Nockstein

The Bockstein homomorphism is a concept in algebraic topology, a branch of mathematics that studies shapes and spaces. It helps connect different types of cohomology groups—tools that measure the structure of spaces—especially when working with coefficients (values) like integers modulo a number. Think of it as a method to detect hidden features in a space by analyzing how these features change when moving from one level of detail to another, particularly through exact sequences. Essentially, the Bockstein homomorphism links complex algebraic information, revealing deeper properties of the underlying space.