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Question of the Month

What Is Time?

Each answer below receives a book. Apologies to the many entrants not included.

“Time does not exist without change,” said Aristotle. Until recently, most physicists and cosmologists agreed with him. Recently, however, another argument is being offered: time needs to exist for change to happen. This means time must have existed before the Big Bang, since something, however small, had to change to ignite it. The relationship between time and gravity is, I believe, the key to the origin of the universe.