BibliographyType,ISBN,Identifier,Author,Title,Journal,Volume,Number,Month,Pages,Year,Address,Note,URL,Booktitle,Chapter,Edition,Series,Editor,Publisher,ReportType,Howpublished,Institution,Organizations,School,Annote,Custom1,Custom2,Custom3,Custom4,Custom5
5,"","statphys23_0318","Baumann, F.; Gambassi, A.; Henkel, M.; Pleimling, M. & Richert, J.","Ageing in reaction-diffusion systems","",,,"9-13 July","",2007,"Genova, Italy","","http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=318","Abstract Book of the XXIII IUPAP International Conference on Statistical Physics","","","","Pietronero, Luciano; Loreto, Vittorio & Zapperi, Stefano","","","","","","","","The investigation of ageing phenomena in critical reaction-diffusion systems, like for instance the (fermionic) contact process (directed percolation), has started only recently [1,2]. To some surprise it was found that the ageing exponents $a$ and $b$, that describe the scaling behaviour of the autoresponse and of the autocorrelation, are not equal, in contrast to critical systems with detailed balance where the identity $a=b$ holds. As a consequences the definition of the fluctuation-dissipation ratio must differ in these systems from that used in critical magnetic systems. 
In this contribution we first look at the contact process from a field-theoretical point of view [3], confirming the above result that a and b do not agree. We then suggest an interpretation of the modified definition of the flucutation-dissipation ratio (which was already proposed in [2]) for this specific system. We also look at a different type of reaction-diffusion system which allows for an exact solution [4]. Also in this case, the above inequality of a and b is confirmed, but the relation between them is not identical to the relation found for the critical contact process. \\
1) T. Enss, M. Henkel, A. Picone, U. Schollwoeck, J. Phys. A: Math. Gen. {\bf 37}, 10479.\\ 2) J.J. Ramasco, M. Henkel, M.A. Santos, and C.A. da Silva Santos, J. Phys A: Math. Gen. {\bf 37}, 10497.\\ 3) F. Baumann and A. Gambassi, J. Stat. Mech. P01002 (2007).\\ 4) F. Baumann, M. Henkel, M. Pleimling, and J. Richert, J.Phys. A: Math. Gen. {\bf 38}, 6623 (2005).","","ageing directed fluctuation-dissipation percolation ratio reaction-diffusion statphys23 systems topic-4 ","",""