In a universe with an accelerating expansion rate, the actual age of the universe is __________ the Hubble time.
A) larger than
B) smaller than
C) negligible compared to
D) the same as
E) independent of

Question

Quizplus · Accepted Answer

The Hubble time is defined as the inverse of the Hubble constant, which characterizes the rate at which the universe is expanding. In a universe with an accelerating expansion rate, the Hubble time will be smaller than the actual age of the universe. This is because the universe started expanding at a slower rate in the past, and has been accelerating in recent times. Therefore, the universe needed more time to reach its current size and age than what the Hubble time suggests.

In a Universe with an Accelerating Expansion Rate, the Actual