Classical glueballs in non-Abelian Born-Infeld theory

TL;DR

This paper demonstrates that a Born-Infeld modification of Yang-Mills theory allows for classical glueball solutions, which are absent in standard Yang-Mills theory, due to scale invariance breaking.

Contribution

It introduces a Born-Infeld-type non-linearity into Yang-Mills theory, enabling classical glueball solutions similar to gravitational sphalerons.

Findings

Classical glueballs exist in the modified theory.

Solutions resemble Bartnik-McKinnon configurations.

Scale invariance breaking is key to solution existence.

Abstract

It is shown that the Born-Infeld-type modification of the quadratic Yang-Mills action suggested by the superstring theory gives rise to classical particle-like solutions prohibited in the standard Yang-Mills theory. This becomes possible due to the scale invariance breaking by the Born-Infeld non-linearity. New classical glueballs are sphaleronic in nature and exhibit a striking similarity with the Bartnik-McKinnon solutions of the Yang-Mills theory coupled to gravity.