Mark’s mathematical career has been spent in America, Britain and Germany, and he is now honorary professor of mathematics at University College London (UCL) and emeritus professor at the University of Illinois at Chicago (UIC). In addition to extensive research, and teaching at all levels, his book Symmetry and the Monster, describing the quest to find all the basic building blocks for symmetry, brings advanced mathematics to a general audience.

As well as  mathematics he has also taught university courses on the ancient literature of Mesopotamia — including the Epic of Gilgamesh — and the history of the calendar.

Mark also writes essays and book reviews, particularly for Standpoint magazine and History Today, contributes occasional opera reviews to the Daily Telegraph and New Statesman, and has served on the Olivier Awards Committee for Opera.