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Several exact cosmological solutions of a metric-affine theory of gravity with two torsion functions are presented. These solutions give a essentially different explanation from the one in most of previous works to the cause of the…

广义相对论与量子宇宙学 · 物理学 2015-06-05 Guoying Chee , Yongxin Guo

Curvature and torsion are the two tensors characterizing a general Riemannian spacetime. In Einstein's general theory of gravitation, with torsion postulated to vanish and the affine connection identified to the Christoffel symbol, only the…

广义相对论与量子宇宙学 · 物理学 2013-09-05 H. T Nieh

In this work we present the general differential geometry of a background in which the space-time has both torsion and curvature with internal symmetries being described by gauge fields, and that is equipped to couple spinorial matter…

广义相对论与量子宇宙学 · 物理学 2022-04-20 Luca Fabbri

A theory of gravity with torsion is examined in which the torsion tensor is constructed from the exterior derivative of an antisymmetric rank two potential plus the dual of the gradient of a scalar field. Field equations for the theory are…

广义相对论与量子宇宙学 · 物理学 2009-11-07 Charro Gruver , Richard Hammond , P. F. Kelly

We introduce and develop the 1+3 covariant approach to relativity and cosmology to spacetimes of arbitrary dimensions that have nonzero torsion and do not satisfy the metricity condition. Focusing on timelike observers, we identify and…

广义相对论与量子宇宙学 · 物理学 2018-12-05 Damianos Iosifidis , Christos G. Tsagas , Anastasios C. Petkou

We derive the evolution equation for the second order curvature perturbation using standard techniques of cosmological perturbation theory. We do this for different definitions of the gauge invariant curvature perturbation, arising from…

宇宙学与河外天体物理 · 物理学 2016-02-09 Pedro Carrilho , Karim A. Malik

We look into the general aspects of space-time symmetries in presence of torsion, and how the latter is affected by such symmetries. Focusing in particular to space-times which either exhibit maximal symmetry on their own, or could be…

广义相对论与量子宇宙学 · 物理学 2017-08-18 Sourav Sur , Arshdeep Singh Bhatia

Given a spacetime with nonvanishing torsion, we discuss the equation for the evolution of the separation vector between infinitesimally close curves in a congruence. We show that the presence of a torsion field leads, in general, to tangent…

广义相对论与量子宇宙学 · 物理学 2017-09-22 Paulo Luz , Vincenzo Vitagliano

f(R)-gravity with geometric torsion (not related to any spin fluid) is considered in a cosmological context. We derive the field equations in vacuum and in presence of perfect-fluid matter and discuss the related cosmological models.…

广义相对论与量子宇宙学 · 物理学 2009-01-21 S. Capozziello , R. Cianci , C. Stornaiolo , S. Vignolo

We explore spacetime torsion in a two-dimensional setting, wherein it corresponds to a vector field. Without invoking field equations of a particular gravitational theory, we develop visualization techniques for such torsion fields,…

广义相对论与量子宇宙学 · 物理学 2025-04-09 Jens Boos

The dynamics of the torsion field is analyzed in the framework of the Covariant Canonical Gauge Theory of Gravity (CCGG), a De~Donder-Weyl Hamiltonian formulation of gauge gravity. The action is quadratic in both, the torsion and the…

广义相对论与量子宇宙学 · 物理学 2024-05-29 Vladimir Denk , David Vasak , Johannes Kirsch

An earlier scheme [arXiv:2404.03360], where torsion plays an essential part in a flat spacetime account of fermion spin, is extended to spacetimes with non-zero Riemann curvature. It is found that further essential features of the fermion,…

广义相对论与量子宇宙学 · 物理学 2024-04-18 William J. Leigh

Geometric torsions are torsions of acyclic complexes of vector spaces which consist of differentials of geometric quantities assigned to the elements of a manifold triangulation. We use geometric torsions to construct invariants for a…

几何拓扑 · 数学 2009-11-13 I. G. Korepanov

The essentially unique torsionful version of the classical two-component spinor formalisms of Infeld and van der Waerden is presented. All the metric spinors and connecting objects that arise here are formally the same as the ones borne by…

数学物理 · 物理学 2015-01-26 J. G. Cardoso

At first we introduce the space-time manifold and we compare some aspects of Riemannian and Lorentzian geometry such as the distance function and the relations between topology and curvature. We then define spinor structures in general…

广义相对论与量子宇宙学 · 物理学 2015-06-25 Giampiero Esposito

Higher-order tensors appear in various areas of mechanics as well as physics, medicine or earth sciences. As these tensors are highly complex, most are not well understood. Thus, the analysis and the visualization process form a highly…

数学物理 · 物理学 2023-05-04 Anja Barz , Chiara Hergl , Gerik Scheuermann

The influence of the torsion on the relative velocity and on the relative acceleration between particles (points) in spaces with an affine connection and a metric [$(L_n,g)$-spaces] and in (pseudo) Riemannian spaces with torsion…

广义相对论与量子宇宙学 · 物理学 2007-05-23 S. Manoff

We revisit an emergent gravity scenario in $(4+1)$ dimensions underlying a propagating geometric torsion ${\cal H}_3$ with a renewed interest. We show that a pair-symmetric $4$th order curvature tensor is sourced by a two-form Neveu-Schwarz…

高能物理 - 理论 · 物理学 2021-02-24 R. Nitish , Supriya Kar

We study null geodesic congruences (NGCs) in the presence of spacetime torsion, recovering and extending results in the literature. Only the highest spin irreducible component of torsion gives a proper acceleration with respect to metric…

广义相对论与量子宇宙学 · 物理学 2018-10-24 Simone Speziale

This article is a summary of a series of papers to be published where I examine a special kind of geometric objects that can be defined in space-time --- five-dimensional tangent vectors. Similar objects exist in any other differentiable…

数学物理 · 物理学 2007-05-23 Alexander Krasulin
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