Which of the following observations cannot be explained by the Big Bang theory unless we assume that an episode of inflation occurred?
A)the fact that the temperature of the cosmic microwave background is almost the same everywhere
B)the fact that about 25% of the ordinary matter in the universe consists of helium
C)the existence of the cosmic microwave background
D)the fact that the universe is expanding

Question

Quizplus · Accepted Answer

The Big Bang theory predicts that regions of the universe that have never been in contact with each other should have different temperatures. However, observations show that the cosmic microwave background has an almost uniform temperature. Inflation provides a possible explanation for the uniformity of the cosmic microwave background by suggesting that the entire observable universe was once in contact and then rapidly expanded.

Which of the Following Observations Cannot Be Explained by the Big