Defects in N=1 minimal models and RG flows
Matthias R. Gaberdiel, Lasse Merkens
TL;DR
The paper develops a defect-based framework to constrain RG flows among ${\cal N}=1$ superconformal minimal models, first using a bosonic SU(2) coset description of the subalgebra and then elevating the discussion to the full superconformal theory. By identifying defects that commute with the perturbations, it derives RG invariants from defect quantum dimensions and twisted Hilbert-space spin content, which must match between UV and IR. The main results yield explicit flow patterns ${\cal SM}(p,q)\to{\cal SM}(p,q')$ with $q'=sp-I$ (and their SUSY counterparts ${\cal SM}(p,sp+I)\to{\cal SM}(p,sp-I)$), along with the perturbing fields and preserved defect sets that implement these flows. The approach reproduces known unitary flows and provides a principled, extensible method for analyzing a broad class of ${\cal N}=1$ minimal models and potential generalizations to higher supersymmetry in string-theoretic contexts.
Abstract
Utilising the symmetry constraints of suitable topological defects, the possible RG flows of N=1 superconformal minimal models are studied. We first employ a coset description that only captures the bosonic subalgebra, and then generalise the discussion to the actual superconformal models.
