doctoral_advisor influenced birth_place influences awards fields workplaces doctoral_students birth_date known_for residence image article_title name alma_mater
hans rådström bernard beauzamy stockholm , sweden joram lindenstrauss laurent schwartz mazur for solving `` scottish book '' problem 153 's '' -lsb- http://www.apprendre-math.info/history/photos/mazur_2.jpeg live goose -rsb- '' functional analysis operator theory analytic number theory university , paris the royal institute of technology , stockholm kent of state university california , berkeley stanford university École polytechnique nilson reznick anthony weston bernardes miguel lacruz jan-ove larsson marie lövblom bruce 20 may 1944 approximation infinite-dimensional -rrb- uniformly convex renorms of super-reflexive banach spaces embedding problem metric spaces -lrb- unbounded distortion of cube -rrb- `` concentration schauder '' of polynomials at low degree invariant subspace problem basis hilbert 's fifth problem -lrb- kent , ohio , united states per enflo.jpg per enflo
 per enflo stockholm university
per enflo

per h. enflo -lrb- ; born 1944 -rrb- is a mathematician who has solved fundamental problems in functional analysis .
three of these problems had been open for more than forty years : the basis problem and the approximation problem and later the invariant subspace problem for banach spaces .
in solving these problems , enflo developed new techniques which were then used by other researchers in functional analysis and operator theory for years .
some of enflo 's research has been important also in other mathematical fields , such as number theory , and in computer science , especially computer algebra and approximation algorithms .
enflo works at kent state university , where he holds the title of university professor .
enflo has earlier held positions at the university of california , berkeley , stanford university , École polytechnique , -lrb- paris -rrb- and the royal institute of technology , stockholm .
enflo is also a concert pianist .
