As far as I know that QM is probability-based and Feynman proposed a quantum computer (QC) as an emulator for fast computation. Reading the introductory articles, I just do not get the essence of the speedup. I understand the q-bits and such but basically, what is the idea?
Does Feynman simply mean that instead of computing the function of how something behaves (the frequency of oscillations for instance) from a complex model we just build the model physically and observe the behaviour? I see that even simple probabilistic problems may produce involved computations. Marginally more complex problem (its model) can demand prohibitively more complex computation. Does QC just builds a physical model and replaces the computation with measurement?