petiau (DKP) equation, within the framework of a magnetic space-time. Our focus is on the Bonnor-Melvin-Lambda (BML) solution, a four-dimensional magnetic universe characterized by a magnetic field that varies with axial distance. To initiate this investigation, we derive the radial equation using a suitable wave function ansatz and subsequently employ special functions to solve it. Furthermore, we extend our analysis to include Duffin-Kemmer-Petiau oscillator fields within the same BML space-time background. We derive the corresponding radial equation and solve it using special functions. Significantly, our results show that the geometry's topology and the cosmological constant (both are related with the magnetic field strength) influences the eigenvalue solution of spin-0 DKP fields and DKP-oscillator fields, leading to substantial modifications in the overall outcomes

gr-qc↗

arXiv2024

Gravitational lensing in a space-time with cosmic string within the Eddington-inspired Born-Infeld gravity

This study explores the deflection angle of photon rays or light-like geodesics within the framework of Eddington-inspired Born-Infeld (EiBI) gravity background space-time, taking into account the influence of cosmic strings. The primary focus lies in deriving the effective potential of the system applicable to both null and time-like geodesics, as well as determining the angle of deflection for light-like geodesics. Our analysis shows that the presence of cosmic strings induces modifications in these physical quantities, leading to shifts in their respective values.

gr-qc↗

arXiv2024

Non-relativistic quantum particles interacting with pseudoharmonic-type potential under flux field in a topological defect geometry

In this work, we investigate the quantum motions of non-relativistic particles interacting with a potential in the presence of the Aharonov-Bohm (AB) flux field within a topological defect geometry, for example, space-time with a distortion of a vertical line into a vertical spiral. We begin by deriving the radial Schrödinger wave equation, incorporating an anharmonic oscillator potential, which is a superposition of a harmonic oscillator and an inverse square potential, along with a constant term. The eigenvalue solution is obtained through the confluent Heun equation focusing on the ground state energy level and the radial wave function for the radial mode $n=1$ as an example and analyze the results. Subsequently, we use these results in molecular potential models, considering pseudoharmonic and shifted pseudoharmonic potentials. The derived eigenvalue solutions provide insights into the behavior of particles within these potentials. Expanding our exploration, we study the quantum system featuring only an inverse square potential in the presence of the quantum flux field in the same geometry background. Employing the same procedure, we determine the ground state energy level and the radial wave function. Notably, our findings reveal that the eigenvalue solutions are significantly influenced by the topological defect characterized by the parameter $β$, and the quantum flux field $Φ_{AB}$. This influence manifests as a shift in the energy spectrum, drawing parallels to the gravitational analog of the Aharonov-Bohm effect.

quant-ph↗

arXiv2024

Generalized Duffin-Kemmer-Petiau oscillator under Aharonov-Bohm flux in topological defects backgrounds

In this article, we study the generalized Duffin-Kemmer-Petiau (DKP) oscillator under the influence of quantum flux field in the topological defects produced by a cosmic string space-time and point-like global monopole. The generalized DKP oscillator will be investigated through a non-minimal substitution of the momentum operator $\vec{p} \to \left(\vec{p}+i\,M\,ω\,η^0\,f(r)\,\hat{r}\right)$ in the relativistic DKP equation. We solve this generalized DKP oscillator in a cosmic string space-time background and obtain the energy levels and wave function of the oscillator field using the parametric Nikiforov-Uvarov method. Afterwards, we solve the generalized DKP-oscillator in a point-like global monopole space-time and obtain the energy levels and wave functions following the same method. In fact, it is shown there that the energy eigenvalues are influenced by the topological defect of cosmic string and point-like global monopole and gets modified compared to flat space results, and breaks the degeneracy of the energy levels. Furthermore, we observe that the eigenvalue solutions depends on the quantum flux field that shows the gravitational analogue of the Aharonov-Bohm effect and also gives us a persistent currents

gr-qc↗

arXiv2024

Relativistic quantum oscillator under rainbow gravity's effects in traversable wormhole with disclination

