The Big Bang describes how the Universe began as a single point 13.7 billion years ago, and has been expanding ever since, but it doesn’t explain what happened before that. Researchers from Penn State University believe that there should be traces of evidence in our current universe that could used to look back before the Big Bang. According to their research, there was a contracting universe with similar space-time geometry to our expanding universe. The universe collapsed and then “bounced” as the Big Bang.
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