Πλοήγηση ανά Συγγραφέα "Grammenos, T."
-
Conditional symmetries and the canonical quantization of constrained minisuperspace actions: The Schwarzschild case
Christodoulakis, T.; Dimakis, N.; Terzis, P. A.; Doulis, G.; Grammenos, T.; Melas, E.; Spanou, A. (2013)A conditional symmetry is defined, in the phase space of a quadratic in velocities constrained action, as a simultaneous. conformal symmetry of the supermetric and the superpotential. Iris proven that such a symmetry ... -
Decoupling of the general scalar field mode and the solution space for Bianchi type I and V cosmologies coupled to perfect fluid sources
Christodoulakis, T.; Grammenos, T.; Helias, C.; Kevrekidis, P. G.; Spanou, A. (2006)The scalar field degree of freedom in Einstein's plus matter field equations is decoupled for Bianchi type I and V general cosmological models. The source, apart from the minimally coupled scalar field with arbitrary ... -
Distribution of Energy-Momentum in a Schwarzschild-Quintessence Space-Time Geometry
Radinschi, I.; Grammenos, T.; Spanou, A. (2013)An analysis of the energy-momentum localization for a four-dimensional Schwarzschild black hole surrounded by dark energy in the form of quintessence is presented in order to provide expressions for the distributions of ... -
Energy and momentum distributions of the magnetic solution to (2+1) Einstein-Maxwell gravity
Grammenos, T. (2005)We use Moller's energy-momentum complex in order to explicitly evaluate the energy and momentum density distributions associated with the three-dimensional magnetic solution to the Einstein-Maxwell equations. The magnetic ... -
Energy distribution in a Schwarzschild-like spacetime
Grammenos, T.; Radinschi, I. (2007)In this paper, utilizing Moller's energy-momentum complex, we explicitly evaluate the energy and momentum density associated with a metric describing a four-dimensional, Schwarzschild-like, spacetime derived from an effective ... -
Energy Distribution of a Regular Black Hole Solution in Einstein-Nonlinear Electrodynamics
Radinschi, I.; Rahaman, F.; Grammenos, T.; Spanou, A.; Islam, S. (2015)A study about the energy momentum of a new four-dimensional spherically symmetric, static and charged, regular black hole solution developed in the context of general relativity coupled to nonlinear electrodynamics is ... -
Energy distribution of the Einstein-Klein-Gordon system for a static spherically symmetric space-time in (2+1) dimensions
Radinschi, I.; Grammenos, T. (2006)We use Moller's energy-momentum complex in order to explicitly compute the energy and momentum density distributions for an exact solution of Einstein's field equations with a negative cosmological constant, minimally ... -
ENERGY LOCALIZATION FOR DILATONIC BLACK HOLE GEOMETRIES WITH A PURE MONOPOLE FIELD
Radinschi, I.; Grammenos, T. (2010)The energy distribution of black holes with a dilaton and a pure monopole field is calculated by using Moller's energy-momentum complex. The four-dimensional space-times considered are static, spherically symmetric and ... -
Energy-momentum complexes for a stringy black hole geometry in a low-energy effective string theory
Radinschi, I.; Grammenos, T. (2009)The energy and momentum distributions for a four-dimensional, magnetically charged, stringy black hole geometry, in a low-energy effective string theory, are calculated. To this purpose, the energy-momentum complexes of ... -
Energy-Momentum Localization for a Space-Time Geometry Exterior to a Black Hole in the Brane World
Radinschi, I.; Grammenos, T.; Spanou, A. (2013)In general relativity one of the most fundamental issues consists in defining a generally acceptable definition for the energy-momentum density. As a consequence, many coordinate-dependent definitions have been presented, ... -
Fluid ordering effects and density variations in nanochannel flows: a quasicontinuum theory
Grammenos, T.; Giannakopoulos, A. (2014)A quasicontinuum self-diffusion theory that can capture the fluid ordering effects and density variations predicted by nonequilibrium molecular dynamics in nanochannel flows is presented. The physics of the problem suggests ... -
Localization of energy for a regular black hole solution in an asymptotically de Sitter spacetime geometry
Radinschi, I.; Grammenos, T.; Spanou, A. (2011)The energy and momentum distributions of a regular black hole in a four-dimensional, asymptotically de Sitter spacetime geometry are computed, whereby the Einstein, Landau-Lifshitz, Weinberg and Moller energy-momentum ... -
Locally homogeneous spaces, induced Killing vector fields and applications to Bianchi prototypes
Papadopoulos, G. O.; Grammenos, T. (2012)An answer to the question: Can, in general, the adoption of a given symmetry induce a further symmetry, which might be hidden at a first level? has been attempted in the context of differential geometry of locally homogeneous ... -
Moller's energy-momentum complex for a spacetime geometry on a noncommutative curved D3-brane
Radinschi, I.; Grammenos, T. (2008)Moller's energy-momentum complex is employed in order to determine the energy and momentum distributions for a spacetime described by a "generalized Schwarzschild" geometry in (3+1)-dimensions on a noncommutative curved ... -
Towards canonical quantum gravity for 3+1 geometries admitting maximally symmetric two-dimensional surfaces
Christodoulakis, T.; Doulis, G.; Terzis, P. A.; Melas, E.; Grammenos, T.; Papadopoulos, G. O.; Spanou, A. (2010)The canonical decomposition of all 3+1 geometries admitting two-dimensional space-like surfaces is exhibited as a generalization of a previous work. A proposal, consisting of a specific renormalization Assumption and an ... -
Towards canonical quantum gravity for G(1) geometries in 2+1 dimensions with Lambda-term
Christodoulakis, T.; Doulis, G.; Terzis, P. A.; Melas, E.; Grammenos, T.; Papadopoulos, G. O.; Spanou, A. (2008)The canonical analysis and subsequent quantization of the (2+1)-dimensional action of pure gravity plus a cosmological constant term is considered, under the assumption of the existence of one spacelike Killing vector ...