Basic Algebras
- Introduction
- Basic Algebras
- Creation
BasicAlgebra(Q): SeqEnum[Tup] → AlgBas
BasicAlgebra(F,R,s,P): AlgFr, SeqEnum, RngIntElt, SeqEnum → AlgBas
BasicAlgebra(F,R): AlgFr, SeqEnum → AlgBas
TensorProduct(A, B): AlgBas, AlgBas → AlgBas
BasicAlgebra(G, k): GrpPerm, FldFin → AlgBas
BasicAlgebra(G, k): GrpPC, FldFin → AlgBas
BasicAlgebra(G): GrpPerm → AlgBass
- Special Basic Algebras
BasicAlgebra(A): AlgMat → AlgBas
BasicAlgebraOfMatrixAlgebra(A): AlgMat → AlgBas
BasicAlgebraOfEndomorphismAlgebra(M): ModRng → AlgBas
BasicAlgebraOfHeckeAlgebra(G, H, F): GrpPerm, GrpPerm, FldFin) → AlgBas
BasicAlgebraOfHeckeAlgebra(G, H, F): GrpPC, GrpPC, FldFin → AlgBas
BasicAlgebraOfHeckeAlgebra(G, H, F): GrpAb, GrpAb, FldFin → AlgBas
BasicAlgebraOfSchurAlgebra(n, r, F): RngIntElt, RngIntElt, FldFin → AlgBas
BasicAlgebraOfGroupAlgebra(G,F): GrpPerm, FldFin → AlgBas
BasicAlgebraOfGroupAlgebra(G,F): GrpPC, FldFin → AlgBas
BasicAlgebraOfGroupAlgebra(G,F): GrpAb, FldFin → AlgBas
BasicAlgebra(S): SeqEnum → AlgBas
BasicAlgebraOfBlockAlgebra(S): SeqEnum → AlgBas
BasicAlgebraOfPrincipalBlock(G,k): GrpPerm, FldFin → AlgBas
BasicAlgebraOfExtAlgebra(A): AlgBas → AlgBas
BasicAlgebraOfExtAlgebra(A, n): AlgBas, RngIntElt → AlgBas
BasicAlgebraOfExtAlgebra(A): Rec → AlgBas
OppositeAlgebra(B): AlgBas → AlgBas
Example: Group Algebra
Example: Schur Algebra
- A Database of Basic Algebras
- Access Functions
- Elementary Operations
- Boolean Functions
- Homomorphisms
hom<A -> B | S>: AlgBas, AlgBas, ModMatFldElt → Map
Kernel(phi): Map → ModTupFld
Image(phi): Map → AlgBas, Map
IsAlgebraHomomorphism(A, B, psi): AlgBas, AlgBas, Mtrx → Bool
X * Y: Map, Map → Map
IsAlgebraHomomorphism(A, B, psi): AlgBas, AlgBas, Map → Bool
IsAlgebraHomomorphism(A, B, psi): AlgBasGrpP, AlgBasGrpP, Map → Bool
IsAlgebraHomomorphism(A, B, psi): AlgBasGrpP, AlgBas, Map → Bool
IsAlgebraHomomorphism(A, B, psi): AlgBas, AlgBasGrpP, Map → Bool
IsAlgebraHomomorphism(psi): Map → Bool
- Subalgebras and Quotient Algebras
- Subalgebras and their Constructions
sub<A | S>: AlgBas, SeqEnum → AlgBas, Map
SubalgebraFromBasis(A, V): AlgBas, SeqEnum → AlgBas, Map
MaximalIdempotent(A, S): AlgBas, SeqEnum → AlgBasElt
MinimalIdentity(A, S): AlgBas, SeqEnum[AlgBasElt] → AlgBasElt
Centre(A): AlgBas → AlgBas, Map
Centralizer(A,S): AlgBas, SeqEnum → AlgBas, Map
MaximalCommutativeSubalgebra(A,S): AlgBas, SeqEnum → AlgBas, Map
- Ideals and their Construction
ideal< A | S>: AlgBas, SeqEnum[AlgBasElt] → ModTupFld
ideal< A | S>: AlgBasGrpP, SeqEnum[AlgBasElt] → ModTupFld
LeftAnnihilator(A, S): AlgBas, SeqEnum[AlgBasElt] → SeqEnum[AlgBasElt]
RightAnnihilator(A, S): AlgBas, SeqEnum[AlgBasElt] → SeqEnum[AlgBaselt]
Annihilator(A,S): AlgBas, SeqEnum[AlgBasElt] → SeqEnum[AlgBasElt]
IsIdeal(A, S): AlgBas, ModTupFld → Bool
