Table of Contents
Physics Research International
Volume 2015 (2015), Article ID 152846, 19 pages
http://dx.doi.org/10.1155/2015/152846
Research Article

Modified Theories of Gravitation behind the Spacetime Deformation

Ambartsumian Byurakan Astrophysical Observatory, Aragatsotn, 378433 Byurakan, Armenia

Received 6 June 2014; Revised 1 September 2014; Accepted 11 September 2014

Academic Editor: Bennie F. L. Ward

Copyright © 2015 Gagik Ter-Kazarian. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In the framework of proposed theory of spacetime deformation/distortion, we have a way to deform the spacetime through a nontrivial choice of the distortion-complex, displaying different connections, which may reveal different post-Riemannian spacetime structures as corollary. We extend this theory to address, in particular, the gauge model of the most general metric-affine gravity carrying both nontrivial torsion and nonmetricity. This model is constructed in the framework of the first order Lagrangian expressed in terms of the gauge potentials and their first derivatives. The equations of the standard theory, which have no propagating modes for torsion, can be equivalently replaced in modified framework by the modified equations, which in the limit of reducing the affine group leads to the modified Einstein-Cartan theory with dynamical torsion and beyond. In testing the modified framework for various particular cases, we use the Lagrange multipliers for extinguishing nonmetricity and torsion.