The central heat trace on large compact classical groups
Thibaut Lemoine, Mylène Maïda
TL;DR
The paper proves a comprehensive large-$N$ expansion for the central heat trace on all compact classical groups, providing explicit coefficients that depend on the group type and revealing a parity structure: even powers for unitary cases and all powers for orthogonal/symplectic cases. It develops a random-partition framework and a highest-weights-to-partitions dictionary to derive the asymptotics, then translates the results into random-surface representations via Hurwitz spaces and into a Gromov–Witten picture on the torus. Two gauge/string dualities follow: a Yang–Mills/Hurwitz duality that expresses YM observables in terms of ramified coverings, and a Yang–Mills/Gromov–Witten duality that links YM data to GW invariants on elliptic curves, with coefficients given by derivatives of GW-generated functions. The work thus provides a rigorous bridge between 2D YM theory and both Hurwitz theory and GW theory, yielding explicit, computable formulas for the asymptotic expansion coefficients and clarifying the role of group-type couplings and chirality in the dualities.
Abstract
We establish the large-$N$ asymptotic expansion of the (central) trace of the heat kernel on any compact classical group $G_N\subset\mathrm{GL}_N(\mathbb{C})$, which extends a previous result known only for $\mathrm{U}(N)$ \cite{LM2}. It admits two new interpretations of the trace: in terms of ramified coverings of the torus, and Gromov-Witten invariants on elliptic curves. These connections allow us to explore several aspects of the gauge/string duality in two dimensions: a Yang-Mills/Hurwitz duality, and Yang-Mills/Gromov-Witten duality.
