Geometric Transitions, Flops and Non-Kahler Manifolds: II

TL;DR

This paper explores geometric transitions in string theories, focusing on global versus local metrics, non-Kahler manifolds, and flux configurations, advancing understanding of dualities and smooth flops in M-theory.

Contribution

It provides new global descriptions of geometric transitions in type I/heterotic theories and analyzes non-Kahler metrics and fluxes in type IIA and M-theory contexts.

Findings

Global descriptions are more complex than local models.

Identification of fluxes enabling smooth flops in M-theory.

Analysis of non-Kahler metrics and orientifold actions.

Abstract

We continue our study of geometric transitions in type II and heterotic theories. In type IIB theory we discuss an F-theory setup which clarifies many of our earlier assumptions and allows us to study gravity duals of N = 1 gauge theories with arbitrary global symmetry group G. We also point out the subtle differences between global and local metrics, and show that in many cases the global descriptions are far more complicated than discussed earlier. We determine the full global description in type I/heterotic theory. In type IIA, our analysis gives rise to a local non-Kahler metric whose global description involves a particular orientifold action with gauge fluxes localised on branes. We are also able to identify the three form fields that allow for a smooth flop in the M-theory lift. We briefly discuss the issues of generalised complex structures in type IIB theory and possible half-twisted models in the heterotic duals of our type II models. In a companion paper we will present details on the topological aspects of these models.