Flowing with displacements and tilts: surface operators in O(N) models
Open Access
- 14 October 2026
- journal article
- research article
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2026 (10) , 157
Abstract
A bstract: Defect conformal field theories have special operators of protected dimension known as displacements and tilts. They arise due to the breaking of global symmetries by the defect and the normalisations of their two-point functions are characteristics of the defect. In the case of surface defects, these normalisations are related to some of the anomaly coefficients in the surface effective action. To study these operators and their flows between different defect renormalization group fixed points we present an elegant approach using conformal perturbation theory that easily reproduces the known examples from the critical Wilson-Fisher O( N ) model in 4 − ε dimensions and allows us to construct new ones in other multiscalar theories. In all the systems that we study the flows are short and under full control, as is the change of the displacement and tilt normalizations. We point out some novel features like the existence of vortices when the defect conformal manifold is not simply connected. In addition to regular human labour, this work relied heavily on generative AI; see full disclosure in methodology section.Keywords
This publication has 48 references indexed in Scilit:
- Yang-Mills flux tube in AdSJournal of High Energy Physics, 2026
- There and back again: bulk-to-defect via Ward identitiesJournal of High Energy Physics, 2026
- Surprises in the ordinary: O(N) invariant surface defect in the ϵ-expansionJournal of High Energy Physics, 2025
- 1/3 BPS loops and defect CFTs in ABJM theoryJournal of High Energy Physics, 2023
- A sum rule for boundary contributions to the trace anomalyJournal of High Energy Physics, 2022
- Defect CFT techniques in the 6d $ \mathcal{N} $ = (2, 0) theoryJournal of High Energy Physics, 2021
- Irreversibility in quantum field theories with boundariesJournal of High Energy Physics, 2019
- Seeking fixed points in multiple coupling scalar theories in the ε expansionJournal of High Energy Physics, 2018
- ’t Hooft anomalies and boundariesJournal of High Energy Physics, 2018
- Rényi entropy and conformal defectsJournal of High Energy Physics, 2016