"For centuries scientists believed that the universe always existed, it was eternal, it was always there. But thanks to persuasive, philosophical arguments and scientific discoveries just over the last several decades virtually all scientists are now convinced that the universe had a beginning at some point in the distant past," [Strobel] said. "And even though alternative models of the universe have been proposed, the Borde-Guth-Vikenkin Theorem tells us that any universe that is expanding, on average, thru its history, like ours, must have space-time boundary in the past. In other words, it must have had a beginning at some point."
According to Strobel, one of the scientists that formulated the theorem, physicist Alexander Vilenkin, who is the director Institute of Cosmology at Tufts University, said, "With the proof now in place, cosmologists can no longer hide behind the possibility of a past-eternal universe. There is no escape. They have to face the problem of a cosmic beginning."
He then addressed the issue of why there might be a problem for some scientists trying to accept a "beginning to the universe."
"Well, you know what? It's only a problem if you are an atheist, because if there is a beginning to the universe it leads to a very powerful argument for existence of God. It's called the Kalam Cosmological Argument," Strobel explained. "It's very easy, it only takes three steps. First, whatever begins to exist has a cause.
"Can you come up with an example of anything that began to exist that doesn't have cause? Even David Hume, the famous skeptic said, 'I never asserted so absurd a proposition as that anything might arise without a cause.'"
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