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arXiv · 1707.00862

Unified geometrical basis for the generalized Ehlers identities and Raychaudhuri equations

Eduard G. Mychelkin·Maxim A. Makukov
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Abstract

It is shown that the timelike, spacelike and null versions of the Ehlers identity, as well as ensuing Raychaudhuri equations, might be all derived within a single geometrical approach based on the definition of the Riemann curvature tensor specified with respect to the corresponding congruence. Still, spacelike and null cases have a number of non-trivial peculiarities deserving special attention.

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Eduard G. Mychelkin, Maxim A. Makukov. 2017-10-28. Unified geometrical basis for the generalized Ehlers identities and Raychaudhuri equations. https://arxiv.org/abs/1707.00862

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