分野別セミナー

A point x of a real manifold X smoothly embedded in a complex space is said to be complex tangent if the tangent space of X at x contains a non-trivial complex linear subspace. For an embedded 3-sphere in the 3-dimensional complex space, the set of complex tangent points generically forms a 1-dimensional submanifold of the 3-sphere (or is empty). We talk about an ongoing study (joint with Naohiko Kasuya, Aoyama Gakuin University) on such a set of complex tangent points with relation to classical knot theory.