Revista Brasileira de Ensino de Física
Print version ISSN 1806-1117
PIQUEIRA, José Roberto Castilho. Quantum information theory: non-cloning, entanglement and teleportation. Rev. Bras. Ensino Fís. [online]. 2011, vol.33, n.4, pp.4303-4303. ISSN 1806-1117. http://dx.doi.org/10.1590/S1806-11172011000400003.
The idea of developing computers with dynamics obeying Quantum Mechanics laws comes from the last quarter of 20th century assuming, nowadays, a remarkable technological and scientific importance, as the use of quantum algorithms has been disseminated on implementing cryptography systems and, besides, quantum channel experiments start to become present in the literature. There are, even, conjectures about quantum behaviors in synapses and in other natural phenomena considered to be macroscopic. All these developments are based on Quantum Information Theory that, generally speaking, could be considered an extension of Classical Information Theory, due to Shannon, taking into account two peculiar aspects of quantum phenomena: the impossibility of copying a quantum state and the mutual dependence shown by two states originated in their preparation. This work is about these two points without originality intentions, presents the concept of entanglement and the proof of the non-conning theorem. Some applications, mixed with fiction, are presented and possible similarity with real facts is a mere coincidence.
Keywords : Bell inequalities; Hilbert spaces; tensor product; qubit.