  We investigate the capability of Symplectic quandles to detect causality for
(2+1)-dimensional globally hyperbolic spacetimes (X). Allen and Swenberg showed
that Alexander-Conway polynomial is insufficient to distinguish connected sum
of two Hopf links from the links in the family of Allen-Swenberg 2-sky like
links, suggesting that it can not always detect causality in X. We find that
symplectic quandles, combined with Alexander-Conway polynomial, can distinguish
these two type of links, thereby suggesting their ability to detect causality
in X. The fact that symplectic quandles can capture causality in the
Allen-Swenberg example is intriguing since the theorem of Chernov and
Nemirovski, which states that Legendrian linking equals causality, is proved
using Contact Geometry methods.
