Which event in the history of the universe happened last?
A) The electroweak force separated into electromagnetic and weak nuclear forces.
B) Stable helium nuclei formed.
C) Neutral atoms formed.
D) The GUT force separated into the electroweak force and strong force.

Question

Quizplus · Accepted Answer

Neutral atoms formed after the universe cooled down enough for electrons to combine with nuclei, allowing light to travel freely for the first time in cosmic history. This happened about 380,000 years after the Big Bang. The other events listed happened earlier in the history of the universe.

Which Event in the History of the Universe Happened Last