2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/147194In this paper we describe the Seiberg-Witten invariants, which have been introduced by Witten, for manifolds with $b_+=1$. In this case the invariants depend on a chamber structure, and there exists a universal wall crossing formula. For every Kähler surface with $p_g=0$ and $q$=0, these invariants are non-trivial for all $Spin^c(4)$-structures of non-negative index.LaTeX, 27 pages. To appear in Int. J. MathAlgebraic GeometryDifferential GeometryHigh Energy Physics - Theorytext