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Related papers: Nonstandard general relativity II

200 papers

We show that the relativistic effects are negligibly small in the non-linear density and velocity bispectra. Although the non-linearities of Einstein equation introduce additional non-linear terms to the Newtonian fluid equations, the…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-28 Sang Gyu Biern , Jinn-Ouk Gong , Donghui Jeong

We show that the Einstein equations in the vacuum are invariant under an $SO(2)$ duality symmetry which rotates the curvature 2-form into its tangent space Hodge dual. Akin to electric-magnetic duality in gauge theory, the duality operation…

High Energy Physics - Theory · Physics 2023-11-15 Uri Kol

We compute the second-order density fluctuation in the proper-time hypersurface of non-relativistic matter flows and relate it to the galaxy number density fluctuation in general relativity. At the linear order, it is equivalent to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Jaiyul Yoo

A nonlocal generalization of Einstein's theory of gravitation is constructed within the framework of the translational gauge theory of gravity. In the linear approximation, the nonlocal theory can be interpreted as linearized general…

General Relativity and Quantum Cosmology · Physics 2009-03-24 Friedrich W. Hehl , Bahram Mashhoon

The Einstein equations are integrated in the presence of two (incoming and outgoing) streams of null dust, under the assumptions of spherical symmetry and staticity. The solution is also written in double null and radiation coordinates and…

General Relativity and Quantum Cosmology · Physics 2010-11-19 László Á. Gergely

We report on general relativistic calculations of quasiequilibrium configurations of binary neutron stars in circular orbits with zero vorticity. These configurations are expected to represent realistic situations as opposed to corotating…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. Bonazzola , E. Gourgoulhon , J. -A. Marck

A spherically symmetric comoving fluid solution of Einstein's equations is adapted for cosmological application by extending the geometry of standard FRW cosmology using a generalised curvature term. The resulting model retains many of the…

General Relativity and Quantum Cosmology · Physics 2009-09-15 Ron Wiltshire

In the spirit of the Newtonian theory, we characterize spherically symmetric empty space in general relativity in terms of energy density measured by a static observer and convergence density experienced by null and timelike congruences. It…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Naresh Dadhich

In the framework of non-riemannian geometry, we derive exact static vacuum solutions of the field equations obtained from the full equivalent version of the Einstein-Hilbert action when torsion degrees of freedom are taken into account. By…

General Relativity and Quantum Cosmology · Physics 2014-12-16 Rodrigo Maier

In this talk we show a stiff fluid solution of the Einstein equations for a cylindrically symmetric spacetime. The main features of this metric are that it is non-separable in comoving coordinates for the congruence of the worldlineS of the…

General Relativity and Quantum Cosmology · Physics 2009-06-01 L. Fernández-Jambrina

Along the general framework of the gauge-invariant perturbation theory developed in the papers [K. Nakamura, Prog. Theor. Phys. {\bf 110} (2003), 723; {\it ibid}, {\bf 113} (2005), 481.], we re-derive the second-order Einstein equations on…

General Relativity and Quantum Cosmology · Physics 2009-07-03 Kouji Nakamura

On the base of an exact solution for the static spherically symmetric Einstein equations with the quintessential dark matter, we explain the asymptotic behavior of rotation curves in spiral galaxies. The parameter of the quintessence state,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 V. V. Kiselev

We discuss the question of gauge choice when analysing relativistic density perturbations at second order. We compare Newtonian and General Relativistic approaches. Some misconceptions in the recent literature are addressed. We show that…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Daniele Bertacca , Nicola Bartolo , Marco Bruni , Kazuya Koyama , Roy Maartens , Sabino Matarrese , Misao Sasaki , David Wands

Einstein field equations under spherically symmetric space-times are considered here in connection to dark energy investigation. A set of solutions are obtained for a kinematical $\Lambda$ model, viz., $\Lambda \sim (\dot a/a)^2$ without…

General Relativity and Quantum Cosmology · Physics 2009-05-12 Utpal Mukhopadhyay , P. C. Ray , Saibal Ray , S. B. Datta Choudhury

Certain exact solutions of the Einstein field equations over nonsimply-connected manifolds are reviewed. These solutions are spherically symmetric and have no curvature singularity. They provide a regularization of the standard…

General Relativity and Quantum Cosmology · Physics 2015-06-17 F. R. Klinkhamer

We investigate insterstellar gas spheres by determining the metric functions, the material distribution, and the features of particle orbits in terms of stability and geodesics. An exact solution of the Einstein's equations for interstellar…

General Relativity and Quantum Cosmology · Physics 2017-08-21 Dániel Barta

In analogy with the standard derivation of the Schwarzschild solution, we find all static, cylindrically symmetric solutions of the Einstein field equations for vacuum. These include not only the well known cone solution, which is locally…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Cynthia S. Trendafilova , Stephen A. Fulling

Solutions to Einstein's vacuum equations in three dimensions are locally maximally symmetric. They are distinguished by their global properties and their investigation often requires a choice of gauge. Although analyses of this sort have…

High Energy Physics - Theory · Physics 2020-11-24 Luca Ciambelli , Charles Marteau , P. Marios Petropoulos , Romain Ruzziconi

Solutions of the stationary axisymmetric Einstein equations describing the interior of circularly rotating dust are investigated in order to study their potential applicability as galaxy models. It is shown that such interior solutions…

Astrophysics · Physics 2007-12-30 Tobias Zingg , Andreas Aste , Dirk Trautmann

Exact solutions of the Einstein's field equations describing a spherically symmetric cosmological model without a big bang or any other kind of singularity recently obtained by Dadhich and Patel (2000) are revisited. The matter content of…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Anirudh Pradhan , Kashika Srivastava , Amrit Lal Ahuja