What's Done Cannot Be Undone: TASI Lectures on Non-Invertible Symmetries

Shu-Heng Shao

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arXiv · 2308.00747

What's Done Cannot Be Undone: TASI Lectures on Non-Invertible Symmetries

Shu-Heng Shao

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Abstract

We survey recent developments in a novel kind of generalized global symmetry, the non-invertible symmetry, in diverse spacetime dimensions. We start with several different but related constructions of the non-invertible Kramers-Wannier duality symmetry in the Ising model, and conclude with a new interpretation for the neutral pion decay and other applications. These notes are based on lectures given at the TASI 2023 summer school "Aspects of Symmetry."

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Shu-Heng Shao. 2023-08-01. What's Done Cannot Be Undone: TASI Lectures on Non-Invertible Symmetries. https://arxiv.org/abs/2308.00747

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