Answer
In 1+1 dimensions, Julian Schwinger demonstrated the phenomenon of confinement, where quarks are confined within hadrons and cannot be isolated individually. This confinement is a fundamental property of Quantum Chromodynamics (QCD), Theory describing the strong nuclear force between quarks and gluons. Schwinger's work laid the groundwork for our understanding of how quarks behave within hadrons and provided insights into the nature of strong interactions.