$(0, 4)$ dualities
Pavel Putrov, Jaewon Song, Wenbin Yan
TL;DR
The paper develops a 2d ${\cal N}=(0,4)$ framework mirroring 4d class ${\cal S}$ dualities, showing that a wide class of quiver gauge theories flow to SCFTs whose spectra are organized by a 2d TQFT on a Riemann surface ${\cal C}$. It provides explicit index computations for SU(2) and SU(N) quivers, unveils a 2d analogue of the $T_N$ sector via ${\cal T}_N^{(0,4)}$ and Argyres–Seiberg-type dualities, and demonstrates LG dual descriptions and $(0,2)$/$(2,2)$ analogues of crossing symmetry. The results connect 2d SCFTs to higher-dimensional constructions, including compactifications of the 6d ${\cal N}=(2,0)$ theory on ${\mathbb{CP}}^1 \times {\cal C}$, and suggest a reduction of Vafa–Witten TQFT structure to 2d, with implications for non-Lagrangian Higgs branches (e.g., $E_6$) and duality webs. Overall, the work extends the class ${\cal S}$ paradigm to two dimensions, providing new exact results and a unifying TQFT interpretation for a broad family of ${\cal N}=(0,4)$ theories.
Abstract
We study a class of two-dimensional ${\cal N}=(0, 4)$ quiver gauge theories that flow to superconformal field theories. We find dualities for the superconformal field theories similar to the 4d ${\cal N}=2$ theories of class ${\cal S}$, labelled by a Riemann surface ${\cal C}$. The dual descriptions arise from various pair-of-pants decompositions, that involves an analog of the $T_N$ theory. Especially, we find the superconformal index of such theories can be written in terms of a topological field theory on ${\cal C}$. We interpret this class of SCFTs as the ones coming from compactifying 6d ${\cal N}=(2, 0)$ theory on $\mathbb{CP}^1 \times {\cal C}$
