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arXiv · 2506.09880

Radon Transforms and the SYK model

Michael Stone
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Abstract

Motivated by recent work on the Sachdev-Ye-Kitaev (SYK) model, we consider the effect of Radon or X-ray transformations, on the Laplace eigenfunctions in hyperbolic Bolyai-Lobachevsky space. We show that the Radon map from this space to Lorentzian-signature Anti-de Sitter or de Sitter space is easier to interpret if we use the Poincare disc model and eigenfunctions rather than the upper-half-plane model. In particular, this version of the transform reveals the geometric origin of the boundary conditions imposed on the eigenfunctions that are involved in calculating the SYK four-point function.

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Michael Stone. 2025-06-11. Radon Transforms and the SYK model. https://arxiv.org/abs/2506.09880

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