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arXiv · 1902.08170

On the choice of a conformal Gauss gauge near the cylinder representing spatial infinity

Tim-Torben Paetz
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Abstract

A convenient approach to analyze spatial infinity is to use a cylinder representation $I$ and impose a gauge based on a congruence of conformal geodesics. This so-called conformal Gauss gauge comes along with the freedom to specify initial data for the conformal geodesics. Such a gauge has been constructed from an ordinary Cauchy surface and from past null infinity $\mathcal{J}^-$, respectively. The purpose of this note is to compare these gauges near the critical set $I^-$, where $I$ "touches" $\mathcal{J}^-$, as it turns out that they are related in a somewhat unexpected intricate way.

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Tim-Torben Paetz. 2019-02-21. On the choice of a conformal Gauss gauge near the cylinder representing spatial infinity. https://doi.org/10.1063/1.5096487

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