Fermionic Zero Mode and String Creation between D4-Branes at Angles

TL;DR

This paper investigates string creation between angled D4-branes in string theory, revealing that fermionic zero modes cause the effective potential to become angle-independent under partial supersymmetry, indicating string formation.

Contribution

It demonstrates that fermionic zero modes lead to angle-independent potentials and string creation between D4-branes at angles, confirmed through multiple approaches.

Findings

Fermionic zero modes change the sign of the one-loop potential.

Effective potential becomes angle-independent under partial supersymmetry.

String creation is confirmed via tension calculations from deformed Chern-Simons terms.

Abstract

We study the creation of a fundamental string between D4-branes at angles in string theory. It is shown that $R(-1)^{F}$ part of the one-loop potential of open string changes its sign due to the change of fermionic zero-mode vacua when the branes cross each other. As a result the effective potential is independent of the angles when supersymmetry is partially unbroken, and leads to a consistent picture that a fundamental string is created in the process. We also discuss the s-rule in the configuration. The same result is obtained from the one-loop potential for the orthogonal D4-branes with non-zero field strength. The result is also confirmed from the tension obtained by deforming the Chern-Simons term on one D4-brane, which is induced by another tilted D4-brane.