Coulomb branch Hilbert series and Hall-Littlewood polynomials
Stefano Cremonesi, Amihay Hanany, Noppadol Mekareeya, Alberto Zaffaroni
TL;DR
This work develops a robust framework for Coulomb branch Hilbert series in 3d ${\cal N}=4$ theories by incorporating background magnetic fluxes for flavor symmetries, enabling gluing of building blocks to construct more general theories. It proves a Hall-Littlewood formula for the Coulomb branch Hilbert series of $T_{\bm{\rho}}(G)$ (with $G$ classical) and demonstrates that these branches are complete intersections when background fluxes vanish; mirror symmetry is shown to map fluxes to baryonic charges on the Higgs branch. The results unify monopole-based and Hall-Littlewood approaches across $SU(N)$, $SO(N)$, and $USp(2N)$ families, provide explicit quiver constructions and partition classifications, and reveal analytic structures where moving a box in the partition generates new theories via residues. Collectively, these insights offer a versatile toolkit for computing and interpreting Coulomb branch moduli spaces, with implications for dualities and gluing constructions in 3d ${\cal N}=4$ theories.
Abstract
There has been a recent progress in understanding the chiral ring of 3d $\mathcal{N}=4$ superconformal gauge theories by explicitly constructing an exact generating function (Hilbert series) counting BPS operators on the Coulomb branch. In this paper we introduce Coulomb branch Hilbert series in the presence of background magnetic charges for flavor symmetries, which are useful for computing the Hilbert series of more general theories through gluing techniques. We find a simple formula of the Hilbert series with background magnetic charges for $T_ρ(G)$ theories in terms of Hall-Littlewood polynomials. Here $G$ is a classical group and $ρ$ is a certain partition related to the dual group of $G$. The Hilbert series for vanishing background magnetic charges show that Coulomb branches of $T_ρ(G)$ theories are complete intersections. We also demonstrate that mirror symmetry maps background magnetic charges to baryonic charges.
