1. Walter Kohn received his BA at UofT in Math and Physics in 1945 and his MA from UofT in Applied Mathematics. Kohn was a co-winner of the Nobel Prize in Chemistry in 1998.  He was cited for his development of the now-famous density functional theory for calculating the electronic structure of atoms, molecules and solids.  This method sidesteps the difficult problem of calculating many particle wavefunctions. Kohn might have won the Nobel Prize in Physics for this work. He also has done fundamental studies on interacting Fermi systems (Fermi liquid theory), properties of metal surfaces, and the electronic states of impurities in semiconductors. Kohn was the founding director of the Institute of Theoretical Physics at Santa Barbara in 1979, now a leading world centre for workshops in theoretical physics.
2. Bertram Brockhouse did his BA at UBC, and his MA (1948) and PhD (1950) at Toronto. Brockhouse was a co-winner of the Nobel Prize in Physics in 1994 for his development of neutron spectroscopy.  Working at Chalk River Nuclear Laboratories (AECL) in the 1950's, Brockhouse did the first experiments probing condensed matter using inelastic scattering of neutrons.  He used this powerful method to study phonons in crystals and spin waves in ferromagnets. 
3. Arthur Schawlow (1921-1999) did both his undergraduate and graduate studies (PhD 1949) at UofT. Schawlow was a co-winner of the Nobel Prize in Physics in 1981 for his outstanding contribution to the development of laser spectroscopy. His work with Townes led to the development of  the laser.  Later with Hansch, Schawlow developed the idea behind laser cooling of atoms.  This method is the key to reaching the very low temperatures needed to Bose-condense trapped atoms (BEC).
   

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