Did a 1-dimensional magnet detect a 248-dimensional Lie algebra?

Abstract

About a year ago, a team of physicists reported in Science that they had observed "evidence for E8 symmetry" in the laboratory. This expository article is aimed at mathematicians and explains the chain of reasoning connecting measurements on a quasi-1-dimensional magnet with a 248-dimensional Lie algebra.

v2: Added some material clarifying the word "evidence" and the precise role of E8 in the theory // v3: many small changes to the exposition

References in corpus (2)

• Quantum criticality in an Ising chain: experimental evidence for emergent E8 symmetry
• An Exceptionally Simple Theory of Everything

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• Noncommuting local common causes for correlations violating the Clauser-Horne inequality
• Noncommutative Common Cause Principles in Algebraic Quantum Field Theory
• Exceptional Periodicity and Magic Star Algebras. I : Foundations