Cochain Complex
- Natural & Formal Sciences -
Mathematics & Logic Dictionary
Definition
A graded sequence of cochain groups or modules C^n with coboundary maps δ^n: C^n → C^{n+1} satisfying δ^{n+1} ∘ δ^n = 0; its cohomology H^n = ker δ^n / im δ^{n-1} measures obstructions dual to chain homology.