story
This is a common problem when we appeal to continuous natural phenomena, as their common description is usually a convenient, but imprecise, abstraction. Goldreich addressed this in On the philosophical basis of computational theories [1]: "A computational model cannot be justified by merely asserting that it is consistent with some theory of natural phenomena ... The source of trouble is the implicit postulate that asserts that whatever is not forbidden explicitly by the relevant electrical theories, can actually be implemented"[2]
[1]: http://www.wisdom.weizmann.ac.il/~oded/VO/qc-fable.pdf
[2]: He adds "at no cost" because his focus is complexity, not computability