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arXiv · 2611.07007

Critical collapse remains discretely self-similar at large D

Christian Ecker·Florian Ecker·Daniel Grumiller
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Abstract

When matter collapses at the threshold of black hole formation spacetime typically has an emergent continuous or discrete symmetry, depending on the matter content. For the Einstein-Klein-Gordon model in any finite dimension D>3 the associated critical spacetime solutions exhibit discrete self-similarity, characterized by the echoing period Delta. Combining analytical and numerical results with dimensions up to D=200 we predict Delta remains finite at infinite dimension D, contrary to a recent conjecture. We find the fit Delta=1.6439+10.37/D-O(1/D^2) and provide an explicit large-D model.

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Christian Ecker, Florian Ecker, Daniel Grumiller. 2026-11-04. Critical collapse remains discretely self-similar at large D. https://arxiv.org/abs/2611.07007

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