Affine linking numbers and causality in spacetimes

Linking numbers are classically defined only for zero homologous linked submanifolds. Jointly with Rudyak we constructed affine linking number generalizing this to arbitrary linked submanifolds. We apply these affine linking numbers to the study of causality in spacetimes and discuss when they are enough to completely capture causality.

Zoom (new link!): https://zoom.us/j/97302991744
Access code: the Euler characteristic of the wedge of two circles
(the password is not the specified phrase but the number that it determines)