At about what time after the Big Bang did the universe pass through the transition from being radiation-dominated to being matter-dominated? A) at the Planck time, 10^-43 s B) about 15 billion years, as stars began to form C) 500,000 years D) 30,000 years

Question

Quizplus · Accepted Answer

The transition from a radiation-dominated universe to a matter-dominated universe occurred approximately 30,000 years after the Big Bang. This transition is significant because it marks the point at which the density of matter became greater than the density of radiation, leading to the formation of structures in the universe.

At About What Time After the Big Bang Did the Universe