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相关论文: Space-time revisited

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Torsion and curvature could play a fundamental role in explaining cosmological dynamics. f(R)-gravity with torsion is an approach aimed to encompass in a comprehensive scheme all the Dark Side of the Universe (Dark Energy and Dark Matter).…

广义相对论与量子宇宙学 · 物理学 2014-11-20 S. Capozziello , S. Vignolo

Based on the consideration of naturalness and physical facts in Einstein's theories of relativity, a nontrivial spacetime physical picture, which has a slight difference from the standard one, is introduced by making a further distinction…

高能物理 - 理论 · 物理学 2016-01-27 ChiYi Chen

The general world model for homogeneous and isotropic universe has been roposed. For this purpose, we introduce a global and fiducial system of reference (world reference frame) constructed on a 5-dimensional space-time that is embedding…

天体物理学 · 物理学 2008-03-04 Chan-Gyung Park

Torsion and nonmetricity are inherent ingredients in modifications of Eintein's gravity that are based on affine spacetime geometries. In the context of pure f(R) gravity we discuss here, in some detail, the relatively unnoticed duality…

广义相对论与量子宇宙学 · 物理学 2019-05-22 Damianos Iosifidis , Anastasios C. Petkou , Christos G. Tsagas

It is shown that nonlinear terms in equations of gravitons on the background of curved space-time of the expanding Universe can solve the problem of the negative square of the effective mass formally arising in linear approximation for…

广义相对论与量子宇宙学 · 物理学 2010-10-12 A. A. Grib , V. Yu. Dorofeev

In models of emergent gravity the metric arises as the expectation value of some collective field. Usually, many different collective fields with appropriate tensor properties are candidates for a metric. Which collective field describes…

广义相对论与量子宇宙学 · 物理学 2015-06-04 C. Wetterich

We explore the possibility of realizing a non-singular bounce in the early universe within the framework of modified gravity with spacetime torsion. In Einstein Cartan theory, torsion is embedded in the spacetime by adding an antisymmetric…

广义相对论与量子宇宙学 · 物理学 2026-01-21 Sonej Alam , Somasri Sen , Soumitra Sengupta

The Polynomial Affine Gravity is an alternative gravitational model, where the interactions are mediated solely by the affine connection, instead of the metric tensor. In this paper, we explore the space of solutions to the field equations…

广义相对论与量子宇宙学 · 物理学 2024-06-05 Oscar Castillo-Felisola , Bastian Grez , Gonzalo J. Olmo , Oscar Orellana , José Perdiguero Gárate

Starting from an affinely connected space, we consider a model of gravity whose fundamental field is the connection. We build up the action using as sole premise the invariance under diffeomorphisms, and study the consequences of a…

广义相对论与量子宇宙学 · 物理学 2020-04-08 Oscar Castillo-Felisola , Jose Perdiguero , Oscar Orellana , Alfonso R. Zerwekh

We study the potential effects of spacetime non-metricity in cosmology. In the spirit of Einstein-Cartan gravity, but with non-metricity replacing torsion, we consider the Einstein-Hilbert action and assume zero torsion. Adopting certain…

广义相对论与量子宇宙学 · 物理学 2023-03-29 Damianos Iosifidis , Ioannis Georgios Vogiatzis , Christos G. Tsagas

We derive the light deflection caused by the screw dislocation in space-time. Space-time is medium which can be deformed in such a way that its deformation is equivalent to the existence of metric which is equivalent to gravity. The…

高能物理 - 唯象学 · 物理学 2007-05-23 Miroslav Pardy

It is widely believed that classical gravity breaks down and quantum gravity is needed to deal with a singularity. We show that there is a class of spacetime curvature singularities which can be resolved with metric and matter field…

广义相对论与量子宇宙学 · 物理学 2021-05-26 Atsushi Naruko , Chul-Moon Yoo , Misao Sasaki

In its canonical formulation, general relativity is subject to gauge transformations that are equivalent to space-time coordinate changes of general covariance only when the gauge generators, given by the Hamiltonian and diffeomorphism…

广义相对论与量子宇宙学 · 物理学 2023-10-31 Martin Bojowald , Erick I. Duque

A global existence theorem, with respect to a geometrically defined time, is shown for Gowdy symmetric globally hyperbolic solutions of the Einstein-Vlasov system for arbitrary (in size) initial data. The spacetimes being studied contain…

广义相对论与量子宇宙学 · 物理学 2009-10-31 Hakan Andreasson

The role of torsion in f(R) gravity is considered in the framework of metric-affine formalism. We discuss the field equations in empty space and in presence of perfect fluid matter taking into account the analogy with the Palatini…

广义相对论与量子宇宙学 · 物理学 2008-11-26 S. Capozziello , R. Cianci , C. Stornaiolo , S. Vignolo

Analysis of the gravitational source for the Schwarzschild metric indicates that the time and the radial components of the energy momentum tensor are equal. Imposing such a condition on cosmology, we propose a cosmological model that is a…

天体物理学 · 物理学 2007-05-23 Yukio Tomozawa

A new method of metric space investigation, based on classification of its finite subspaces, is suggested. It admits to derive information on metric space properties which is encoded in metric. The method describes geometry in terms of only…

度量几何 · 数学 2007-05-23 Yuri A. Rylov

The Lorentzian spacetime metric is replaced by an area metric which naturally emerges as a generalized geometry in quantum string and gauge theory. Employing the area metric curvature scalar, the gravitational Einstein-Hilbert action is…

高能物理 - 理论 · 物理学 2008-11-26 Raffaele Punzi , Frederic P. Schuller , Mattias N. R. Wohlfarth

The teleparallel gravity theory, treated physically as a gauge theory of translations, naturally represents a particular case of the most general gauge-theoretic model based on the general affine group of spacetime. On the other hand,…

广义相对论与量子宇宙学 · 物理学 2009-11-07 Yu. N. Obukhov , J. G. Pereira

We propose a new theory of gravitation, in which the affine connection is the only dynamical variable describing the gravitational field. We construct the simplest dynamical Lagrangian density that is entirely composed from the connection,…

广义相对论与量子宇宙学 · 物理学 2013-12-17 Nikodem Poplawski