Blown-up Čech cohomology and Cartan’s Theorem B on real algebraic varieties
Abstract
We introduce a concept of blown-up Čech cohomology for coherent sheaves of homological dimension ≤1 and some quasi-coherent sheaves on a nonsingular real affine variety. Its construction involves a directed set of multi-blowups. We establish, in particular, long exact cohomology sequence and Cartan’s Theorem B. Finally, some applications are provided, including universal solution to the first Cousin problem (after blowing up).