3:30 p.m., Friday
Professor Stuart G. Whittington
Department of Chemistry
University of Toronto
Coloured self-avoiding walks
Self-avoiding walks have been studied, partially because they can be regarded as models of linear polymer molecules. If the vertices of the walks are coloured (A or B, say), they can be regarded as models of copolymers in which the two types of monomers (A and B) behave
differently. The colouring can be periodic (eg ABABAB...) or random (eg
vertices are coloured independently, A with probability p and B with
probability 1-p). Phase transitions in such systems are signalled by
singularities in the free energy and the location of the singularity can
depend on the colouring. In the random case interest centres on
self-averaging phenomena, in which one is interested in questions like
``Do almost all colourings give rise to almost the same value of some
property of the walks?". Recent results on both types of colouring
will be presented.
Refreshments will be served in Math Annex Room 1115, 3:15 p.m.