Evaluating Communication in the British Parliamentary Public Sphere

This article begins with a re-evaluation of political communication research based on Habermas' original theory of the public sphere. It presents Habermas' alternative framework for assessing communication in contemporary ‘actually existing democracies’. The model is then tested with a case study of the UK parliamentary public sphere based on 95 semi-structured interviews with political actors (politicians, journalists and officials). It concludes that parliament today operates rather better, according to public sphere norms, than the public sphere described in Habermas' accounts of 18th and 19th-century England. Such a finding, on its own, is clearly at odds with public perception. The research accordingly offers two explanations for this disparity and the (perceived) crisis of political legitimacy in UK politics

Lattice Boltzmann simulations of soft matter systems

This article concerns numerical simulations of the dynamics of particles immersed in a continuum solvent. As prototypical systems, we consider colloidal dispersions of spherical particles and solutions of uncharged polymers. After a brief explanation of the concept of hydrodynamic interactions, we give a general overview over the various simulation methods that have been developed to cope with the resulting computational problems. We then focus on the approach we have developed, which couples a system of particles to a lattice Boltzmann model representing the solvent degrees of freedom. The standard D3Q19 lattice Boltzmann model is derived and explained in depth, followed by a detailed discussion of complementary methods for the coupling of solvent and solute. Colloidal dispersions are best described in terms of extended particles with appropriate boundary conditions at the surfaces, while particles with internal degrees of freedom are easier to simulate as an arrangement of mass points with frictional coupling to the solvent. In both cases, particular care has been taken to simulate thermal fluctuations in a consistent way. The usefulness of this methodology is illustrated by studies from our own research, where the dynamics of colloidal and polymeric systems has been investigated in both equilibrium and nonequilibrium situations.Comment: Review article, submitted to Advances in Polymer Science. 16 figures, 76 page