Why is the fact that the cosmic background radiation (CBR)is very smooth considered a problem?
A) A universe as smooth as predicted by the CBR should not have formed as many galaxies as have been observed.
B) A universe as smooth as predicted by the CBR should have collapsed by now.
C) A universe as smooth as predicted by the CBR should be expanding much faster than we are now.
D) A universe as smooth as predicted by the CBR should never occur because quantum mechanical fluctuations would have been imprinted on it.

Question

Quizplus · Accepted Answer

According to the theory of cosmic inflation, quantum mechanical fluctuations in the very early universe should have been imprinted on the CBR. The fact that the CBR is very smooth suggests that these fluctuations did not occur, which is a problem for the theory.

Why Is the Fact That the Cosmic Background Radiation (CBR)is