Tetrahedron instantons in Donaldson-Thomas theory

TL;DR

This paper introduces the moduli space of tetrahedron instantons within Donaldson-Thomas theory, constructs associated invariants, and relates their partition function to known DT invariants, providing new geometric insights.

Contribution

It defines the moduli space of tetrahedron instantons as a Quot scheme, constructs its virtual classes, and explicitly computes the partition function, connecting it to existing DT invariants.

Findings

Partition function matches the one studied by Pomoni-Yan-Zhang.

Explicitly expressed as a product of shifted rank-one DT invariants.

Provides geometric answers to questions about the moduli space and its invariants.

Abstract

Inspired by the work of Pomoni-Yan-Zhang in String Theory, we introduce the moduli space of tetrahedron instantons as a Quot scheme and describe it as a moduli space of quiver representations. We construct a virtual fundamental class and virtual structure sheaf \`a la Oh-Thomas, by which we define K-theoretic invariants. We show that the partition function of such invariants reproduces the one studied by Pomoni-Yan-Zhang, and explicitly determine it, as a product of shifted partition functions of rank one Donaldson-Thomas invariants of the three-dimensional affine space. Our geometric construction answers a series of questions of Pomoni-Yan-Zhang on the geometry of the moduli space of tetrahedron instantons and the behaviour of its partition function, and provides a new application of the recent work of Oh-Thomas.