Jim is a theoretical nuclear physicist based at the University of Surrey where he holds a personal chair in physics as well as university chair in the Public Engagement in Science. He also holds an EPSRC Senior Media Fellowship.

In addition to being an academic, he is author of a number of popular science books and a broadcaster. Until recently he was the Recorder for the Physics and Astronomy Section of the BA and has been an active member of the BA Council since 2003.  In 2004 he was chosen as one of twenty-one "Faces of UK Science" on permanent exhibition in London's National Portrait Gallery.