IsLeftIdeal(A,S): AlgBas, ModTupFld → Bool
IsRightIdeal(A, S): AlgBas, ModTupFld → Bool
RandomIdealGeneratedBy(A, n): AlgBas, RngIntElt → ModTupFld
- Quotient Algebras
- Units
- Minimal Forms and Gradings
MinimalGeneratorForm(A): AlgBas → Rec
MinimalGeneratorFormAlgebra(A): AlgBas → AlgBas
AssociatedGradedAlgebra(A): AlgBas → AlgBas
GradedCapHomomorphism(A): AlgBas → ModMatFldElt
GradedCapHomomorphism(A, B, mu): AlgBas, AlgBas, ModMatFldElt → ModMatFldElt
BuildHomomorphismFromGradedCap(A, B, phi): AlgBas, AlgBas, ModMatFldElt → ModMatFldElt
ChangeIdempotents(A, S): AlgBas, SeqEnum → AlgBas, Map
ChangeIdempotents(A, S): AlgBas, GrpPermElt → AlgBas, Map
Example: Graded Homomorphism
Example: GradedHomomorphisms 2
- Automorphisms and Isomorphisms
GradedAutomorphismGroupMatchingIdempotents(A): AlgBas → GrpMat, SeqEnum, SecEnum
GradedAutomorphismGroup(A): AlgBas → GrpMat, SeqEnum[ModMatFldElt], SeqEnum[ModMatFldElt], SeqEnum[ModMatFldElt]
IsGradedIsomorphic(A, B): AlgBas, AlgBas → Bool, ModMatFldElt
AutomorphismGroupMatchingIdempotents(A): AlgBas → AlgBas, ModMatFldElt
AutomorphismGroup(A): AlgBas → GrpMat, SeqEnum, SeqEnum, SeqEnum
InnerAutomorphismGroup(A): AlgBas → GrpMat
IsIsomorphic(A, B): AlgBas, AlgBas → Bool, Map
Example: Automorphism group
Example: modify presentation
Example: Graded Group Algebras
- Quiver and Relations
- Modules over Basic Algebras
- Indecomposable Projective Modules
ProjectiveModule(B, i): AlgBas, RngIntElt → ModRng
PathTree(B, i): AlgBas, RngIntElt → ModRng
ActionGenerator(B, i): AlgBas, RngIntElt → SeqEnum
IdempotentActionGenerators(B, i): AlgBas, RngIntElt → SeqEnum
NonIdempotentActionGenerators(B, i): AlgBas, RngIntElt → SeqEnum
Injection(B, i, v): AlgBas, RngIntElt, ModRngElt → AlgBasElt
- Creation
AModule(B, Q): AlgBas, SeqEnum[AlgMatElt] → ModRng
ProjectiveModule(B, S): AlgBas, SeqEnum[RngIntElt] → ModAlg, SeqEnum, SeqEnum
IrreducibleModule(B, i): AlgBas, RngIntElt → ModAlg
SimpleModule(B, i): AlgBas, RngIntElt → ModAlg
ZeroModule(B): AlgBas → ModAlg
RightRegularModule(B): AlgBas → ModAlg
RegularRepresentation(v): AlgBasElt → AlgMatElt
Restriction(M, B, xi): ModAlgBas, AlgBas, ModMatFldElt → ModAlgBas
ChangeAlgebra(M, B, xi): ModAlgBas, AlgBas, Map → ModAlgBas
ChangeAlgebra(M, B, xi): ModAlgBas, AlgBas, ModMatFldElt → ModAlgBas
JacobsonRadical(M): ModAlg → ModAlg
Socle(M): ModAlg → ModAlg
- Access Functions
- Predicates
- Elementary Operations
- Homomorphisms of Modules
- Creation
AHom(M, N): ModAlg, ModAlg → ModMatFld
PHom(M,N): ModAlg, ModAlg → ModMatFld
ZeroMap(M, N): ModAlg, ModAlg → ModMatFld
LiftHomomorphism(x, n): ModAlgElt, RngIntElt → ModMatFldElt
LiftHomomorphism(X, N): SeqEnum[ModAlgElt], SeqEnum[RngIntElt] → ModMatFldElt
Pushout(M, f1, N1, f2, N2): ModAlg, ModMatFldElt, ModAlg, ModMatFldElt, ModAlg → ModAlg, ModMatFldElt, ModMatFldElt
