Quantum Computation and Information Seminar 

16/01/2004, 15:00 — 16:00 — Room P4.35, Mathematics Building
Yasser Omar, Instituto Superior Técnico

Entanglement, or the Physics of Teleportation

The entanglement of quantum states was first pointed out by E. Schrödinger in 1935 as "the characteristic trait of quantum mechanics", but only in the last decade did it start becoming better understood and seen as a resource for many applications. Entanglement offers correlations with no classical equivalent that can be used for quite novel and unique information processing tasks, such as quantum teleportation, quantum dense coding of information and unconditionally secure quantum cryptographic key distribution, amongst others. Entanglement may also be a sufficient condition for the speed-up of certain quantum algorithms over their classical counterpart and is an important tool for quantum error correction. Yet, associated to the issue of non-locality since the EPR problem (Einstein, Podolsky and Rosen, 1935), and despite the progress allowed by Bell's theorem in 1964 and subsequent results, entanglement remains one of the most surprising and mysterious aspects of quantum mechanics. This talk will attempt to introduce the essential ideas concerning entanglement and explain how it can be used for the teleportation of a quantum state.