arXiv subjects

M. Azam

Publications and source records attributed to M. Azam.

21 records · Page 2Linked to original sources

arXiv2012

Effects of Electromagnetic Field on the Dynamical Instability of Cylindrical Collapse

The objective of this paper is to discuss the dynamical instability in the context of Newtonian and post Newtonian regimes. For this purpose, we consider non-viscous heat conducting charged isotropic fluid as a collapsing matter with cylindrical symmetry. Darmois junction conditions are formulated. The perturbation scheme is applied to investigate the influence of dissipation and electromagnetic field on the dynamical instability. We conclude that the adiabatic index $Γ$ has smaller value for such a fluid in cylindrically symmetric than isotropic sphere.

gr-qc↗

arXiv2006

Energy-Momentum Distribution: Some Examples

In this paper, we elaborate the problem of energy-momentum in General Relativity with the help of some well-known solutions. In this connection, we use the prescriptions of Einstein, Landau-Lifshitz, Papapetrou and Möller to compute the energy-momentum densities for four exact solutions of the Einstein field equations. We take the gravitational waves, special class of Ferrari-Ibanez degenerate solution, Senovilla-Vera dust solution and Wainwright-Marshman solution. It turns out that these prescriptions do provide consistent results for special class of Ferrari-Ibanez degenerate solution and Wainwright-Marshman solution but inconsistent results for gravitational waves and Senovilla-Vera dust solution.

gr-qc↗

arXiv2005

A simple analytical calculation of mean-field potential in heavy nuclei

In many-body theory of particles with long range interaction potential, such as the potential of Newtonian gravity and its relativistic generalization, Newton-Birkhoff theorem plays a very important role. This theorem is violated in the case of short range interaction potential, such as the Yukawa potential in nuclear physics. We discuss the relevance of this in the many-body treatment of heavy nuclei. In particular, using techniques similar to those in Newtonian gravity, we calculate analytically the mean-field potential in heavy nuclei. The mean-field potential thus calculated depends on well known quantities such as the pion-nucleon coupling constant, inverse pion mass, nuclear radius and density. The qualitative features of the mean-field potential thus obtained is similar to the well known phenomenological Wood-Saxon potential.

nucl-th↗