Fragmentation and defragmentation of strings in type IIA and their holographic duals

TL;DR

This paper investigates how long operators in various supersymmetric conformal field theories are represented by folded string configurations in type IIA geometries, revealing fragmentation phenomena and new dispersion relations at strong coupling.

Contribution

It introduces a novel analysis of string fragmentation and dispersion relations in type IIA duals of SCFTs, connecting semiclassical string dynamics to operator behavior.

Findings

Identification of string fragmentation near flavor D6 branes.

Discovery of new dispersion relations in 6d and 4d SCFTs.

Connection between string configurations and operator dynamics in dual field theories.

Abstract

We probe type IIA geometries with \emph{folded} semiclassical strings those encode the strong coupling dynamics associated with long operators in a class of SCFTs pertaining to spacetimes whose dimension vary from $6d$ down to $2d$. We particularly focus on folded string configurations those are extended through stack of flavor $ Dp $ ($ p=6,8 $) branes localized along the internal manifold. Considering some specific examples within the realm of $ \mathcal{N}=2 $ linear quivers, we show that the associated string spectrum exhibits a pole as the string approaches flavor D6 branes. We identify this as a \emph{fragmentation} of long operators in the dual $ \mathcal{N}=2 $ SCFTs. On the other hand, a similar analysis for $ \mathcal{N}=(1,0) $ SCFTs in $6d$ as well as $ \mathcal{N}=(0,4) $ SCFTs in $ 4d $ reveals a set of new dispersion relations at strong coupling. Based on semiclassical calculations, we set an argument that explains either of these cases.