How does the expansion rate relate to the age of the universe?

The correct answer highlights a fundamental aspect of cosmology: the relationship between the rate of expansion of the universe and its age. When the universe expands rapidly, it suggests that it has not had the time to develop and grow into a much older universe. This is often conceptualized with the model of the Big Bang, which states that the universe has been expanding since its inception.

If the universe is expanding at a faster rate, it typically indicates that the universe is still in a relatively young phase. A faster expansion means that galaxies are moving away from each other more quickly, reflecting a shorter time since the initial expansion event. Conversely, if the rate of expansion were slower, it would imply that the universe has had more time to age and evolve, leading to a possibility of a greater age.

This relationship is reinforced by models of cosmic expansion, particularly those including dark energy which influences the acceleration of the universe's overall expansion rate. In more stable and slower expanding scenarios, the universe has the opportunity to form structures, stars, and galaxies, which suggests a greater age of cosmological development. Thus, understanding this link is crucial in cosmology, shaping our perception of the universe's timeline and evolution.