Per Enflo is famous for solving Banach's basis problem, Grothendieck's approximation problem, and the invariant subspace problem for general Banach spaces, and has other fundamental research in linear and non linear geometric functional analysis. He also has done research in population dynamics. A child prodigy as a pianist, he continues to give concerts in Europe and the United States, but you can hear him at home by creating a Per Enflo station on Spotify.