In this work a survey of recent results about the conditions on even type, indefinite, unimodular, 

symmetric bilinear forms over the integers as intersection forms of simply connected, closed, oriented, 

smooth 4-manifolds is given. In this context a proof of a recent result of M. Furuta which is so far the 

closest result in the direction of so called 11/8-conjecture is presented in detail.

Keywords: Intersection Forms, Seiberg-Witten Equations, 4-Manifolds.