Denis Evans


NONLINEAR RESPONSE THEORY AND THE FLUCTUATION THEOREM



Nonlinear Response Theory and the Fluctuation Theorem

Denis J. Evans
Research School of Chemistry
Australian National University
Canberra, ACT 0200 Australia
Fax: +61-2-61259611

email: evans@rsc.anu.edu.au

Debra J. Searles
School of Science
Griffith University
Brisbane, Qld 4111 Australia
Fax: +61-7-38753921

email: D.Bernhardt@mailbox.gu.edu.au

Lamberto Rondoni
Dipartimento di Mathematica and INFM, Politecnico di Turino,
Torino Italy

email: rondoni@polito.it


Recently there has been considerable theoretical and experimental interest in the so-called Fluctuation Theorem. This Theorem shows how time reversible microscopic dynamics leads to irreversible macroscopic behavior as either the system size or the observation time increases.

In the present paper we show that the argument of the Evans-Searles Fluctuation Theorem, the dissipation function, also plays a central role in nonlinear response theory. Exact expressions for the nonlinear response of a classical N-body system to a nonequilibrium process, are derived in terms of the Evans-Searles dissipation function.

These expressions should be verifiable in the laboratory. When linearized these expressions reduce to the well known Green-Kubo expressions for the linear response.