A team of scientists is proposing a bold alternative to the Big Bang theory, suggesting that our universe may have formed inside a colossal black hole residing in a larger, parent universe. The Big Bang theory, along with Einstein’s general relativity, has successfully explained major cosmological phenomena, including the cosmic microwave background, the universe’s large-scale structure, and its accelerating expansion often linked to dark energy.
It depends on what is meant by “absolute” and “beginning”. It’s possible the Big Bang stretches “backward”, which is known as the “no boundary proposal”.