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arXiv · 2508.21821

Lattice evidence that scalar glueballs are small

Ryan Abbott·Daniel C. Hackett·Dimitra A. Pefkou·Fernando Romero-López·Phiala E. Shanahan
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Abstract

This work reports the first calculation of the gravitational form factors (GFFs) of the scalar glueball, performed via lattice field theory in Yang-Mills theory at a single lattice spacing. The glueball GFFs are compared with those of other hadrons as determined in previous lattice calculations, providing strong indications that glueballs have a different gluonic structure than typical hadronic states. A mass radius of 0.263(31) fm is predicted, supporting previous suggestions that the scalar glueball is significantly smaller than other hadrons. These results point towards a potential smoking-gun characteristic to target by experimental glueball searches.

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Ryan Abbott, Daniel C. Hackett, Dimitra A. Pefkou, Fernando Romero-López, Phiala E. Shanahan. 2025-08-29. Lattice evidence that scalar glueballs are small. https://arxiv.org/abs/2508.21821

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