Type IIB instanton as a wave in twelve dimensions

TL;DR

This paper proposes that the type IIB D-instanton can be understood as a wave in twelve dimensions, extending the analogy of 11-dimensional gravitational waves to IIB string theory.

Contribution

It introduces a novel interpretation of the D-instanton as a reduction of a 12-dimensional wave, linking instanton charge to linear momentum in higher dimensions.

Findings

D-instanton viewed as a 12D wave reduction

Instanton charge related to 12D linear momentum

Suggests a fundamental role for instantons in IIB theory

Abstract

0-brane of type IIA string theory can be interpreted as a dimensional reduction of a gravitational wave in 11 dimensions. We observe that a similar interpretation applies also to the D-instanton background of type IIB theory: it can be viewed as a reduction (along one spatial and one time-like direction) of a wave in a 12-dimensional theory. The instanton charge is thus related to a linear momentum in 12 dimensions. This suggests that the instanton should play as important role in type IIB theory as the 0-brane is supposed to play in type IIA theory.