3 papers
math.GT2018
Generic immersions and totally real embeddings
Naohiko Kasuya, Masamichi Takase
We show that, for a closed orientable n-manifold, with n not congruent to 3 modulo 4, the existence of a CR-regular embedding into complex (n-1)-space ensures the existence of a to…
math.GT2005
The Hopf invariant of a Haefliger knot
Masamichi Takase
We show that Haefliger's differentiable (6,3)-knot bounds, in 6-space, a 4-manifold (a Seifert surface) of arbitrarily prescribed signature. This implies, according to our previous…
math.GT2005
Homology 3-spheres in codimension three
Masamichi Takase
For smooth embeddings of an integral homology 3-sphere in the 6-sphere, we define an integer invariant in terms of their Seifert surfaces. Our invariant gives a bijection between t…