Sakharov's conditions are a set of criteria proposed by physicist Andrei Sakharov to explain the observed imbalance between matter and antimatter in the universe. He suggested that for a universe to have more matter than antimatter, three conditions must be met: baryon number violation, C and CP violation, and thermal equilibrium. These conditions imply that certain processes in the early universe could create an excess of baryons, the particles that make up matter. Sakharov's ideas have influenced modern cosmology and particle physics, guiding research into the fundamental forces and particles that shape our universe.