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.
Long exact sequence of a pair
Statement
For there is an exact sequence
Facts & Assumptions
Given: A subspace .
Proof
Inclusion and quotient form a degreewise short exact sequence .
The long-exact-sequence theorem for a short exact sequence of complexes applied to step 1.1 gives precisely the displayed sequence, with the third homology group equal to relative homology by definition.
Depends on
Used by
- Euler number ±1 makes the Milnor sphere bundle a homotopy seven-sphere Corollary
- Good pairs and quotient reduced homology Corollary
- Homotopy spheres of dimension at least five bounding a contractible manifold are standard spheres Corollary
- A homology cobordism need not be an h-cobordism Counterexample
- A homology equivalence need not be a homotopy equivalence without simple connectivity Counterexample
- Excision fails without closure inside interior Counterexample
- Absolute and relative Hurewicz homomorphisms Definition
- Cellular boundary from three consecutive skeleta Definition
- Local degree at an isolated preimage Definition
- Relative connecting homomorphism on cycles Definition
- The unreduced Burau relative homology module Definition
- A simply connected CW homology equivalence is a homotopy equivalence under the stated choice conditions Example
- Integral cohomology ring of a closed orientable surface Example
- Local degrees of a polynomial map on the riemann sphere Example
- Poincaré–Lefschetz duality for a disk Example
- Relative homology of a disk and its boundary Example
- Relative homology of an interval and its endpoints Example
- A collar constructs the relative orientation class and its boundary class Lemma
- A CW quotient induces relative singular homology isomorphisms Lemma
- A multiple of a fork surface has a closed compact replacement Lemma
- A product collar deformation retracts onto its face Lemma
- A rational homology four-ball has square boundary torsion order Lemma
- A relative single cell layer has compatible homotopy and homology bases Lemma
- Attaching handles of index at least q preserves homology below q-1 Lemma
- Cap duality on a Euclidean coordinate ball Lemma
- Cellular boundary coefficients are the signed trajectory counts Lemma
- Cellular reduction for a highly connected pair Lemma
- Compatible orientation classes over compact subsets Lemma
- Connected sum descends to oriented h-cobordism classes Lemma
- Connected sum preserves oriented homotopy spheres Lemma
- Coordinate-ball classes identify local homology stalks Lemma
- Integral homology of a wedge of higher spheres has its cell basis Lemma
- Integral surface cup pairing from the oriented polygon Lemma
- Local sphere orientations and finite puncture excision Lemma
- One handle changes relative homology in one degree only Lemma
- Orientation reversal is the connected-sum inverse Lemma
- Relative homology of an h-cobordism vanishes at both ends Lemma
- Relative homology of the standard handle pair Lemma
- Relative homology over one base cell is shifted fiber homology Lemma
- Serre-fibration replacement preserves fiber homology transport Lemma
…and 36 more results.
Dependency tree · two levels
10 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
- Allen Hatcher, Algebraic Topology, Theorem 2.16 (standard reference, not scraped)