Response to “Comment on ‘Markovian approximation in a coarse-grained description of atomic systems’ ” [J. Chem. Phys. 128, 147101 (2008)

Abstract

We show within the Mori theory of projection operators that the Green-Kubo formula using microscopic rather than projected forces is only valid if the description is Markovian. Therefore, the only way to assess whether a description is Markovian is through examining the predictions of the theory under the Markovian assumption. Although, in principle, the blob description for a unidimensional chain is non-Markovian, in practice the Markovian approximation describes reasonably well the coarse dynamics of the chain.