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Discrete Group Actions on Spacetimes: Causality Conditions and the Causal Boundary

Steven G. Harris
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Abstract

Suppose a spacetime $M$ is a quotient of a spacetime $V$ by a discrete group of isometries. It is shown how causality conditions in the two spacetimes are related, and how can one learn about the future causal boundary on $M$ by studying structures in $V$. The relations between the two are particularly simple (the boundary of the quotient is the quotient of the boundary) if both $V$ and $M$ have spacelike future boundaries and if it is known that the quotient of the future completion of $V$ is past-distinguishing. (That last assumption is automatic in the case of $M$ being multi-warped.)

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Steven G. Harris. 2003-10-14. Discrete Group Actions on Spacetimes: Causality Conditions and the Causal Boundary. https://doi.org/10.1088/0264-9381%2F21%2F4%2F032

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