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Defect Conformal Manifolds from Phantom Noninvertible Symmetries

Andrea Antinucci1, Christian Copetti1, Giovanni Galati2, and Giovanni Rizi3

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Phys. Rev. Lett. 135, 211602 – Published 17 November, 2025

DOI: https://doi.org/10.1103/w43n-sybv

Abstract

We explore a general mechanism that allows (1+1)d CFTs to have interesting interface conformal manifolds even in the absence of any continuous internal symmetry or supersymmetry. This is made possible by the breaking of an enhanced continuous symmetry—which is generically noninvertible—arising in the folded theory. We provide several examples and showcase the power of the symmetry-based approach by computing the evolution of the reflection coefficient along the defect conformal manifold. We also discuss higher-dimensional generalizations and we comment on no-go theorems.

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Phys. Rev. Lett. 135, 211602– Published 17 November, 2025
  • Received 24 June 2025
  • Accepted 23 October 2025
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