In this paper, our principal objective is to investigate the impact of disclination and throat radius of a three-dimensional traversable wormhole on quantum oscillator fields. Specifically, we focus on Perry-Mann-type wormhole with disclination while also considering the influence of rainbow gravity's. We derive the radial equation of the relativistic Klein-Gordon oscillator within this wormhole background under the effects of gravity's rainbow and the analytical eigenvalue solution is obtained using the confluent Heun function. In fact, we show that the behavior of the oscillator fields is significantly influenced not only by the presence of disclination and the throat radius but also by the parameter of rainbow gravity's. We choose various such rainbow functions to present and analyze the eigenvalue solutions of the quantum oscillator fields.

gr-qc↗

arXiv2024

Quantum motions of scalar particles under rainbow gravity effects in spherical symmetrical Gödel-type metric with topological defects

In this research contribution, we explore the relativistic quantum dynamics of spin-0 scalar particles within a curved space-time background containing topological defects, while incorporating the effects of rainbow gravity. The Klein Gordon equation is solved in a spherically symmetrical Godel type space time, considering the presence of topological defects and the influence of rainbow gravity, described by the line element:

gr-qc↗

arXiv2023

Topologically Charged Rotating Wormhole

In this article, we present a stationary metric ansatz to describe a rotating traversable wormhole in the presence of the topological defect produced by a global monopole charge. This particular rotating space-time is referred to as the topologically charged rotating Schwarzschild-Klinkahmer wormhole. Our study involves the analysis of geodesic motion for test particles and photon rays in the context of this topologically charged rotating traversable wormhole. We aim to analyze the effects of global monopole charge and other parameters on the outcomes of this investigation. Additionally, we explore the matter-energy distribution within this rotating wormhole, considering it as a non-vacuum solution of Einstein's field equation. Notably, we demonstrate that the energy density of the matter content satisfies the criteria of the weak energy condition.

gr-qc↗

arXiv2023

A topologically charged four-dimensional wormhole and the energy conditions

In this research work, our primary focus revolves around the examination of a specific category of traversable wormholes known as topologically charged generalized Schwarzschild-Simpson-Visser-type wormhole, $ds^2=-\Big(1-\frac{2\,M}{\sqrt{x^2+b^2}}\Big)\,dt^2+\Big(1-\frac{2\,M}{\sqrt{x^2+b^2}}\Big)^{-1}\,\Big(\frac{dx^2}{α^2}\Big)+(x^2+a^2)\,(dθ^2+\sin^2 θ\,dϕ^2)$. This wormhole is uniquely defined by a pair of key parameters (length scales $a$ and $b$), together with the global monopole charge $α$. A noteworthy outcome of our investigation is the observation that the energy-momentum tensor associated with this wormhole complies with both the weak energy condition (WEC) and the null energy condition (NEC). Furthermore, incorporation of global monopole charge introduces a substantial influence on the curvature properties of wormhole space-time and various associated physical quantities derived from this geometry.

gr-qc↗

arXiv2023

Geodesics motion of test particles around Schwarzschild-Klinkhamer wormhole with topological defects and gravitational lensing

This study investigates the geodesic motion of test particles, both massless and massive, within a Schwarzschild-Klinkhamer (SK) wormhole space-time. We specifically consider the influence of cosmic strings on the system and analyze the effective potential, and observing that the presence of a cosmic string parameter alters it for null and time-like geodesics. Moreover, we calculate the deflection angle for null geodesics, and demonstrate that the cosmic string modifies this angle and induces a shift in the results. Additionally, we extend our investigation in this SK-wormhole space-time but with a global monopole. We explore the geodesic motion of test particles in this scenario and find that the effective potential is affected by the global monopole. Similarly, we determine the deflection angle for null geodesics and show that the global monopole parameter introduces modifications to this angle. Lastly, we present several known solutions for space-times involving cosmic strings and global monopoles within the framework of this SK-wormhole.

gr-qc↗

arXiv2023

Rotational and inverse square potential effects on harmonic oscillator confined by flux field in a space-time with screw dislocation

