Moving Moduli, Calabi-Yau Phase Transitions and Massless BPS Configurations in Type II Superstrings

TL;DR

This paper explores how moduli of Calabi-Yau spaces in type II superstring compactifications vary over spacetime, leading to BPS black hole solutions that undergo topology-changing phase transitions with massless configurations.

Contribution

It provides a detailed analysis of phase transitions in Calabi-Yau moduli space within type II superstrings, linking geometric singularities to BPS solutions with zero mass.

Findings

Identifies conditions for topology change in Calabi-Yau moduli space.

Describes BPS configurations with zero ADM mass acting as domain walls.

Links singular loci to phase transitions in string compactifications.

Abstract

In this paper we discuss compactifications of type II superstrings where the moduli of the internal Calabi-Yau space vary over four-dimensional space time. The corresponding solutions of four-dimensional N=2 supergravity are given by charged, extremal BPS black hole configurations with non-constant scalar field values. In particular we investigate the behaviour of our solutions near those points in the Calabi-Yau moduli space where some internal cycles collapse and topology change (flop transitions, conifold transitions) can take place. The singular loci in the internal space are related to special points in the uncompactified space. The phase transition can happen either at spatial infinity (for positive charges) or on spheres (with at least one negative charge). The corresponding BPS configuration has zero ADM mass and can be regarded as a domain wall that separates topologically different vacua of the theory.