", he became convinced of something he came to call the Dust Theory, which holds that there is no difference, even in principle, between physics and mathematics, and that all mathematically possible structures exist, among them our physics and therefore our spacetime. These structures are being computed, in the manner of a program on a universal Turing machine, using something Durham refers to as "dust" which is a generic, vague term describing anything which can be interpreted to represent information; and therefore, that the only thing that matters is that a mathematical structure be self-consistent and, as such, computable. As long as a mathematical structure is possibly computable, then it is being computed on some dust, though it does not matter what dust actually is, only that there be a possible interpretation where such a computation is taking place somehow. The dust theory implies, as such, that all possible universes exist and are equally real, emerging spontaneously from their own mathematical self-consistency."

Great book!