UOR Cohomology

IRI
https://uor.foundation/cohomology/
Prefix
cohomology:
Space
bridge
Comment
Cochain complexes, sheaf cohomology, and local-to-global obstruction detection.

Imports

  • https://uor.foundation/schema/
  • https://uor.foundation/homology/
  • https://uor.foundation/resolver/
  • https://uor.foundation/observable/
  • https://uor.foundation/partition/

Classes

NameIRISubclass OfDisjoint WithComment
CochainGrouphttps://uor.foundation/cohomology/CochainGrouphttp://www.w3.org/2002/07/owl#ThingA cochain group: the dual of a chain group, maps chains to coefficients.
CoboundaryOperatorhttps://uor.foundation/cohomology/CoboundaryOperatorhttp://www.w3.org/2002/07/owl#ThingThe coboundary operator δ^k: C^k → C^{k+1}. Satisfies δ² = 0.
CochainComplexhttps://uor.foundation/cohomology/CochainComplexhttp://www.w3.org/2002/07/owl#ThingA cochain complex: a sequence of cochain groups connected by coboundary operators.
CohomologyGrouphttps://uor.foundation/cohomology/CohomologyGrouphttp://www.w3.org/2002/07/owl#ThingThe k-th cohomology group H^k = ker(δ^k) / im(δ^{k-1}). Measures k-dimensional obstructions.
Sheafhttps://uor.foundation/cohomology/Sheafhttp://www.w3.org/2002/07/owl#ThingA sheaf F over a simplicial complex: assigns data to each simplex with restriction maps.
Stalkhttps://uor.foundation/cohomology/Stalkhttp://www.w3.org/2002/07/owl#ThingA stalk F_σ: the local data of a sheaf at a simplex σ.
Sectionhttps://uor.foundation/cohomology/Sectionhttp://www.w3.org/2002/07/owl#ThingA global section of a sheaf: a consistent choice of local data across all simplices.
LocalSectionhttps://uor.foundation/cohomology/LocalSectionhttps://uor.foundation/cohomology/SectionA local section: a consistent choice of data over a subcomplex.
RestrictionMaphttps://uor.foundation/cohomology/RestrictionMaphttp://www.w3.org/2002/07/owl#ThingA restriction map ρ_{σ,τ}: maps data from a simplex to a face.
GluingObstructionhttps://uor.foundation/cohomology/GluingObstructionhttp://www.w3.org/2002/07/owl#ThingA gluing obstruction: a cohomology class that detects when local sections fail to glue.

