cs.CVOct 1, 2026

Moore, Escher, Penrose: A Conformal Golden Braid

Authors: Sophia Feldman, Assaf Shocher

Organizations: Technion - Israel Institute of Technology

Abstract

I don't think I have ever done anything as peculiar in my life. Among other things, it shows a young man looking with interest at a print on the wall of an exhibition that features himself. How can this be? Perhaps I am not far removed from Einstein's curved universe.'' So wrote M.C. Escher about his 1956 lithograph Print Gallery. Nearly half a century later, a mathematical analysis related its geometry to an untwisted source image through a conformal power map z↦zαz \mapsto z^α, α∈Cα\in \mathbb{C}. Building on this construction, we use a frozen text-to-image diffusion model to generate new self-referential scenes. Prompting alone does not enforce the recursion, while a post-hoc transformation can leave structures poorly connected. Applying the transformation during sampling is also insufficient: the denoiser may "repair" the intended distortion or drift out of the prescribed geometry. We construct a generalized inverse T†T^\dagger of the non-invertible image transformation TT, adapted to its recursive constraint. In the idealized formulation, the Penrose identity TT†T=TTT^\dagger T = T makes TT†TT^\dagger an idempotent projection onto geometrically admissible images. Yet denoising only the transformed image remains an out-of-distribution task, even with projection. We therefore braid denoising steps with TT and T†T^\dagger: source-space steps develop the untwisted scene, while transformed-space steps refine its appearance and connections in the final geometry. We generate Print Gallery-like compositions and explore further transformations. Rather than distorting a finished image, we let the scene and its distortion develop together.

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