Pullback(f1, M1, f2, M2, N): ModAlg, ModMatFldElt, ModAlg, ModMatFldElt, ModAlg → ModAlg, ModMatFldElt, ModMatFldElt
- Access Functions
- Projective Covers and Resolutions
ProjectiveCover(M): ModAlg → ModAlg, ModMatFldElt, SeqEnum[ModMatFldElt], SeqEnum[ModMatFldElt], SeqEnum[RngIntElt]
ProjectiveResolution(M, n): ModAlg, RngIntElt → ModCpx, ModMatFldElt
CompactProjectiveResolution(M, n): ModAlg, RngIntElt → Rec
CompactProjectiveResolutionsOfSimpleModules(A,n): AlgBas, RngIntElt → SeqEnum
SyzygyModule(M, n): ModAlg, RngIntElt → ModAlg
SimpleHomologyDimensions(M): ModAlg → SeqEnum
Example: Homomorphisms
Example: Homomorphisms 2
- Duals and Injectives
Dual(M): ModAlg → ModAlg
BaseChangeMatrix(A): AlgBas → ModAlg
- Injective Modules
InjectiveModule(B, i): AlgBas, RngIntElt → ModAlg
InjectiveHull(M): ModAlg → ModAlg, ModMatFldElt, SeqEnum[ModMatFldElt], SeqEnum[ModMatFldElt], SeqEnum[RngIntElt]
InjectiveResolution(M, n): ModAlg, RngIntElt → ModCpx, ModMatFldElt
CompactInjectiveResolution(M, n): ModAlg, RngIntElt → Rec
InjectiveSyzygyModule(M, n): ModAlg, RngIntElt → ModAlg
SimpleCohomologyDimensions(M): ModAlg → SeqEnum
Example: Opposite
- Cohomology
CohomologyRingGenerators(P): Rec → Rec
CohomologyRightModuleGenerators(P, Q, CQ): Rec, Rec, Rec → Rec
CohomologyLeftModuleGenerators(P, CP, Q): Tup, Tup, Tup → Tup
DegreesOfCohomologyGenerators(C): Rec → SeqEnum
CohomologyGeneratorToChainMap(P,Q,C,n): ModCpx, ModCpx, Rec, RngIntElt → MapChn
CohomologyGeneratorToChainMap(P, C, n): ModCpx, Tup, RngIntElt → MapChn
Example: Cohomology 2
- Ext-Algebras
- Group Algebras of \(p\)-groups
- Access Functions
- Projective Resolutions
- Cohomology Generators
- Cohomology Rings
- Restrictions and Inflations
RestrictionData(A,B): AlgBasGrpP, AlgBasGrpP → ModMatFldElt, ModMatFldElt, SeqEnum
RestrictResolution(PR, RD): Rec, Rec → ModCpx
RestrictionChainMap(P1,P2): Rec, Rec → MapChn
RestrictionOfGenerators({PR1, PR2, AC1,}{ AC2, REL2}): Rec, Rec, Rec, Rec, Rec → SeqEnum
InflationMap({PR2, PR1, AC2, AC1,}{ REL1, theta}): Rec, Rec, Rec, Rec, Rec → SeqEnum
Example: Cohomology Ring
- A-infinity Algebra Structures on Group Cohomology
AInfinityRecord(G,n): Grp, RngIntElt → Rec
MasseyProduct(Aoo,terms): Rec, SeqEnum[RngElt] → RngElt
HighProduct(Aoo,terms): Rec, SeqEnum[RngElt] → RngElt
HighMap(Aoo,terms): Rec, SeqEnum[RngElt] → MapChn
Example: A-infinity mod 2
Example: A-infinity mod 3
- Homological Algebra Toolkit
ActionMatrix(A,x): AlgBas, Mtrx → ModMatFldElt
CohomologyRingQuotient(CR): Rec → Rng, Map
LiftToChainmap(P,f,d): ModCpx, Mtrx, RngIntElt → MapChn
NullHomotopy(f): MapChn → MapChn
IsNullHomotopy(f,H): MapChn, MapChn → BoolElt
ChainmapToCohomology(f,CR): MapChn, Rec → RngElt
CohomologyToChainmap(xi,CR,P): RngElt, Rec, ModCpx → MapChn
Example: Nullhomotopy