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arXiv · 2306.17128

A note on null distance and causality encoding

Gregory J. Galloway
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Abstract

Under natural conditions, the null distance introduced by Sormani and Vega [10] is a metric space distance function on spacetime, which, in a certain precise sense, can encode the causality of spacetime. The null distance function requires the choice of a time function. The purpose of this note is to observe that the causality assumptions related to such a choice in results used to establish global encoding of causality, due to Sakovich and Sormani [9] and to Burtscher and Garc\'ia-Heveling [2], can be weakened.

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Gregory J. Galloway. 2023-06-29. A note on null distance and causality encoding. https://arxiv.org/abs/2306.17128

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