oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Spacetime structure of an inflating global monopole  [PDF]
Inyong Cho,Alexander Vilenkin
Physics , 1997, DOI: 10.1103/PhysRevD.56.7621
Abstract: The evolution of a global monopole with an inflating core is investigated. An analytic expression for the exterior metric at large distances from the core is obtained. The overall spacetime structure is studied numerically, both in vacuum and in a radiation background.
Global Monopole in Asymptotically dS/AdS Spacetime  [PDF]
Xin-zhou Li,Jian-gang Hao
Physics , 2002, DOI: 10.1103/PhysRevD.66.107701
Abstract: In this paper, we investigate the global monopole in asymptotically dS/Ads spacetime and find that the mass of the monopole in the asymptotically dS spacetime could be positive if the cosmological constant is greater than a critical value. This shows that the gravitational field of the global monopole could be attractive or repulsive depending on the value of the cosmological constant.
Gravitating Magnetic Monopole in the Global Monopole Spacetime  [PDF]
J. Spinelly,U. de Freitas,E. R. Bezerra de Mello
Physics , 2002, DOI: 10.1103/PhysRevD.66.024018
Abstract: In this paper we study the regular self-gravitating 't Hooft-Polyakov magnetic monopole in a global monopole spacetime. We show that for the large distance, the structure of the manifold corresponds to the Reissner-Nordstr\"{o}m spacetime with a solid angle deficit factor. Although we analyze static and spherically symmetric solutions, it is not possible to solve analytically the system of coupled differential equations and only numerical evaluations can provide detailed information about the behavior of this system at the neighborhood of the defect's core. So, for this reason we solve numerically the set of differential equations for the metric tensor and for the matter fields for different values of the Higgs field vacuum expectation value, $\eta$, and the self-coupling constant, $\lambda$.
Corrections to the fine structure constant in higher dimensional global monopole spacetime  [PDF]
Geusa de A. Marques,V. B. Bezerra
Physics , 2007,
Abstract: In this paper we use the Generalized Uncertainty Principle in order to obtain the corrections to the fine structure constant in (D+1)-dimensional global monopole spacetime. The result is particularized to D-dimensional spacetime. We also discuss the particular case D=3 corresponding to the (3+1)-dimensional global monopole spacetime.
Comment on 'Gravitating magnetic monopole in the global monopole spacetime'  [PDF]
A. Achucarro,J. Urrestilla
Physics , 2002, DOI: 10.1103/PhysRevD.68.088701
Abstract: We point out a problem with the stability of composite (global-magnetic) monopoles recently proposed by J. Spinelly, U. de Freitas and E.R. Bezerra de Mello [Phys. Rev. D66, 024018 (2002)].
Features of Motion Around Global Monopole in Asymptotically dS/AdS Spacetime  [PDF]
Jian-gang Hao,Xin-zhou Li
Physics , 2003,
Abstract: In this paper, we study the motion of test particle and light around the Global Monopole in asymptotically dS/AdS spacetime. The motion of a test particle and light in the exterior region of the global monopole in dS/AdS spacetime has been investigated. Although the test particle's motion is quite different from the case in asymptotically flat spacetime, the behaviors of light(null geodesic) remain unchanged except a energy(frequency) shift. Through a phase-plane analysis, we prove analytically that the existence of a periodic solution to the equation of motion for a test particle will not be altered by the presence of cosmological constant and the deficit angle, whose presence only affects the position and type of the critical point on the phase plane. We also show that the apparent capture section of the global monopole in dS/AdS spacetime is quite different from that in flat spacetime.
Global monopole as dual-vacuum solution in Kaluza-Klein spacetime  [PDF]
Naresh Dadhich,L. K. Patel,R. Tikekar
Physics , 1999, DOI: 10.1142/S0217732399002868
Abstract: By application of the duality transformation, which implies interchange of active and passive electric parts of the Riemann curvature (equivalent to interchange of Ricci and Einstein tensors) it is shown that the global monopole solution in the Kaluza-Klein spacetime is dual to the corresponding vacuum solution. Further we also obtain solution dual to flat space which would in general describe a massive global monopole in 4-dimensional Euclidean space and would have massless limit analogus to the 4-dimensional dual-flat solution.
Critical phenomena of gravitating monopoles in the spacetime of a global monopole  [PDF]
Yves Brihaye,Betti Hartmann
Physics , 2002, DOI: 10.1103/PhysRevD.66.064018
Abstract: We present a numerical study of critical phenomena (including the Lue-Weinberg phenomenon) arising for gravitating monopoles in a global monopole spacetime. The equations of this model have been recently studied by Spinelly et al. in a domain of parameter space away from the critical points.
Vacuum Polarization Effects in Higher Dimensional Global Monopole Spacetime  [PDF]
E. R. Bezerra de Mello
Physics , 2006,
Abstract: In this paper we analyse the vacuum polarization effects associated with a massless scalar field in higher-dimensional global monopole spacetime. Specifically we calculate the renormalized vacuum expectation value of the field square, $<\Phi^2(x)>_{Ren}$, induced by a global monopole. Two different spacetimes will be considered: $i)$ In the first, the global monopole lives in whole universe, and $ii)$ in the second, the global monopole lives in a $n=3$ dimensional sub-manifold of the higher-dimensional (bulk) spacetime in the "braneworld" scenario. In order to develop these analysis we calculate the general Euclidean scalar Green function for both spacetimes. Also a general curvature coupling parameter between the field and the geometry is admitted. We explicitly show that $<\Phi^2(x)>_{Ren}$ depends crucially on the dimension of the spacetime and on the specific geometry adopted to describe the world. We also investigate the general structure of the renormalized vacuum expectation value of the energy-momentum tensor, $_{Ren.}$.
Fermionic vacuum polarization in higher-dimensional global monopole spacetime  [PDF]
E. R. Bezerra de Mello
Physics , 2007, DOI: 10.1103/PhysRevD.76.125021
Abstract: In this paper we analyse the vacuum polarization effects associated with a massless fermionic field in a higher-dimensional global monopole spacetime in the "braneworld" scenario. In this context we admit that the our Universe, the bulk, is represented by a flat $(n-1)-$dimensional brane having a global monopole in a extra transverse three dimensional submanifold. We explicitly calculate the renormalized vacuum average of the energy-momentum tensor, $_{Ren.}$, admitting the global monopole as being a point-like object. We observe that this quantity depends crucially on the value of $n$, and we provide explicit expressions to it for specific values attributed to $n$.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.