A five-dimensional effective model for excited light mesons

TL;DR

This paper introduces a novel five-dimensional holographic model for excited light mesons, where the spectrum arises from scalar field coupling related to gluon condensates, showing Regge-like behavior.

Contribution

It proposes an alternative 5D holographic model for mesons based on scalar field condensation linked to gluon condensates, differing from traditional background-based approaches.

Findings

Spectrum includes finite discrete states and continuum

Model exhibits Regge-like behavior in strong coupling

Suggests a connection to QCD scale anomaly

Abstract

In the usual holographic approach to QCD, the meson spectrum is generated due to a non-trivial 5-dimensional background. We propose an alternative 5-dimensional scenario in which the spectrum emerges due to coupling to a scalar field whose condensation is supposed to be dual to the formation of gluon condensate and mimics the scale anomaly in QCD. The spectrum of model has finite number of discrete states plus continuum and reveals a Regge-like behavior in the strong coupling regime.