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arXiv · 2503.05519

Note on surface defects in multiscalar critical models

Andrii Anataichuk·Sabine Harribey
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Abstract

This paper studies generic surface defects for multiscalar critical models using a perturbative $\epsilon$ expansion in $4-\epsilon$ dimensions. The beta functions of the defect couplings for a generic multiscalar bulk with quartic interactions are computed at first non-trivial order in $\epsilon$. Specific bulks of interest are then considered: $O(N)$, hypercubic, hypertetrahdral, and biconical $O(m)\times O(n)$. In each case, we compute fixed points for the defect couplings and determine the remaining bulk symmetry. Expanding beyond the $O(N)$ model, we find a greater variety of patterns of symmetry breaking.

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Andrii Anataichuk, Sabine Harribey. 2025-03-07. Note on surface defects in multiscalar critical models. https://doi.org/10.1088/1751-8121%2Fadf26d

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