Professor Andrew Archer

Andy Archer is a Professor of Applied Mathematics and Theoretical Physics at Loughborough University. His research uses methods from statistical mechanics, pattern formation and dynamical systems theory to understand the behaviour of soft condensed matter, in both the liquid and solid phases. He obtained both his undergraduate (MSci, Physics) and his PhD (in Theoretical Physics) from the University of Bristol in 2003 and then spent a further 3 years in Bristol as an EPSRC Postdoctoral Research Fellow in Theoretical Physics. After a brief postdoc at the University of Bath, at the end of 2006 he became a Lecturer and RCUK Fellow at Loughborough University. He was subsequently promoted to Senior Lecturer in 2013
and Professor in 2017.

Topics of current interests are:

(i) Working to develop theories to understand the phase behaviour of fluids: address how and why soft matter systems freeze or form a glass or why even occasionally such systems can order to form quasicrystals.
Also study the dynamics of these phase changes.

(ii) Developing the mathematics for predicting rare events, such as in chemical transitions
and structural or phase changes in materials.

(iii) The behaviour of liquids at interfaces, such as the wetting properties of a liquid.

(iv) To understand and predict the structures and patterns that are formed when a thin film of colloidal suspension is placed on a surface and the solvent subsequently evaporates. As the liquid evaporatively dewets, regular line patterns, branched finger patterns, network patterns and other structures can be formed by the colloids that are deposited on the surface.

(v) Develop "dynamical density functional theories", which are theories to describe the microscopic structure
and dynamics of colloidal fluids.

Talk abstract: Theory of inhomogeneous liquids in and out of equilibrium: density functional theory
and its dynamical extensions

This summer school is all about soft matter, liquids and complex fluids. These particular lectures and tutorial will be on theories for describing such systems when they are nonuniform, such as at interfaces or in the presence of other external fields, both at equilibrium and out of equilibrium. In equilibrium, the theory is classical density functional theory (DFT, not to be confused with its more well-known quantum-DFT cousin, which is a theory for electrons). Classical DFT is a theory for the structure and thermodynamics of inhomogeneous classical liquids. It can be used, for example, to determine the density distribution of a liquid in the vicinity of a container wall and to determine the corresponding interfacial tension. We will then go on to cover the dynamical extension of DFT (DDFT), which in its simplest form is a theory for the dynamics of colloids or other such Brownian particles in solution, but can also be extended to include the effects of inertia which are required for fluid dynamics more generally. DDFT is used, for example, to describe dynamics during drying of complex liquids on surfaces and the patterns they can leave behind.