Rank-one 4d π©=3 SCFTs: Schur index, VOA modules, and modularity
Abstract
We study the representation theory of the vertex operator algebras (VOAs) associated with rank-one 4d π© = 3 superconformal field theories. For the β€3 S-fold theory, whose VOA π²β€3 has central charge c2d = β15, we use the π© = 1 Lagrangian description to obtain the unflavored Schur index in terms of Dedekind eta functions, while Wilson-loop indices yield the unflavored non-vacuum characters. These characters all solve a modular linear differential equation (MLDE) whose solution space also contains a logarithmic character. Combining flavored MLDEs from null states with Zhu's associative algebra and a free-field realization, we study four highest-weight modules of π²β€3 and their flavored characters in closed form. A parallel analysis applies to the π© = 3 theories obtained by gauging a discrete β€n flavor subgroup of π© = 4 U(1) and SU(2) super-Yang--Mills, for which we also obtain closed-form Schur indices and a new free-field realization of the VOA of the β€4 quotient.
Related
- Crossed modularity of twisted VOA modules
- On the modularity of residually reducible Galois representations of rank 2
- Construction of holomorphic SCFTs with minimal index
- Rank-two Nahm sums, modularity obstructions, and the McKay--Thompson series T31A
- simple cartan-free modules of finite rank over the super-virasoro algebras
BibTeX
@misc{guo2026rankone,
title = {{Rank-one 4d $\mathcal N=3$ SCFTs: Schur index, VOA modules, and modularity}},
author = {Zhaoting Guo and Satoshi Nawata and Yiwen Pan and Qituan Zhang},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.10685},
eprint = {2609.10685},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.10685},
}
RIS
TY - UNPB
TI - Rank-one 4d π©=3 SCFTs: Schur index, VOA modules, and modularity
AU - Zhaoting Guo
AU - Satoshi Nawata
AU - Yiwen Pan
AU - Qituan Zhang
PY - 2026
DA - 2026/09/09
PB - arXiv
DO - 10.48550/arxiv.2609.10685
UR - https://arxiv.org/abs/2609.10685
AB - We study the representation theory of the vertex operator algebras (VOAs) associated with rank-one 4d π© = 3 superconformal field theories. For the β€_3 S-fold theory, whose VOA π²_β€_3 has central charge c_2d = β15, we use the π© = 1 Lagrangian description to obtain the unflavored Schur index in terms of Dedekind eta functions, while Wilson-loop indices yield the unflavored non-vacuum characters. These characters all solve a modular linear differential equation (MLDE) whose solution space also contains a logarithmic character. Combining flavored MLDEs from null states with Zhu's associative algebra and a free-field realization, we study four highest-weight modules of π²_β€_3 and their flavored characters in closed form. A parallel analysis applies to the π© = 3 theories obtained by gauging a discrete β€_n flavor subgroup of π© = 4 U(1) and SU(2) super-Yang--Mills, for which we also obtain closed-form Schur indices and a new free-field realization of the VOA of the β€_4 quotient.
ER -