Vitaly N. Efimov (Russian: Вита́лий Ефи́мов) is a Russian theoretical physicist. He proposed the existence of a novel and exotic state of matter now dubbed the Efimov State as a researcher in A.F. Ioffe Physico-Technical Institute, USSR Academy of Sciences, Leningrad, USSR in his 1970 paper "Energy levels arising from resonant two-body forces in a three-body system" (Physics Letters B, 33:563-4). It was announced in 2006 that the existence of this state of matter had been confirmed.[1]
He is now an affiliate professor of physics at the University of Washington.