arXiv subjects

Babur M. Mirza

Publications and source records attributed to Babur M. Mirza.

17 recordsLinked to original sources

arXiv2023

Phase Space Analysis of Fluorine-Oxygen-Nitrogen Network and Energy Generation in Flourine-Oxygen Reaction

Reaction network of fluorine-18, oxygen-15 and nitrogen-15 is considered for its temperature dependent energy output. The main reactions for generation and annihilation of oxygen and fluorine are coupled in the reaction equations while nitrogen is produced as a decay product. We find that the governing set of equations for F18(p, alpha)O15 process in the phase diagram exhibit a predominance of the direct reaction rather than the reverse reaction consuming O15. The time-scale determined by the exact solution of this system yields relatively short time-scale conversion of fluorine into oxygen indicating an energy generation of 2.8MeV per reaction. The temperature dependence shows that the effective reaction occurs at temperature about 0.04GK or above.

physics.gen-ph↗

arXiv2020

Can Orbital Clustering of KBOs in the Ecliptic be due to the Solar Toroidal Field Generated Spacetime Dragging?

The Kuiper belt objects (KBOs) exhibit an orbital clustering of the outer planets lying at perihelion distances larger than Neptune and semimajor axes greater than 150 AU from the Sun. This implies a hitherto unknown dynamical mechanism to counter randomizing of the orbital elements caused by the giant solar system planets. Using the toroidal field induced frame-dragging we deduce here the observed range of the Kuiper belt region, the semi-major axis of Sedna like objects in the Kuiper belt, as well as the orbital clustering of the KBOs in the ecliptic, without assuming dynamical effects induced by trans-Neptunian-objects (TNOs). We also calculate the orbital precession rates for the inner planets and show their correspondence, within the range of observational accuracy, with recent planetary ephemerides.

astro-ph.HE↗

arXiv2019

The Flyby Anomaly and the Gravitational-Magnetic Field Induced Frame-Dragging Effect around the Earth

The anomalous energy difference observed during the Earth flybys is modelled here as a dynamical effect resulting from the coupling of the gravitational and the magnetic fields of the Earth. The theoretical analysis shows that general relativistic frame-dragging can become modified under the Earth's magnetic field by orders of magnitude. For twelve flyby cases, including the null results reported in some recent flybys, the predicted velocities correspond to the observed velocities within the observational error. The gravito-magnetic effect is also shown to account for the linear distance relation, time-variation of the anomalous energy, and the reduction in the anomalous velocity for high altitude flybys near the Earth.

astro-ph.HE↗

arXiv2018

Can accelerated expansion of the universe be due to spacetime vorticity?

We present here a general relativistic mechanism for accelerated cosmic expansion and the Hubble's constant. It is shown that spacetime vorticity coupled to the magnetic field density in galaxies causes the galaxies to recede from one another at a rate equal to the Hubble's constant. We therefore predict an oscillatory universe, with zero curvature, without assuming violation of Newtonian gravity at large distances or invoking dark energy/dark matter hypotheses. The value of the Hubble's constant, along with the scale of expansion, as well as the high isotropy of CMB radiation are deduced from the model.

astro-ph.CO↗

arXiv2017

Travelling Magnetic Waves due to Plasma Surrounding a Slow Rotating Compact Gravitational Source

The magnetic field due to an axially symmetric, hot and highly conducting plasma, taken as an ideal magnetohydrodynamic fluid, surrounding a slow rotating compact gravitational object is studied within the context of Einstein-Maxwell field equations. It is assumed that whereas the plasma is effected by the background spacetime it does not effect the spacetime itself. The Einstein-Maxwell equations are then solved for the magnetic field in a comoving frame with the background spacetime described by the slow rotating Kerr black hole spacetime. It is found that the solutions are magnetic waves travelling along the azimuthal angle with velocity equal to the angular velocity of a free falling intertial frame. These general solutions, when applied to various particular cases of physical interest, show that for a fixed value of the azimuthal angle the magnetic field is completely induced by the dragging of the background spacetime.

gr-qc↗

arXiv2017

Transmission time and resonant tunneling through barriers using localized quantum density soliton waves

In this paper, the interaction and transmission time of quantum density solitons waves representing particles passing through finite barrier potentials is investigated. Using the conservation of energy and of quantum density, it is first demonstrated that these waves have finite de Broglie wavelength and represent particles in quantum theory. The passage of the quantum density solitons (particles) through barriers of finite energies is then shown to lead to the phenomena of resonant tunneling and, in Josephson-like configurations, to the quantization of magnetic flux. A precise general measure for barrier tunneling time is derived which is found to give a new interpretation of the quantum indeterminacy principles.

quant-ph↗

arXiv2017

On Wave Function Representation of Particles as Shock Wave Discontinuities

In quantum theory particles are represented as wave packets. Shock wave analysis of quantum equations of motion shows that wave function representation in general and wave packet description in particular contains discontinuities due to a non-zero quantum force. The quantum force causes wave packet dispersion which results in the intersection of characteristic curves developing a shock discontinuity. Since quantum force vanishes for localized quantum density waves [1], it is thus established that localized quantum density waves form the only class of wave function representation of particles in quantum theory without shock wave discontinuities.

quant-ph↗

arXiv2015

Condensate Nuclei and Magnetic Polarity Reversals in the Sun and Solar-type Stars

Magnetic field generation in the Sun and solar-type stars is modeled here based on the formation of magnetically polarized condensates (B. M. Mirza, Mod. Phys. Lett. B 28 (2014) 1450148) under the high density and pressure conditions. The correct orders of magnitude for the time period and the energy loss in a solar cycle are deduced, as well as the enhancement in the energy emission observed during solar cycles. It is shown that this feedback magnetic field along with differential rotation is sufficient to generate the toroidal magnetic field in the solar exterior. The model is useful in determining magnetic polarity reversals, energy generation, and reversal times, in solar-type stars.

