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arXiv · 2609.10670

3d Ising Field Theory with Magnetic Deformation: Fuzzy Sphere Meets TCSA

Giulia Fardelli·A. Liam Fitzpatrick·Emanuel Katz·Yuan Xin
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Abstract

We study the magnetic deformation of the $(2+1)$d Ising CFT, also known as Ising Field Theory (IFT), on a spatial sphere. We use the Fuzzy Sphere (FS) Ising setup and compare it to the Truncated Conformal Space Approach (TCSA). Universal, infinite volume, IFT quantities are extracted by modeling the effects of curvature, as expected from a local effective theory on the sphere. We find evidence that IFT contains a bound-state with a small binding energy. Locality also allows us to extract the same IFT quantities from different angular momentum sectors, providing additional consistency checks.

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Giulia Fardelli, A. Liam Fitzpatrick, Emanuel Katz, Yuan Xin. 2026-09-09. 3d Ising Field Theory with Magnetic Deformation: Fuzzy Sphere Meets TCSA. https://arxiv.org/abs/2609.10670

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