Deviation equation in Riemann-Cartan spacetime

We derive a generalized deviation equation in Riemann-Cartan spacetime. The equation describes the dynamics of the connecting vector which links events on two general adjacent world lines. Our result is valid for any theory in a Riemann-Cartan background, in particular, it is applicable to a large class of gravitational theories which go beyond the general relativistic framework.Comment: 9 pages, 1 figur

Equations of motion in scalar-tensor theories of gravity: A covariant multipolar approach

We discuss the dynamics of extended test bodies for a large class of scalar-tensor theories of gravitation. A covariant multipolar Mathisson-Papapetrou-Dixon type of approach is used to derive the equations of motion in a systematic way for both Jordan and Einstein formulations of these theories. The results obtained provide the framework to experimentally test scalar-tensor theories by means of extended test bodies.Comment: 5 pages, RevTex forma

Conservation laws in gravity: A unified framework

We study general metric-affine theories of gravity in which the metric and connection are the two independent fundamental variables. In this framework, we use Lagrange-Noether methods to derive the identities and the conservation laws that correspond to the invariance of the action under general coordinate transformations. The results obtained are applied to generalized models with nonminimal coupling of matter and gravity, with a coupling function that depends arbitrarily on the covariant gravitational field variables.Comment: 9 pages, 1 figure, RevTex format. arXiv admin note: text overlap with arXiv:1303.605