Fluctuation-induced chiral symmetry breaking in autocatalytic reaction-diffusion systems

We show how spatiotemporal fluctuations can induce spontaneous symmetry breaking in systems which are perfectly symmetric in the absence of fluctuations. We illustrate this in the context of the autocatalytic production of chiral enantiomers from achiral reactants in reaction-diffusion systems. The mean-field steady state is chiral symmetric; spatiotemporal fluctuations induce global and complete chiral ordering with sharp phase transitions including re-entrance. We find that advective mass transport enhances the tendency to break chiral symmetry. We discuss the relation between our study and recent experiments demonstrating complete chiral symmetry breaking (CSB), and its implications to the emergence of molecular homochirality. Copyright (C) EPLA, 2007.