Bezerk's original comment makes two assumptions. 1) continuum phenomena are real and space is not merely quantized at a level which is undetectable by experiment (just because physics models it as a continuum doesn't mean it is so) 2) all of this precision actually makes a difference For instance, at the level of brain chemistry, who cares about quantum precision when thermal noises will swamp it anyway? (the Penrose argument even goes as far as assuming quantum gravity, a force pitifully weak, as a signficant factor) One of the reasons digital manipulation became popular was because analog data was too prone to error. Why will a quantum computer, which seems even more sensitive to external perturbation, be any different? And regardless of whether quantum computers work or not, they are still algorithmic if they can be simulated (however slowly) by a turing machine. It's a rigorous mathematical definition. Claiming otherwise uses algorithm in a manner different than was intended. It's like the way Ludwig Plutonium solves all those famous problems in sci.math by assuming different definitions of primality, etc. Quantum computers might be faster than classical computers, but non-algorithmic, I don't think so.