How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Homology object of a chain complex
Definition
Let be a chain complex and let be the canonical morphism supplied by The boundary subobject factors through the cycle subobject.
The th homology object of is the cokernel
Equivalently, one writes with the understanding that this quotient notation abbreviates the cokernel of the canonical monomorphism from boundaries to cycles.
Depends on
Used by
- Gaussian cancellation preserves homotopy type and abelian-category homology Corollary
- One Element Koszul Homology Corollary
- A universal-coefficient splitting cannot in general be chosen naturally Counterexample
- Sum and product totalisations on an infinite diagonal Counterexample
- The isolated differential 2 on the integers cannot be cancelled Counterexample
- Augmentation and reduced simplicial homology Definition
- Derived schemes and the cotangent complex of a morphism Definition
- Exact couple Definition
- Hochschild chains and Hochschild homology with coefficients Definition
- Homological spectral sequence Definition
- Koszul Regular And H One Regular Sequences Definition
- Left derived objects relative to supplied projective resolution data Definition
- Morse homology of a Morse--Smale pair Definition
- Simplicial cycles, boundaries, and homology Definition
- Simplicial objects, simplicial commutative rings and homotopy groups Definition
- The connecting morphism in homology Definition
- The evaluation map from cohomology to Hom of homology Definition
- The homology cross product for tensor complexes Definition
- The preconnecting arrow on cycles Definition
- The relative homology of a chain map Definition
- The singular chain complex and singular homology Definition
- A two-term complex has kernel and cokernel homology Example
- A unit pivot forces the minus Schur sign Example
- A zero-differential complex has homology equal to each term Example
- Universal-coefficient homology with cyclic coefficients Example
- H0 of the cotangent complex and the polynomial case Lemma
- Independence of the cotangent complex from the chosen simplicial resolution Lemma
- The cycle-boundary short exact sequences for a free complex over a PID Lemma
- The homological universal-coefficient edge map is well defined Lemma
- The low-degree filtration sequence of a first-quadrant bicomplex Lemma
- The preconnecting arrow annihilates boundaries Lemma
- The strict simplicial algebra adjunctions underlying the cotangent construction Lemma
- Degree-zero Hochschild homology is bimodule coinvariants Proposition
- Homology of a shift is shifted homology Proposition
- The handle chain complex computes singular homology Proposition
- A chain map induces a well-defined map on homology Theorem
- A chain map is a quasi-isomorphism exactly when its cone is acyclic Theorem
- A complex is exact at n exactly when its nth homology is zero Theorem
- An exact functor commutes with homology Theorem
- Chain-homotopic maps induce the same map on homology Theorem
…and 5 more results.
Dependency tree · two levels
8 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- Charles A. Weibel, Chapter 1 of An Introduction to Homological Algebra (standard reference, not scraped)
- The Stacks Project, Section 12.13: Complexes (standard reference, not scraped)