Describe a quantum computer
I would like to know if the following counterintuitive statement is representative for how a supposed quantum computer is believed to posses an exponential speed up over modern modern computers:
Define a $\displaystyle 1 qubit$ system as one machine, a $\displaystyle 2 qubit$ system as two machines, and so on.
If one machine can accomplish a task in 64 minutes, then 2 machines can accomplish the task in 16 minutes, while 3 machines can accomplish it in 8 minutes, while 4 machines in only 4 minutes.
