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arXiv · 2509.08038

Free and Interacting Fermionic Conformal Field Theories on the Fuzzy Sphere

Zheng Zhou·Davide Gaiotto·Yin-Chen He
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Abstract

The fuzzy-sphere regularisation is a powerful tool to study conformal field theories (CFT) in three spacetime dimensions. In this paper, we extend its scope to CFTs with local fermionic operators. We realise the free-Majorana-fermion CFT on a set-up with one flavour of bosons and one flavour of fermions on the lowest Landau level with a $1/2$ angular momentum mismatch and allow conversion between two bosons and two fermions, and use a relative chemical potential as the tuning parameter. On the phase diagram, we observe two continuous transitions described respectively by a free Majorana fermion and a gauged Ising CFT. We numerically confirm the emergent conformal symmetry through the operator spectrum and the two-point correlation function of the local Majorana fermion. We further establish a correspondence between the fuzzy-sphere models and the field-theory Lagrangians, and extend it to an interacting fermionic CFT -- the super-Ising theory with emergent super-conformal symmetry.

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Zheng Zhou, Davide Gaiotto, Yin-Chen He. 2025-09-09. Free and Interacting Fermionic Conformal Field Theories on the Fuzzy Sphere. https://doi.org/10.1103/fkkl-9tw2

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