Spacetime Singularities in String and its Low Dimensional Effective Theory

TL;DR

This paper investigates how spacetime singularities behave under dimensional reduction and lifting in string theory and its effective theories, revealing that singularities can appear or disappear depending on the specific solutions and dimensions involved.

Contribution

It provides a detailed analysis of the conditions under which singularities are preserved or resolved when transitioning between string theory and its low-dimensional effective theories.

Findings

Singularities may or may not persist after lifting to higher dimensions.

Different solutions can have singularities on different surfaces across dimensions.

The behavior of singularities depends on the specific solution and dimensional context.

Abstract

Spacetime singularities are studied in both the $D+d$-dimensional string theory and its $D$-dimensional effective theory, obtained by the Kaluza-Klein compactification. It is found that spacetime singularities in the low dimensional effective theory may or may not remain after lifted to the $D+d$-dimensional string theory, depending on particular solutions. It is also found that there exist cases in which spacetime singularities appearing in high/low dimensional spacetimes do not necessarily happen on the same surfaces.