Any useful applications at all?

Agerhell

Are there any applications at all so far depending on the so-called Copenhagen interpretation?

By this I mean superposition of states that could be used in "quantum computers", quantum entanglement or "one-photon encryption". Or are there any applications coming up in the near future on any of this?

I am just asking because when I went to university some ten years ago we spend some time on fantasizing on such things.

Sure you have atomic clocks and stuff, but these are not based on the stranger part of quantum mechanics...

Ken G

I don't think we are very close to any applications in which differences in the interpretations make any difference to predicted outcomes. Hence, the interpretations are still just interpretations of a single theory, not separate theories. Some interpretations do seem to claim the presence of different theories that underlie quantum mechanics, and claim to make different predictions, but I've never seen any that seem likely to be tested in the near future. My guess is, by the time we can detect those kinds of differences, quantum mechanics itself will have been replaced-- perhaps by a theory that unifies it with gravity, perhaps by something that doesn't.