Simple physics in a complex world

Abstract

I nearly entitled my lecture 'Many body problems' and probably would have done so, but for the fact that, in modern theoretical physics, the term 'many body problems' has become much too highbrow for the kinds of problems, both in and out of physics, that seem to have come my way. The many body world is complex and this is because the many bodies which make it up — whether atoms in a piece of iron, rods of uranium and blocks of graphite in a nuclear reactor, plants and animals in a woodland, people in society, departments in a government, nations in the world — these bodies all act upon one another in a tremendous tangle of interconnections.