Locc

[meteor]

What are the Local operations and classical communication that i keep hearing about?
It arises in quantum teleporting. Though i know that to perform quantum teleporting you need a classical channel (a phone line, an e-mail, etc) and I guess that classical communication refers to that, I still don't get the thing about local operations. It seems to me that is the fact to manipulate jointly the state that you want to teleport with the particle that you have in your possession of the quantum channel, but I'd like a concrete definition. Care to explain?

[slyboy]

Local operations means that Alice and Bob may each do anything allowed by quantum mechanics to their subsystem, but nothing that requires an interaction between their subsystems. This includes things like:

- Unitary operations
- Measurements
- Throwing away some particles
- Bringing in a new particle in a known state

All these things turn out to be useful in some quantum information protocols.

You are right about the classical communication bit. Usually, it is used so that Alice and Bob can communicate measurement results to one another, or so that they can share some classical correlations.