Grafting Seiberg-Witten monopoles

We demonstrate that the operation of taking disjoint unions of J-holomorphic curves (and thus obtaining new J-holomorphic curves) has a Seiberg-Witten counterpart. The main theorem asserts that, given two solutions (A(i), psi(i)), i = 0, 1 of the Seiberg-Witten equations for the Spin(c)-structures W-Ei(+) E-i circle plus (E-i circle times K-1) (with certain restrictions), there is a solution (A, psi) of the Seiberg-Witten equations for the Spin(c)-structure W-E with E = E-0 circle times E-1, obtained by "grafting" the two solutions (A(i), psi(i)).