The Big Bang: not an explosion, but the birth of space and time

The article explains that the Big Bang was not a violent explosion but the starting expansion of the universe, which has been growing for about 13.8 billion years. Evidence from galaxies moving apart and the Cosmic Microwave Background supports this view. Importantly, there was no space or time before the Big Bang, so asking what happened “before” is tricky. The universe’s expansion continues today and is accelerating, a behavior tied to dark energy though its nature remains not well understood.