Abstract Kernels and Cohomology

Correctness kernels of abstract interpretations

In static analysis, approximation is typically encoded by abstract domains, providing systematic guidelines for specifying approximate semantic functions and precision assessments. However, it may happen that an abstract domain contains redundant information for the specific purpose of approximating a given semantic function modeling some behavior of a system. This paper introduces correctness ...

Abstract Homotopy Theory and Generalized Sheaf Cohomology

HOMOTOPY THEORY AND GENERALIZED SHEAF COHOMOLOGY BY KENNETHS. BROWN0) ABSTRACT. Cohomology groups Ha(X, E) are defined, where X is a topological space and £ is a sheaf on X with values in Kan's category of spectra. These groups generalize the ordinary cohomology groups of X with coefficients in an abelian sheaf, as well as the generalized cohomology of X in the usual sense. The groups are defin...

Kernels and Cohomology Groups for Some Finite Covers

We extend work of G. Ahlbrandt and M. Ziegler to give a classiication of the nite covers with bre group of prime order p for the projective space over the eld with p elements, and for the Grassmannian of k-sets from a disintegrated set (for k 2 N). AMS classiication: 03C35 and 20B27. This paper is a contribution to the study of the ne detail of the class of (countable) totally categorical struc...

Topological Methods in Abstract Algebra. Cohomology Theory of Groups

An Efficient Identification Scheme Based on Permuted Kernels (Extended Abstract)