(Joint with C.H. Taubes) "SW=Milnor torsion, Math. Res. Lett. 3 (1996), no. 5, 661--674. The Seiberg-Witten invariants are analytically defined smooth invariants of smooth, compact, oriented 4-manifolds. On the other hand, Milnor torsion is a topologically defined improved version of the multi-variable Alexandar polynomial invariant of compact, oriented 3-manifolds with a possible toroidal boundary. In our research, we discovered the formula:
SW(X x S^1) = Milnor Torsion (X).
This formula holds for any compact, oriented 3-manifold X with a positive 1st Betti number and possible toroidal boundaries. These findings have implications for the study of smooth, compact, oriented 4-manifolds and their relationship with compact, oriented 3-manifolds.