Florian Baumann et al 2006 J. Phys. A: Math. Gen. 39 4095 doi:10.1088/0305-4470/39/16/001
Florian Baumann1,2, Stoimen Stoimenov2,3 and Malte Henkel2,4
Show affiliationsLocal scale invariance for ageing systems without detailed balance is tested through studying the dynamical symmetries of the critical bosonic contact process and the critical bosonic pair-contact process. Their field-theoretical actions can be split into a Schrödinger-invariant term and a pure noise term. It is shown that the two-time response and correlation functions are reducible to certain multipoint response functions which depend only on the Schrödinger-invariant part of the action. For the bosonic contact process, the representation of the Schrödinger group can be derived from the free diffusion equation, whereas for the bosonic pair-contact process, a new representation of the Schrödinger group related to a nonlinear Schrödinger equation with dimensionful couplings is constructed. The resulting predictions of local scale invariance for the two-time responses and correlators are completely consistent with the exactly-known results in both models.
05.70.Jk Critical point phenomena
05.10.Gg Stochastic analysis methods (Fokker-Planck, Langevin, etc.)
82C27 Dynamic critical phenomena
82C22 Interacting particle systems (See also 60K35)
81R50 Quantum groups and related algebraic methods (See also 16W35, 17B37)
Issue 16 (21 April 2006)
Received 25 October 2005, in final form 7 February 2006
Published 31 March 2006
Florian Baumann et al 2006 J. Phys. A: Math. Gen. 39 4095