https://doi.org/10.1140/epja/s10050-025-01557-x
Regular Article - Theoretical Physics
Nucleon gravitational form factors
1
Dpto. Ciencias Integradas, Centro de Estudios Avanzados en Fis., Mat. y Comp., Fac. Ciencias Experimentales, Universidad de Huelva, 21071, Huelva, Spain
2
Dpto. Sistemas Físicos, Químicos y Naturales, Univ., Pablo de Olavide, 41013, Sevilla, Spain
3
European Centre for Theoretical Studies in Nuclear Physics and Related Areas (ECT*), Villa Tambosi, Strada delle Tabarelle 286, 38123, Villazzano, TN, Italy
4
School of Physics, Nanjing University, 210093, Nanjing, Jiangsu, China
5
Institute for Nonperturbative Physics, Nanjing University, 210093, Nanjing, Jiangsu, China
6
Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany
7
Technische Universität Dresden, 01062, Dresden, Germany
Received:
2
April
2025
Accepted:
4
April
2025
Published online:
2
May
2025
A symmetry-preserving analysis of strong interaction quantum field equations is used to complete a unified treatment of pion, kaon, and nucleon electromagnetic and gravitational form factors. Findings include a demonstration that the pion near-core pressure is roughly twice that in the proton, so both are significantly greater than that of a neutron star; parton species separations of the nucleon’s three gravitational form factors, in which, inter alia, the glue-to-quark ratio for each form factor is seen to take the same constant value, independent of momentum transfer; and a determination of proton radii orderings, with the mechanical (normal force) radius being less than the mass-energy radius, which is less than the proton charge radius. This body of predictions should prove useful in an era of experiments that will enable them to be tested.
© The Author(s) 2025
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