A few splitting theorems for rank two vector bundles on P^4

The paper investigates vanishing conditions on the intermediate cohomology of a normalized rank 2 vector bundle on which force to split or, at least, to be a non-stable bundle (with few possible exceptions). The results are applied to see when subcanonical surfaces in are forced to be complete intersections of two hypersurfaces, since subcanonical surfaces are zero loci of non-zero sections of rank vector bundles.