Re:Quantum teleportation over 143 kilometres using active fe...
by tgb on Sunday September 09, 2012 @11:55AM
(#4496057)
What silverdrake said, but also it's a matter of error-tolerance. If we want to do a difficult two-step computation and know when each sub-step succeeds or fails, than:
1) Perform the first step on a qubit (repeat if failed)
2) Your friend performs the second step on their qubit (repeat if failed, but no need to repeat (1))
3) Teleport your qubit to your friend
4) Your friend performs a simply operation on their qubit
After this, the state of your friend's qubit is now the result of applying both operations. But each sub-step can be redone without affecting the result of the other, so mistakes are easier to correct. So in this case, "your friend" might refer to yourself - the important part isn't teleporting the qubit somewhere elses, it's that the computation is less error-prone.
1) Perform the first step on a qubit (repeat if failed)
2) Your friend performs the second step on their qubit (repeat if failed, but no need to repeat (1))
3) Teleport your qubit to your friend
4) Your friend performs a simply operation on their qubit
After this, the state of your friend's qubit is now the result of applying both operations. But each sub-step can be redone without affecting the result of the other, so mistakes are easier to correct. So in this case, "your friend" might refer to yourself - the important part isn't teleporting the qubit somewhere elses, it's that the computation is less error-prone.