Kinematics and dynamics off(R) theories of gravity |
| |
Authors: | Steve Rippl Henk van Elst Reza Tavakol David Taylor |
| |
Institution: | (1) Astronomy Unit, School of Mathematical Sciences, Queen Mary and Westfield College, Mile End Road, E1 4NS London, UK;(2) Department of Computational and Applied Mathematics, University of the Witwatersrand, PO WITS, 2050, South Africa;(3) School of Mathematical Studies, University of Portsmouth, PO1 2EG, UK |
| |
Abstract: | We generalise the equations governing relativistic fluid dynamics given by Ehlers and Ellis for general relativity, and by Maartens and Taylor for quadratic theories, to generalisedf(R) theories of gravity. In view of the usefulness of this alternative framework to general relativity, its generalisation can be of potential importance for deriving analogous results to those obtained in general relativity. We generalise, as an example, the results of Maartens and Taylor to show that within the framework of generalf(R) theories, a perfect fluid spacetime with vanishing vorticity, shear and acceleration is Friedmann-Lemaître-Robertson-Walker only if the fluid has in addition a barotropic equation of state. It then follows that the Ehlers-Geren-Sachs theorem and its almost extension also hold forf(R) theories of gravity. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|