He is principally known for his work in non-equilibrium thermodynamics and mathematical modelling of cellular phenomena, in particular human production of insulin.
Keizer used the canonical form for the first formulation of statistical thermodynamics valid in far from equilibrium regimes, where the Onsager reciprocal relations and the Albert Einstein formula for the fluctuations do not work.
Cosma Shalizi wrote: Chapter five applies the canonical theory to various chemical and electrochemical processes.
Keizer was, until his premature death in May, 1999, an active and talented scientist who played a significant role not merely in the development of the formal structure of far from equilibrium thermodynamics, but also in its application to experiment, especially in biology.
Unlike a number of others who have attempted such cross-overs, he made it work.Besides the unification of disparate topics as chemical reactions, hydrodynamics, or heat transport in solids, the canonical theory has been applied to solving the problems of traditional disciplines as statistical mechanics.