D-instanton Effects on a D3-brane

TL;DR

This paper uses open-closed string field theory to analyze D-instanton effects on a D3-brane in type IIB string theory, confirming some conjectures and challenging others about non-perturbative corrections to the effective action.

Contribution

It applies Sen's formalism to compute D-instanton corrections to the D3-brane effective action, providing new insights into multi-instanton effects and their agreement with existing conjectures.

Findings

One-instanton contribution matches Green and Gutperle's conjecture.

Multi-instanton contribution disagrees with the conjecture.

Provides explicit calculations of D-instanton effects on the $D^4 F^4$ coupling.

Abstract

It has been proposed by Sen that the D-instanton effects in string theory can be systematically determined through the framework of open-closed string field theory. We apply the latter formalism to analyze the D-instanton corrections to the quantum effective action of a D3-brane in type IIB superstring theory, and determine the leading single and multi-instanton contributions to the $D^4 F^4$ effective coupling which is unprotected by supersymmetry. Notably, while we find that the one-instanton contribution agrees with a conjecture of Green and Gutperle, the multi-instanton contribution disagrees with the conjecture.