The theory that is. From Nature on our parent 4-D “bulk universe” and the 4-D star that underwent gravitational collapse, formed a 4-D black hole, with a 3-D, brane, event horizon that is actually our universe. Nature story here. Orignal arXiv paper here.
There’s a discrepancy though: the microwave background data from telescopes matches the classical Big Bang theory. Still, the new theory is only off by 4%. And it’s intuitively attractive.