[JimmyRuska]

Sounds like it's just a Haskell thunk but as a probability wave

Lazily evaluated until there's a probability it has to interact with something. Since you can never really see the value of the actual function, but only see what it looks like when it's forced to evaluate a computation in some context, an interaction, you can never get a precise definition of the function

[canjobear]

The difference is that these thunks can interfere and get entangled with each other.

[yazzku]

Control.Monad.Random