Decoherence for Markov chains

Abstract

The subspace generated by the eigenvectors pertaining to the peripheral spectrum of any stochastic matrix is naturally equipped with a structure of a (finite dimensional abelian) $C^*$-algebra, and the restriction of such a stochastic matrix to this subspace, indeed a $C^*$-algebra under this canonical new product, generates a conservative $C^*$-dynamical system.