3D structure of hadrons and energy-momentum tensor

TL;DR

This paper reviews recent advances in understanding the three-dimensional internal structure of hadrons through their form factors, highlighting new insights into mass, spin, and pressure distributions derived from electromagnetic and gravitational form factors.

Contribution

It summarizes recent developments in interpreting hadronic form factors, especially gravitational ones, to reveal internal properties like mass, spin, and pressure distributions.

Findings

Gravitational form factors have been experimentally extracted recently.

Form factors provide insights into the internal pressure and energy distribution.

Electromagnetic form factors have long been measured, aiding structural understanding.

Abstract

The three-dimensional spatial structure of hadrons is encoded in their form factors. Via appropriate Fourier transform, the latter describe how charge, energy, linear and angular momentum, but also pressure are distributed inside these systems. Electromagnetic form factors of the nucleon have been measured for a long time, but it is only recently that some gravitational form factors have been extracted from experimental data, creating a great deal of enthusiasm in the hadronic community. Here we summarize some of the recent developments on the interpretation of these form factors, and provide a quick overview of what we can learn about the nucleon mass, spin and internal pressure.