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arXiv · 1905.01955

The scalarized Raychaudhuri identity and its applications

Eduard G. Mychelkin·Maxim A. Makukov
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Abstract

We show that the covariant Raychaudhuri identity describing kinematic characteristics of space-time admits a representation involving a geometrical scalar $\xi$ which, depending on circumstances, might be related to, e.g., relativistic temperature or cosmological scalar field. With an appropriately chosen spacetime deformation tensor (fixing the symmetry of a problem under consideration), such scalarization opens a wide scope for physical applications. We consider few such applications including dynamics of cosmological (anti)scalar background, non-variational deduction of the field equations, scalar and black-hole thermodynamics and the reshaping of the Einstein equations into the Klein-Gordon equation in thermodynamic Killing space.

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Eduard G. Mychelkin, Maxim A. Makukov. 2019-05-06. The scalarized Raychaudhuri identity and its applications. https://doi.org/10.1103/physrevd.99.104055

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