title: Equivalence of stationary state ensembles.
abstract: We show that the contact process in an ensemble with conserved total particle number, as simulated recently by Tomé and de Oliveira [Phys. Rev. Lett. 86, 5463 (2001)], is equivalent to the ordinary contact process, in agreement with what the authors assumed and believed. Similar conserved ensembles and equivalence proofs are easily constructed for other models.
authors.affiliation: Laboratoire de Physique Théorique, Laboratoire associé au CNRS-UMR 8627, Bâtiment 210, Université de Paris-Sud, 91405 Orsay Cedex, France.
authors.forename: H J
authors.initials: HJ
authors.lastname: Hilhorst
authors.forename: F
authors.initials: F
authors.lastname: va Wijland