Or that the Big Bang at time zero consisted of mass-energy, and that spacetime is a property of mass-energy; coupled with the observation that from observation we conclude energy can neither be created or destroyed.
That hypothesis has the advantage that at least we know mass-energy exists. (As for the Improbability Drive, see Adams' Hitchhiker's Guide to the Galaxy. As for gods, see Hans Anderson's Fairy Tales.)
Oh, if it's said to exist independently of a physical brain, it's magic pure and simple!
Yes, let's.
Again, not only do we know that creative intelligence exists, we ALSO know that it has the unique capacity to originate truly novel complex information systems, such as those which space/time matter/energy ultimately boil down to.
This cannot be similarly demonstrated for spontaneous processes, which without any creative input, require an infinite regression of further spontaneous processes to determine their own.
Andre Linde, principle in modern inflationary theory, considers it feasible; that we could one day create our own universe, that there's nothing inherently stopping us from doing so... and that this may in fact be where our's came from; a product of creative intelligence from another 'universe'. Others have even toyed with the idea that it is our own creation, having reverse engineered our own universe entirely.
Just a couple of possible scenarios for ID, which may well involve a physical brain as we understand it, - how likely? impossible to say, but if it is only one in a trillion, that's still vastly better odds than blind fluke