Physicists finally calculated where the proton’s mass comes from

Only 9 percent of the subatomic particle’s bulk comes from the mass of its quarks

an illustration of protons in the nucleus of an atom

MASSIVE UNDERTAKING  Using a technique called lattice QCD, scientists figured out how protons (illustrated here in the nucleus of an atom) get their mass.

ktsdesign/Shutterstock

A proton’s mass is more than just the sum of its parts.