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.
Natural isomorphism
Definition
A natural isomorphism is a natural transformation for which there is a natural transformation with and . The compositions here are the vertical compositions of Identity natural transformation and vertical composition.
When the source category is small, so that Functor category is formed, this says exactly that is an isomorphism from to in that functor category. Thus the definition combines Natural transformation and its components with the categorical notion of isomorphism from Isomorphism, groupoid, and connected category without requiring a functor category for an arbitrary large source.
Depends on
Used by
- Additive cocontinuous module functors admit right adjoints Corollary
- Eilenberg-Watts is a schematic equivalence of Hom categories Corollary
- Finite Eilenberg–Watts is a biequivalence Corollary
- Graded bimodule maps classify shift-compatible transformations Corollary
- Objects a and b are isomorphic exactly when C(-,a) and C(-,b) are naturally isomorphic Corollary
- The center is Morita invariant, via natural endomorphisms of the identity Corollary
- The left-to-right exact equivalence need not preserve the identity Counterexample
- Weak actions do not supply pentagon coherence data Counterexample
- Bicategories, pseudofunctors, and biequivalences Definition
- Braiding Definition
- Coherent action of a group on a category Definition
- Coherently shift-compatible functors and natural transformations Definition
- Equivalence, quasi-inverse, and adjoint equivalence of categories Definition
- Exact functor between triangulated categories Definition
- Faithful weak action Definition
- Lax, strong, and strict monoidal functors Definition
- Localization of a category at a class of morphisms Definition
- Monoidal category Definition
- Preservation, reflection, and creation of limits and colimits; continuous and cocontinuous functors Definition
- Presheaves, covariantly and contravariantly representable functors, and representations Definition
- The category of right-module endofunctors Definition
- Weak action of a group on a category Definition
- Open-set and closed-set functors on Topᵒᵖ are naturally isomorphic by complements Example
- The distributive and exponential laws of sets are natural isomorphisms Example
- The kernel end and coend distinguish the regular and co-regular bimodules Example
- The opposite-group functor is naturally isomorphic to the identity functor by inversion Example
- Bilinear right exact functors are determined by their value on the regular modules Lemma
- Coherently shift-compatible functors and transformations form k-linear hom categories Lemma
- Finite Eilenberg–Watts kernels: explicit end and coend universal maps Lemma
- Finite module duality is exact with commuting bimodule actions Lemma
- Finite vector-space copowers in a k-linear abelian category Lemma
- Homogeneous free presentations prove the graded comparison is an isomorphism Lemma
- Nakayama kernels give well-defined adjoint functors Lemma
- Shift signs and exact-functor maps on triangulated K0 Lemma
- A natural transformation is a natural isomorphism exactly when every component is an isomorphism Proposition
- A translation-compatible natural isomorphism of exact functors respects triangles Proposition
- Equivalences preserve, reflect, and create limits and colimits in the isomorphism-invariant sense Proposition
- The left-to-right exact equivalence sends the identity to the Nakayama functor Proposition
- The projective Nakayama pairing and the symmetric-algebra specialization Proposition
- A category with finite products is monoidal Theorem
…and 8 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
- Emily Riehl, Category Theory in Context, Chapter 1 (standard reference, not scraped)