Schwarzian transformations at null infinity

Kevin Nguyen

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arXiv · 2201.09640

Schwarzian transformations at null infinity

Kevin Nguyen

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Abstract

I describe the Schwarzian behavior of the gravitational field at null infinity under superrotations, to be understood as an \textit{unobservable} gauge artifact. To this end I review the induced geometry of null infinity and the construction of the gauge-invariant News tensor that characterizes gravitational radiation. I discuss potentially important implications for the celestial holography program, suggesting in particular that the uplift of the AdS$_3$/CFT$_2$ correspondence directly relates to the unobservable gauge sector.

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Kevin Nguyen. 2022-01-24. Schwarzian transformations at null infinity. https://arxiv.org/abs/2201.09640

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