Physical Number: numbers for counting (O(n)) Unphysical Number: numbers of possibilities (O(2^n))
The only difference between classical computing and quantum computing (Q.C.) is "Rotate-Compute-Rotate"
Contrary to myth, quantum computers are not known to be able to solve efficiently the very hard class called NP-complete problems.
There are two good Q.C. courses on Youtube:
Quantum Information Processing Conference: Here
An a fun video to actually see light as wave: Here
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