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Lattice Evidence that Scalar Glueballs Are Small

Ryan Abbott1, Daniel C. Hackett2, Dimitra A. Pefkou3,4,*, Fernando Romero-López5, and Phiala E. Shanahan1

  • *Contact author: dpefkou@berkeley.edu
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Phys. Rev. Lett. 136, 041901 – Published 26 January, 2026

DOI: https://doi.org/10.1103/67xg-qxhz

Abstract

This Letter 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.

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Phys. Rev. Lett. 136, 041901– Published 26 January, 2026
  • Received 12 September 2025
  • Revised 21 November 2025
  • Accepted 3 December 2025
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