There's a handful of cosmologists and QM types who claim "the universe computes". There's another crowd who insist this is rubbish - the universe isn't a computer. However, it certainly appears to be 'computational'; this is demonstrable: if we can write a program that simulates a real physical process (the gas laws, say), and do this for all of the processes we know about (so all the simulations then prove that we do know, if they exactly reproduce these processes in "computer-space", i.e. virtually), then a simulation of the known universe exists. If there is no actual physical computation (the universe we simulate is only our imaginary version of whatever it really is) then we should be able to write a program that demonstrates 'no physical computation exists', using a real physical computer, since the computer (we use to write the simulation) really isn't physical... See where this is going? Alternately, we should be able to write a program (on a real/imaginary computer) that proves "no computation occurs, the universe does not compute, it isn't computational". So why haven't we?