The Role of Covariancy in Calculating Capacity of Quantum Channels Generated by Projective Unitary Representations of Non-Abelian Groups
摘要
Abstract
We study quantum channels generated by irreducible projective unitary representations of finite groups. It is shown that to calculate a classical capacity of channel it is not necessary to claim that it is covariant with respect to a representation. It helps to consider non-Abelian groups because in this case such channels are not covariant respect to the generating representation.