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arXiv · 2403.04281

Topology Change from Pointlike Sources

Yasha Neiman·David O'Connell
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Abstract

In this paper we study topology-changing spacetimes occurring from pointlike sources. Following an old idea of Penrose, we will opt for a non-Hausdorff model of topology change in which an initial pointlike source is ``doubled" and allowed to propagate along null rays into an eventual cobordism. By appealing to recent developments in non-Hausdorff differential geometry, we will describe and evaluate gravitational actions on these topology-changing spacetimes. Motivated by analogous results for the Trousers space, we describe a sign convention for Lorentzian angles that will ensure the dampening of our non-Hausdorff topology-changing spacetimes within a two-dimensional path integral for gravity.

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Yasha Neiman, David O'Connell. 2024-03-07. Topology Change from Pointlike Sources. https://arxiv.org/abs/2403.04281

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