Gauged Linear Sigma Models for toroidal orbifold resolutions

TL;DR

This paper develops a GLSM framework to describe toroidal orbifolds and their resolutions, enabling analysis of topology changes and potential applications to string phenomenology.

Contribution

It introduces a global GLSM formalism for toroidal orbifolds, allowing unified study of orbifold singularities, resolutions, and moduli space transitions.

Findings

GLSM describes two-tori as hypersurfaces in weighted projective spaces

Orbifold singularities are resolved via non-compact toric resolutions in GLSM

Moduli space and topology changes are studied as phase transitions

Abstract

Toroidal orbifolds and their resolutions are described within the framework of (2,2) Gauged Linear Sigma Models (GLSMs). Our procedure describes two-tori as hypersurfaces in (weighted) projective spaces. The description is chosen such that the orbifold singularities correspond to the zeros of their homogeneous coordinates. The individual orbifold singularities are resolved using a GLSM guise of non-compact toric resolutions, i.e. replacing discrete orbifold actions by Abelian worldsheet gaugings. Given that we employ the same global coordinates for both the toroidal orbifold and its resolutions, our GLSM formalism confirms the gluing procedure on the level of divisors discussed by Lust et al. Using our global GLSM description we can study the moduli space of such toroidal orbifolds as a whole. In particular, changes in topology can be described as phase transitions of the underlying GLSM. Finally, we argue that certain partially resolvable GLSMs, in which a certain number of fixed points can never be resolved, might be useful for the study of mini-landscape orbifold MSSMs.