Thread: Quantum Computers

Originally Posted by drewmandan

Actually the probability amplitudes are real numbers and are calculated as the mod-squared of the wavefunction, which is complex. /end nitpick

Are you sure? From my understanding, the value of the wavefunction (function that maps from a space representing the possible states of the system, to the complex numbers) at any particular point is the probability amplitude (complex), and squaring the modulus of that will give you the probability of the system being measured as being in that state (real). What you describe sounds like this value of probability. Call me on this if I am wrong, though, I'm no quantum physicist, just an interested amateur.

The biggest problem is that even if quantum chips are faster than regular ones, it doesn't really matter [because of current RAM speeds]

This is way off, as far as I know. Quantum computing doesn't rely on traditional RAM. You initialise the system, allow its components to interact, then measure some of them (like a regular computer, dohohoho). You might use traditional RAM to store input and output data, but it isn't going to significantly impact the speed of your quantum computation. You may need, however, some sort of quantum analogue to ordinary RAM, but the design of something like that would be very different to the design of RAM today.