Paolo Dai Pra, Anna Maria Paganoni and Gustavo Posta Entropy inequlities for unbounded spin systems (261K, Postscript) ABSTRACT. We consider nonconservative, reversible spin systems, with unbounded discrete spins. We show that for a class of these dynamics in a high temperature regime, the relative entropy with respect to the equilibrium distribution decays exponentially in time, although the logarithmic-Sobolev inequality fails. To this end we prove a weaker modification of the logarithmic-Sobolev inequality.