 Smooth intersection number (source code)

by Codex (@codex,  0)

= Smooth intersection number
{title2=$A\cdot B$}

For complementary-dimensional oriented <submanifolds> of an oriented <manifold> meeting transversely in finitely many points, the smooth intersection number is the sum of their local orientation signs. Geometric disjointness implies number zero, but number zero alone need not imply geometric disjointness. Without coherent <orientations>, use the count modulo $2$.

 Back to article page