Citation | Professor Fisher is distinguished for his contributions to mathematical physics, particularly statistical mechanics. In early papers he developed the matrix theory of transmission lines, and introduced new methods for the analogue solution of integral and differential equations. His first major achievements in lattice statistics included a rigorous theory of the superexchange anitferromagnet, and of an assembly of dimers, in two dimensions. He has made important contributions to the theory of self-avoiding random walks, to percolation theory and to the theory of the critical point in fluid systems. More recently he has demonstrated the essential singularity of the condensation point on a fluid isotherm, and has obtained general sufficient conditions for the free energy of a macroscopic system to be an intensive quantity. His work is characterized by physical insight and mathematical rigour. At an early age he has become an international authority on equilibrium statistical mechanics. |