NUI MAYNOOTH  DEPARTMENT OF MATHEMATICAL PHYSICS SEMINAR

Friday 10th February 2006 at 3.30pm

Lecture Hall CS1, Callan Building, NUIM North Campus


Prof. Tony Dorlas
School of Theoretical Physics, Dublin Institute for Advanced Studies

Efficient transmission of quantum information.

For the transmission (or storing) of classical information a variety of error-correcting codes is in use. By introducing some redundancy in the information it is protected to some extent from random errors. It is known that there is an upper limit to the rate with which such coded information can be transmitted. This is called the capacity of the information channel and Shannon has found an explicit expression for it.

Quantum information comes in the form of n-qubits, i.e. states of a system of n two-level systems, spin-1/2 particles for example. We shall show that there exists an analogue of error-correcting codes for such states. Moreover, we discuss the proof of a quantum analogue of Shannon's theorem.