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arXiv · 1309.5157

Level sets of the lapse function in static GR

Carla Cederbaum
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Abstract

We present a novel physical interpretation of the level sets of the (canonical) lapse function in static isolated general relativistic space-times. Our interpretation uses a notion of 'constrained test particles'. It leads to a definition of gravitational force on test particles and to a previously unknown uniqueness result for the lapse function. In Section 5, we discuss 'photon spheres' in static isolated relativistic space-times and relate them to the level sets of the lapse function.

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Carla Cederbaum. 2013-09-20. Level sets of the lapse function in static GR. https://doi.org/10.1007/978-3-319-18335-0

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