DIFFERENTIABLE ACTIONS OF HOMOTOPY SEVEN SPHERES, II.
PENNSYLVANIA UNIV PHILADELPHIA
Pagination or Media Count:
The paper presents a theorem which shows that there are exactly six unoriented homotopy 7-spheres not diffeomorphic to one another such that on each of them there is a free differentiable action of the circle group. Moreover, on any homotopy 7-sphere, if there exists a free differentiable action of the circle group, then there are infinitely many topologically distinct from one another.
- Theoretical Mathematics