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arXiv · 0807.3041

A Kirchhoff-like conservation law in Regge calculus

Adrian P. Gentle·Arkady Kheyfets·Jonathan R. McDonald·Warner A. Miller
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Abstract

Simplicial lattices provide an elegant framework for discrete spacetimes. The inherent orthogonality between a simplicial lattice and its circumcentric dual yields an austere representation of spacetime which provides a conceptually simple form of Einstein's geometric theory of gravitation. A sufficient understanding of simplicial spacetimes has been demonstrated in the literature for spacetimes devoid of all non-gravitational sources. However, this understanding has not been adequately extended to non-vacuum spacetime models. Consequently, a deep understanding of the diffeomorphic structure of the discrete theory is lacking. Conservation laws and symmetry properties are attractive starting points for coupling matter with the lattice. We present a simplicial form of the contracted Bianchi identity which is based on the E. Cartan moment of rotation operator. This identity manifests itself in the conceptually-simple form of a Kirchhoff-like conservation law. This conservation law enables one to extend Regge Calculus to non-vacuum spacetimes and provides a deeper understanding of the simplicial diffeomorphism group.

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Adrian P. Gentle, Arkady Kheyfets, Jonathan R. McDonald, Warner A. Miller. 2009-03-24. A Kirchhoff-like conservation law in Regge calculus. https://doi.org/10.1088/0264-9381%2F26%2F1%2F015005

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