EntityQ1972470· pop 19· linked from 571 articlesunitary operatorSign in to savesurjective bounded operator on a Hilbert space preserving the inner productConnectionsinner product spaceEntitybounded operatorEntityInternational Standard Book NumberEntitycomplex numberEntityintegerEntitytopologyEntitygroupEntityvector spaceEntityabsolute valueEntityrotationEntityscalar productEntityFourier transformEntityHilbert spaceEntityisomorphismEntityunit circleEntityfunctional analysisEntityRiemann hypothesisEntitysurjective functionEntitycategory theoryEntitycalculus of variationsEntityCategoriesLinear operatorsOperator theoryUnitary operators