ideas-physics-cheapQuantumComputing

It's possible that what state collapse is really about is information, that is, what each observer can know. 'Quantum erasure' ( http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser ) experiments seem to show that if you lose access to information, that can cause state to 'un-collapse'.

It may be that quantum decoherence is a discretizing event that happens when some continuous quantity (i'm betting it has to do with the maximal possible information content of the observers) gets too large (sorta like the transition from subsymbolic to symbolic thought.. interesting connection there).

Even a small amout of leakage of information into the environment can cause quantum decoherence, even if the leaked information gets so scrambled up that we humans have little chance of ever unscrambling it. Perhaps this is the universe's way of provably ensuring consistency in observed outcomes.

So, the idea: quantum erasure shows there are types of information erasure that the universe accepts as having 'erased enough' and the difficulty of keeping conventional qubits from decohering show that there are other types of information erasure that seem to scramble the information from a human perspective but aren't good enough for the universe.

The question is, can we find some innovative way of scrambling information in such a way that (a) it is good enough for the universe, but (b) it doesn't require expensive equipment?

One approach is to try and rely on mathematics rather than physics to drive the scrambling. IF quantum decoherence is really based on some continuous quantity of 'usable information', then perhaps we can find a way to keep that quantity small without actually physically isolating anything, perhaps using chaotic systems.