Do We Live in a Multiverse?
As far as we currently know, there is a single expanding blob of spacetime speckled with trillions of galaxies - that's our Universe. If there are others, we have no compelling evidence for their existence. That said, theories of cosmology, quantum physics, and the very philosophy of science have a few problems that could be solved if our blob of 'everything' wasn't, well, everything. That doesn't mean other universes must exist. But what if they do? What is a universe? It should be a simple question to answer. But different areas of science will have subtly different takes on what a universe even is. Cosmologists might say it describes the total mass of stuff (and the space in between) that has been slowly expanding from a highly concentrated volume over the past 13.77 billion years, becoming increasingly disordered with age. It now stretches 93 billion light years from edge to edge, at least based on all of the visible (and invisible) stuff we can