A view of the colorful microcosm within a proton

The proton sounds like a simple object, but it's not. Inside, there's a teeming microcosm of quarks and gluons with properties such as spin and "color" charge that contribute to the particle's seemingly simplistic role as a building block of visible matter. By analyzing the particle debris emitted from collisions of polarized protons at the Relativistic Heavy Ion Collider (RHIC), scientists say they've found a new way to glimpse that internal microcosm. They've measured a key effect of the so-ca...