According to the standard model,
A)the four forces of nature existed from the moment of the Big Bang.
B)energy in the form of radiation still dominates in the universe.
C)the four forces of nature were initially unified into a single force.
D)stable atomic nuclei formed in less than 0.01 s.
E)the universe was initially very cold and dense.

Question

Quizplus · Accepted Answer

The Standard Model proposes that the four fundamental forces of nature (gravity, electromagnetism, strong and weak nuclear forces) were initially unified into a single unified force during the early moments of the universe, at temperatures above 10^15 K.

Answer: D
 According to the Standard Model, stable atomic nuclei formed within the first three minutes of the universe, during a phase known as Big Bang nucleosynthesis. This took place when the temperature cooled down to about 10^9 K, which allowed protons and neutrons to combine to form stable atomic nuclei.

Therefore, the best choices are C and D.