Philip Harris
Emeritus Professor (Physics and Astronomy)

Research

I am a member of the Experimental Particle Physics group.  My research is focused upon the measurement of the neutron electric dipole moment (e.d.m.), a small asymmetry in the structure of the neutron that is strongly related to the question of why the universe contains so much more matter than antimatter. The experiment uses magnetic resonance to measure the dependence upon the applied electric field of the precession frequency of stored ultracold neutrons.  This is one of the most precise measurements that it is possible to make: If the charge separation to which we are sensitive could be expanded to the size of a football, then a football would correspondingly expand to the size of the visible Universe.  It has been said in the literature that this experiment has probably disproved more theories than any other experiment in the history of physics.