physics.gen-ph↗

arXiv2012

Soliton Formation in Neutral Ion Gases: Exact Analysis

It is shown here that in neutral ion gases the thermal energy transport can occur in the form of new types of thermal soliton waves. The solitons can form under a vanishing net heating function, and for a quadratic net heating. It is predicted that these solitons play an important role in a diversity of terrestrial and astrophysical phenomena. We claim that the reported soliton waves can be observed under ordinary laboratory conditions.

nlin.PS↗

arXiv2009

Counterpropagating Wavepacket Solutions of the Time-Dependent Schroedinger Equation for a Decaying Potential Field

We investigate wavepacket solutions for time-dependent Schoedinger equation in the presence of an exponentially decaying potential. Assuming for travelling wave solutions the phase to be a linear combination of the space and time coordinates, we obtain two distinct wavepacket solutions for the Schroedinger equation. The wavepackets counterpropagate in space at a constant velocity without any distortion or spreading thus retain their initial form at arbitrarily large distances.

quant-ph↗

arXiv2008

Does Charge Contribute to the Frame Dragging of Spacetime?

Electrically charged systems bound by a strong gravitational force can sustain a huge amount of electric charge (up to 10^20C) against Coulomb repulsion. General relativistically such systems form a stable hydrostatic configuration both in the non-rotating and rotating cases. Here we study the effects of electric charge (electric energy density) on the spacetime outside a rotating electrically charged system bound by a strong gravitational force. In particular we investigate the effect of charge density on frame-dragging of spacetime in the exterior region. Using the coupled Einstein-Maxwell equations it is found that in the slow rotation approximation charge accumulations not only acts like an additional mass, thus modifying the spherically symmetric part of the spacetime, the electric charge also contributes directly to the dragging of spacetime. A modified Lense-Thirring formula for the spacetime frame dragging frequency is obtained.

gr-qc↗

arXiv2008

Symmetry Reduction of Lane-Emden Equation for Polytropes

We describe an ansatz for symmetry reduction of the Lane-Emden equation for an arbitrary polytropic index n, admitting only one symmetry generator. For the reduced first order differential equation it is found that standard reduction procedure do not admit any non-trivial Lie point symmetry. However some special solutions for the differential equation are obtained.

math-ph↗

arXiv2007

Chaotic Accretion in a Non-Stationary Electromagnetic Field of a Slowly Rotating Compact Star

We investigate charge accretion in vicinity of a slowly rotating compact star with a non-stationary electromagnetic field. Exact solutions to the general relativistic Maxwell equations are obtained for a star formed of a highly degenerate plasma with a gravitational field given by the linearized Kerr metric. These solutions are used to formulate and then to study numerically the equations of motion for a charged particle in star's vicinity using the gravitoelectromagnetic force law. The analysis shows that close to the star charge accretion does not always remain ordered. It is found that the magnetic field plays the dominant role in the onset of chaos near the star's surface.

astro-ph↗

arXiv2005

Gravitomagnetic Effects on Collective Plasma Oscillations in Compact Stars

The effects of gravitomagnetic force on plasma oscillations are investigated using the kinetic theory of homogeneous electrically neutral plasma in the absence of external electric or magnetic field. The random phase assumption is employed neglecting the thermal motion of the electrons with respect to a fixed ion background. It is found that the gravitomagnetic force reduces the characteristic frequency of the plasma thus enhancing the refractive index of the medium. The estimates for the predicted effects are given for a typical white dwarf, pulsar, and neutron star.

astro-ph↗

arXiv2005

Plasma Frequency Shift Due to a Slowly Rotating Compact Star

We investigate the effects of a slowly rotating compact gravitational source on electron oscillations in a homogeneous electrically neutral plasma in the absence of an external electric or magnetic field. Neglecting the random thermal motion of the electrons we assume the gravitoelectromagnetic approximation to the general theory of relativity for the gravitational field. It is shown that there is a shift in the plasma frequency and hence in the dielectric constant of the plasma due to the gravitomagnetic force. We also give estimates for the difference in the frequency of radially transmitted electromagnetic signals for typical compact star candidates.

astro-ph↗

arXiv2004

Charged Particle Dynamics in the Field of a Slowly Rotating Compact Star

We study the dynamics of a charged particle in the field of a slowly rotating compact star in the gravitoelectromagnetic approximation to the geodesic equation . The star is assumed to be surrounded by an ideal, highly conducting plasma (taken as a magnetohydrodynamic fluid) with a stationary, axially symmetric electromagnetic field. The general relativistic Maxwell equations are solved to obtain the effects of the background spacetime on the electromagnetic field in the linearized Kerr spacetime. The equations of motion are then set up and solved numerically to incorporate the gravitational as well as the electromagnetic effects. The analysis shows that in the slow rotation approximation the frame dragging effects on the electromagnetic field are absent. However the particle is directly effected by the rotating gravitational source such that close to the star the gravitational and electromagnetic field produce contrary effects on the particle's trajectory.

astro-ph↗

arXiv2003

Gravitomagnetic Resonance Shift due to a Slowly Rotating Compact Star

The effect of a slowly rotating mass on a forced harmonic oscillator with two degrees of freedom is studied in the weak field approximation. It is found that according to the general theory of relativity there is a shift in the resonat frequency of the oscillator which depends on the density and rotational frequency of the gravitational source. The proposed shift is quite small under normal physical situations however it is estimated that for compact x-ray sources such as white dwarfs, pulsars, and neutron stars the shift is quite appreciable.

astro-ph↗