EntityQ1017338· pop 6· linked from 34 articlesobstruction theorySign in to saveMathematical theoriesConnectionshomotopyEntitycohomologyEntityN-skeletonEntitymathematicsEntityInternational Standard Book NumberEntitytheoryEntitycontinuous functionEntitymanifoldEntityvector fieldEntityinvariantEntityconnected spaceEntitySamuel EilenbergEntitysimply connected spaceEntityHassler WhitneyEntitydiffeomorphismEntityn-sphereEntityvector bundleEntitysimplicial complexEntityfiber bundleEntitytopological manifoldEntityCategoriesDifferential topologyHomotopy theorySurgery theoryTheories