Multi-spin string solutions in AdS Black Hole and confining backgrounds

TL;DR

This paper explores semi-classical multi-spin string solutions in non-supersymmetric backgrounds like AdS Black Hole and confining models, revealing conditions for existence, stability, and behavior of strings with various rotations.

Contribution

It provides new solutions for multi-spin strings in non-supersymmetric backgrounds and analyzes their stability and energy behavior, extending understanding beyond AdS space.

Findings

Solutions exist only with non-zero spin in the Black Hole background.

Strings can have regular large energy expansions without rotation in S^5.

Strings must be located on the confining wall in near-extremal D3 and D4 backgrounds.

Abstract

We study semi-classical multi-spin strings in the non-supersymmetric backgrounds of $AdS$ Black Hole and Witten's confining model. We consider constant radius strings with rotations along the isometries of the backgrounds. In the $AdS$ Black Hole, solutions exist only if there is a non-zero spin in the Black Hole part. In contrast with the $AdS$ background, we find solutions which although have no rotation in the $S^5$ part, have a regular $\lambda$ expansion in the expression for large energy. In the near-extremal $D_3$ and $D_4$ backgrounds, we find that strings have to be located on the confining wall. We also discuss the stability of solutions by considering the fluctuation Lagrangians.