What is the name of the period of rapid expansion shortly after the Big Bang?
a) The Stellar Era b) The Inflationary Era c) The Dark Age d) The Reionization Era?
The correct answer and explanation is:
The correct answer is b) The Inflationary Era.
The Inflationary Era refers to a period of rapid expansion in the early universe, shortly after the Big Bang. This phase occurred within the first fraction of a second (roughly 10^-36 to 10^-32 seconds after the Big Bang). During this period, the universe expanded at an exponential rate, far faster than the speed of light. The idea of cosmic inflation was proposed by physicist Alan Guth in the early 1980s to address some unresolved issues in the Big Bang model, such as the horizon problem and the flatness problem.
The inflationary model suggests that the universe was once contained in a tiny, extremely hot, and dense state. Within a very short time, this minuscule region underwent a dramatic expansion, growing by a factor of at least 10^26 in just a fraction of a second. This rapid expansion smoothed out any irregularities and led to the uniform universe we observe today.
After inflation, the universe continued to expand but at a slower rate, cooling down as it did. The energy from inflation transformed into particles and radiation, and the universe began to take its familiar form.
This rapid expansion also provided an explanation for the uniformity of the cosmic microwave background radiation, which is the afterglow of the Big Bang. The inflationary model helps to explain why distant parts of the universe appear to have similar properties, even though they should not have been in contact with each other due to the finite speed of light.
The other eras mentioned in the question—the Dark Age, Stellar Era, and Reionization Era—occurred much later in the universe’s history, after inflation had already taken place.