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A<sc>bstract</sc> We study anO(N) invariant surface defect in the Wilson-Fisher conformal field theory (CFT) ind= 4 –ϵdimensions. This defect is defined by mass deformation on a two-dimensional surface that generates localized disorder and is conjectured to factorize into a pair of ordinary boundary conditions ind= 3. We determine defect CFT data associated with the lightestO(N) singlet and vector operators up to the third order in theϵ-expansion, find agreements with results from numerical methods and provide support for the factorization proposal ind= 3. Along the way, we observe surprising non-renormalization properties for surface anomalous dimensions and operator-product-expansion coefficients in theϵ-expansion. We also analyze the full conformal anomalies for the surface defect.
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This content will become publicly available on April 1, 2026
First order corrections to the homogenized scattering resonances for periodic scatterers
We consider the asymptotic analysis of the resonances of the scalar Helmholtz equation corresponding to a bounded scatterer with a periodic index of refraction and small period size ϵ. When the homogenized resonance is simple, we derive an explicit formula for the first order corrections to the limiting resonances. For scatterers with boundary that has a flat part of rational normal, the first order corrections are not unique and depend on the interaction of the boundary of the scatterer with the microstructure. In this case the resonances converge only O(ϵ) in general. For smooth domains with no flat parts, the resonances converge o(ϵ), but the convergence is nonetheless sub-quadratic.
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- PAR ID:
- 10617609
- Publisher / Repository:
- Journal of Mathematical Physics
- Date Published:
- Journal Name:
- Journal of Mathematical Physics
- Volume:
- 66
- Issue:
- 4
- ISSN:
- 0022-2488
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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