This research paper delves into the study of a non-relativistic quantum system, considering the interplay of non-inertial effects induced by a rotating frame and confinement by the Aharonov-Bohm (AB) flux field with potential in the backdrop of topological defects, specifically a screw dislocation. We first focus on the harmonic oscillator problem, incorporating an inverse-square repulsive potential. Notably, it becomes evident that the energy eigenvalues and wave functions are intricately influenced by multiple factors: the topological defect parameter $β$ (representing the screw dislocation), the presence of a rotating frame engaged in constant angular motion with speed $Ω$, and the external potential. Then we study the quantum behavior of non-relativistic particles, engaging in interactions governed by an inverse square potential, all while taking into account the effects of the rotating frame. In both scenarios, a significant observation is made: the quantum flux field's existence brings about a shift in the energy spectrum. This phenomenon bears a resemblance to the electromagnetic Aharonov-Bohm effect.

quant-ph↗

arXiv2023

A note on "The Klein-Gordon oscillator in (1+2)-dimensions Gürses space-time backgrounds (Ann. Phys. (N. Y.) 404 (2019) 1)"

We revisit and discuss the KG-oscillator in the $(1+2)$-dimensional Gürses space-time studied in (F. Ahmed, Ann. Phys. (N. Y.) 404 (2019) 1). The modified oscillator frequency {\it i.e.,} $\tildeω^{2}=(Ω^{2}\,E^{2}+η^{2})$ appeared in the eigenvalue equation is an energy-dependent parameter, and consequently, the results are accurately reported here. Moreover, we show some interesting spectroscopic features indulged within the very nature of Gürses space-time for the KG-Gürses oscillators.

gr-qc↗

arXiv2023

Geometrical Properties of a Point-like Global Monopole Spacetime

The aim of this paper is to study the geometric properties of the point-like global monopole (briefly, PGM) spacetime, which is a static and spherically symmetric solution of the Einstein's field equations. It has shown that PGM spacetime admits various types of pseudosymmetry structures, such as pseudosymmetry due to Weyl conformal curvature tensor, pseudosymmetry due to concircular curvature tensor, pseudosymmetry due to conharmonic curvature tensor, Ricci generalized conformal pseudo-symmetric due to projective curvature tensor, Ricci generalized projective pseudo-symmetric. Moreover, it has proved that PGM spacetime is $2$-quasi Einstein, generalized quasi-Einstein, Einstein manifold of degree $2$, and its Weyl conformal curvature $2$-forms are recurrent. The energy-momentum tensor of the PGM spacetime realizes several types of pseudosymmetry, and its Ricci tensor is compatible with Riemann curvature, Weyl conformal curvature, projective curvature, and conharmonic curvature and concircular curvature. Further, it has shown that PGM spacetime admits motion, curvature collineation, and Ricci collineation. Also, the notion of curvature inheritance (resp., curvature collineation) for the (1,3)-type curvature tensor is not equivalent to the notion of curvature inheritance (resp., curvature collineation) for the (0,4)-type curvature tensor as it has shown that such distinctive properties were possessed by PGM spacetime. Hence the notions of curvature inheritance defined by Duggal \cite{Duggal1992} and Shaikh and Datta \cite{ShaikhDatta2022} are not equivalent.

gr-qc↗

arXiv2023

Feshbach-Villars oscillator (FVO) in Kaluza-Klein Theory (KKT)

This research investigates the relativistic quantum dynamics of spin-0 scalar massive charged particles via the relativistic Feshbach-Villars oscillator in the background of the Kaluza-Klein Theory. We solve the Feshbach-Villars equation in the abckground of a cosmic string spec-time in the context of the Kaluza-Klein and presented the eigenvalue solution. Afterward, we rewrite this system in the case of the Feshbach-Villars quantum oscillator and obtain the eigenvalue analytically. Finally, we study the interaction of the Feshbach-Villars equation and oscillator in a cosmic dislocation in the Som-Raychaudhuri in the context of the Kaluza-Klein Theory and solve the wave equation analytically. We analyze the influence of topological defect in the quantification of energy and wave function of the Feshbach-Villars oscillator and with the external fields in the last one

hep-th↗