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Causal symmetries

Alfonso García-Parrado·José M. M. Senovilla
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Abstract

Based on the recent work \cite{PII} we put forward a new type of transformation for Lorentzian manifolds characterized by mapping every causal future-directed vector onto a causal future-directed vector. The set of all such transformations, which we call causal symmetries, has the structure of a submonoid which contains as its maximal subgroup the set of conformal transformations. We find the necessary and sufficient conditions for a vector field $\xiv$ to be the infinitesimal generator of a one-parameter submonoid of pure causal symmetries. We speculate about possible applications to gravitation theory by means of some relevant examples.

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Alfonso García-Parrado, José M. M. Senovilla. 2003-03-05. Causal symmetries. https://doi.org/10.1088/0264-9381%2F20%2F9%2F103

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