Pomeron Interactions from the Einstein-Hilbert Action

TL;DR

This paper develops an effective theory for the Pomeron as a tensor glueball derived from the Einstein-Hilbert action, and compares predicted angular distributions with experimental data, finding good agreement for a specific glueball candidate.

Contribution

It introduces a novel effective theory linking the Pomeron to tensor glueballs via holographic models and Einstein-Hilbert action, and validates it against experimental angular distribution data.

Findings

Good agreement with CERN WA102 data for the $f_2(2300)$ tensor glueball candidate.

Other tensor states show different distributions, indicating they are not related to gravitational excitations.

The Pomeron is modeled as a tensor with a two-index polarization tensor derived from graviton interactions.

Abstract

Holographic models of QCD, collectively known as AdS/QCD, have been proven useful in deriving several properties of hadrons. One particular feature well reproduced by such models is the Regge trajectories, both for mesons and glueballs. We focus on scalar and tensor glueballs, and derive an effective theory for the Pomeron by analytic continuation along the leading trajectory from the tensor glueball. It then follows that the Pomeron, as the tensor glueball itself, should possess a two-index polarization tensor, inherited from the graviton. The three-graviton interaction is deduced from the Einstein-Hilbert action. Using this structure in the cross section of double-Pomeron production of the tensor glueball, we calculate certain angular distributions of production and compare them with those from the CERN WA102 experiment. We find that the agreement is very good for the $f_2(2300)$ tensor glueball candidate. At the same time, other tensor states -- such as $f_2(1270)$ and $f'_2(1520)$ -- have completely different distributions, which we interpret as consequence of the fact that they are not glueballs and thus, in our model, unrelated to the gravitational excitations, which are dual to spin-2 glueballs.