Quantum Curves and D-Modules
Robbert Dijkgraaf, Lotte Hollands, Piotr Sułkowski
TL;DR
The paper develops a unified framework where chiral fermions on quantum curves, realized physically via I-branes with a B-field, are governed by holonomic ${\cal D}$-modules and noncommuting coordinates with $[x,y]=\lambda$. This approach yields a prescription to extract all-genus partition functions and invariants across diverse systems, including matrix models, $c=1$ string theory, and Seiberg-Witten geometries, by quantizing spectral curves and constructing associated fermionic states whose determinants reproduce KP/Toda tau-functions. It demonstrates concrete D-module realizations for double-scaled and Hermitian matrix models (recovering KdV and topological gravity), the $c=1$ string via two asymptotic patches and Fourier-type gluing, and dual Nekrasov-Okounkov partition functions from SW curves, all tied to topological string theory and its five-dimensional uplift. The framework reveals deep connections among matrix models, integrable hierarchies, topological strings, and gauge theories, and highlights both perturbative and nonperturbative facets, including Stokes phenomena and wall-crossing, with potential links to the geometric Langlands program and quantum field theory dualities.
Abstract
In this article we continue our study of chiral fermions on a quantum curve. This system is embedded in string theory as an I-brane configuration, which consists of D4 and D6-branes intersecting along a holomorphic curve in a complex surface, together with a B-field. Mathematically, it is described by a holonomic D-module. Here we focus on spectral curves, which play a prominent role in the theory of (quantum) integrable hierarchies. We show how to associate a quantum state to the I-brane system, and subsequently how to compute quantum invariants. As a first example, this yields an insightful formulation of (double scaled as well as general Hermitian) matrix models. Secondly, we formulate c=1 string theory in this language. Finally, our formalism elegantly reconstructs the complete dual Nekrasov-Okounkov partition function from a quantum Seiberg-Witten curve.