Properties

NameKindFunctionalDomainRangeComment
cochainDegreeDatatypetruehttps://uor.foundation/cohomology/CochainGrouphttp://www.w3.org/2001/XMLSchema#integerThe degree k of this cochain group C^k.
cochainRankDatatypetruehttps://uor.foundation/cohomology/CochainGrouphttp://www.w3.org/2001/XMLSchema#nonNegativeIntegerThe rank (dimension) of this cochain group.
dualOfObjecttruehttps://uor.foundation/cohomology/CochainGrouphttps://uor.foundation/homology/ChainGroupThe chain group that this cochain group is dual to.
coboundarySourceObjecttruehttps://uor.foundation/cohomology/CoboundaryOperatorhttps://uor.foundation/cohomology/CochainGroupThe source cochain group of this coboundary operator.
coboundaryTargetObjecttruehttps://uor.foundation/cohomology/CoboundaryOperatorhttps://uor.foundation/cohomology/CochainGroupThe target cochain group of this coboundary operator.
satisfiesCoboundarySquaredZeroDatatypetruehttps://uor.foundation/cohomology/CoboundaryOperatorhttp://www.w3.org/2001/XMLSchema#booleanWhether this coboundary operator satisfies δ² = 0.
hasCochainGroupObjectfalsehttps://uor.foundation/cohomology/CochainComplexhttps://uor.foundation/cohomology/CochainGroupA cochain group belonging to this cochain complex.
hasCoboundaryObjectfalsehttps://uor.foundation/cohomology/CochainComplexhttps://uor.foundation/cohomology/CoboundaryOperatorA coboundary operator belonging to this cochain complex.
cohomologyDegreeDatatypetruehttps://uor.foundation/cohomology/CohomologyGrouphttp://www.w3.org/2001/XMLSchema#integerThe degree k of this cohomology group H^k.
cohomologyRankDatatypetruehttps://uor.foundation/cohomology/CohomologyGrouphttp://www.w3.org/2001/XMLSchema#nonNegativeIntegerThe rank (dimension) of this cohomology group.
sheafOverObjecttruehttps://uor.foundation/cohomology/Sheafhttps://uor.foundation/homology/SimplicialComplexThe simplicial complex that this sheaf is defined over.
coefficientInObjecttruehttps://uor.foundation/cohomology/Sheafhttps://uor.foundation/schema/RingThe coefficient ring of this sheaf.
hasStalksObjectfalsehttps://uor.foundation/cohomology/Sheafhttps://uor.foundation/cohomology/StalkA stalk belonging to this sheaf.
stalkAtObjecttruehttps://uor.foundation/cohomology/Stalkhttps://uor.foundation/homology/SimplexThe simplex at which this stalk is located.
restrictsFromObjecttruehttps://uor.foundation/cohomology/RestrictionMaphttps://uor.foundation/homology/SimplexThe source simplex of this restriction map.
restrictsToObjecttruehttps://uor.foundation/cohomology/RestrictionMaphttps://uor.foundation/homology/SimplexThe target simplex (face) of this restriction map.
hasGlobalSectionObjectfalsehttps://uor.foundation/cohomology/Sheafhttps://uor.foundation/cohomology/SectionA global section of this sheaf.
obstructionClassObjecttruehttps://uor.foundation/cohomology/GluingObstructionhttps://uor.foundation/cohomology/CohomologyGroupThe cohomology class that this gluing obstruction represents.
addressesSuggestionObjectfalsehttps://uor.foundation/cohomology/GluingObstructionhttps://uor.foundation/resolver/RefinementSuggestionThe refinement suggestion that, if applied, would resolve this gluing obstruction. Computed by the kernel when ψ₆ detects H^1 ≠ 0: the obstruction class indexes the site pair that is incompatible, and the suggestion targets that pair with a new bridging constraint.
sheafAnalysisObjecttruehttps://uor.foundation/resolver/ResolutionStatehttps://uor.foundation/cohomology/SheafThe sheaf analysis associated with a resolution state.

Named Individuals

NameTypePropertiesComment
coboundarySquaredZerohttps://uor.foundation/op/Identity
  • lhs: https://uor.foundation/schema/term_coboundarySquaredZero_lhs
  • rhs: https://uor.foundation/schema/term_coboundarySquaredZero_rhs
  • forAll: https://uor.foundation/schema/term_coboundarySquaredZero_forAll
  • verificationDomain: https://uor.foundation/op/Topological
δ² = 0: the coboundary of a coboundary is zero.
deRhamDualityhttps://uor.foundation/op/Identity
  • lhs: https://uor.foundation/schema/term_deRhamDuality_lhs
  • rhs: https://uor.foundation/schema/term_deRhamDuality_rhs
  • forAll: https://uor.foundation/schema/term_deRhamDuality_forAll
  • verificationDomain: https://uor.foundation/op/Topological
Discrete de Rham duality: H^k ≅ Hom(H_k, R).
sheafCohomologyBridgehttps://uor.foundation/op/Identity
  • lhs: https://uor.foundation/schema/term_sheafCohomologyBridge_lhs
  • rhs: https://uor.foundation/schema/term_sheafCohomologyBridge_rhs
  • forAll: https://uor.foundation/schema/term_sheafCohomologyBridge_forAll
  • verificationDomain: https://uor.foundation/op/Topological
Sheaf cohomology equals simplicial cohomology for constant sheaves.
localGlobalPrinciplehttps://uor.foundation/op/Identity
  • lhs: https://uor.foundation/schema/term_localGlobalPrinciple_lhs
  • rhs: https://uor.foundation/schema/term_localGlobalPrinciple_rhs
  • forAll: https://uor.foundation/schema/term_localGlobalPrinciple_forAll
  • verificationDomain: https://uor.foundation/op/Topological
Local-global principle: H^1(K; F) = 0 implies all local sections glue to global sections.