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arXiv · 0812.4694

Test membranes in Riemann-Cartan spacetimes

Milovan Vasilic·Marko Vojinovic
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Abstract

The dynamics of brane-like extended objects in spacetimes with torsion is derived from the conservation equations of stress-energy and spin tensors. Thus obtained world-sheet equations are applied to macroscopic test membranes made of spinning matter. Specifically, we consider membranes with maximally symmetric distribution of stress-energy and spin. These are characterized by two constants only: the tension and spin magnitude. By solving the world-sheet equations, we discover a similarity between such membranes in Riemann-Cartan backgrounds, and string theory membranes in low-energy string backgrounds. In the second part of the paper, we apply this result to cylindrical membranes wrapped around the extra compact dimension of a $(D+1)$-dimensional spacetime. In the narrow membrane limit, we discover how effective macroscopic strings couple to torsion. An observed similarity with the string sigma model is noted.

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Milovan Vasilic, Marko Vojinovic. 2010-03-10. Test membranes in Riemann-Cartan spacetimes. https://doi.org/10.1103/physrevd.81.024025

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