What do pions and kaons look like under gravity?

Using light-front quantum mechanics, researchers calculated how pions and kaons respond to gravitational probes—essentially mapping their internal mass, pressure, and shear-force distributions. One gravitational form factor matched lattice QCD predictions; the other showed unexpected enhancement at low energies, pointing to subtle effects from quantum zero-modes. These mechanical snapshots let physicists see how quarks actually arrange themselves inside these fundamental particles.