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arXiv · 1611.04143

Rainich Conditions in (2+1)-Dimensional Gravity

D. S. Krongos·C. G. Torre
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Abstract

In (3 + 1) spacetime dimensions the Rainich conditions are a set of equations expressed solely in terms of the metric tensor which are equivalent to the Einstein-Maxwell equations for non-null electromagnetic fields. Here we provide the analogous conditions for (2 + 1)-dimensional gravity coupled to electromagnetism. Both the non-null and null cases are treated. The construction of these conditions is based upon reducing the problem to that of gravity coupled to a scalar field, which we have treated elsewhere. These conditions can be easily extended to other theories of (2 + 1)-dimensional gravity. For example, we apply the geometrization conditions to topologically massive gravity coupled to the electromagnetic field and obtain a family of plane-fronted wave solutions.

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D. S. Krongos, C. G. Torre. 2016-11-13. Rainich Conditions in (2+1)-Dimensional Gravity. https://doi.org/10.1063/1.4974091

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