Linear Dilatons, NS5-branes and Holography

TL;DR

The paper discusses how certain string theory vacua with linear dilaton backgrounds are holographically dual to lower-dimensional non-local theories, exemplified by NS5-branes and matrix models, enabling the study of their observables.

Contribution

It demonstrates the holographic duality for linear dilaton backgrounds, including NS5-branes and matrix models, and explores their observable correlations.

Findings

Holographic duality applies to linear dilaton vacua.

String theory near NS5-branes is dual to little string theory.

Matrix models provide a holographic description of 2D string theory.

Abstract

We argue that vacua of string theory which asymptote at weak coupling to linear dilaton backgrounds are holographic. The full string theory in such vacua is ``dual'' to a theory without gravity in fewer dimensions. The dual theory is generically not a local quantum field theory. Excitations of the string vacuum, which can be studied in the weak coupling region using worldsheet methods, give rise to observables in the dual theory. An interesting example is string theory in the near-horizon background of parallel NS5-branes, the CHS model, which is dual to the decoupled NS5-brane theory (``little string theory''). This duality can be used to study some of the observables in this theory and some of their correlation functions. Another interesting example is the ``old'' matrix model, which gives a holographic description of two dimensional string theory.