| Citation | Distinguished for his work on the mathematical basis of statistical mechanics. Penrose has worked on many problems in statistical physics. A notable early success being his estimate (with L. Onsager) of the proportion of condensate in liquid helium, but his later interests have moved to the rigorous derivation of statistical mechanics and ergodic behaviour where he enjoys an international reputation. Particularly noticeable has been his vigorous resolution of the conditions under which Van der Waals equation holds. |