Reversing quantum measurement and information transfer

S W Lee (Seoul National University)

Quantum measurement lies at the heart of quantum mechanics both in fundamental issues and for 
applications. The general belief in its irreversibility has been shown not to be always true in the
 sense that the initial quantum state of measured system can be retrieved with a nonzero probability.
 This is because the quantum state is not fully perturbed when the interaction between the
 measured and probing systems is weak. We introduce how we quantify the reversibility of quantum
 measurement and its potential applications to various protocols for transferring quantum information.