Schemes
- Introduction and First Examples
- Ambients
- Affine and Projective Spaces
AffineSpace(k,n): Rng, RngIntElt → Aff
ProjectiveSpace(k,n): Rng, RngIntElt → Prj
ProjectiveSpace(k,W): Rng, [RngIntElt] → Prj
ProjectiveLine(k): RngIntRes → SetIndx, UserProgram
ProjectiveLine(k): RngOrdRes → SetIndx, UserProgram
ProjectiveLineProcess(V): ModTupFld[FldFin] → ProcPL
ProjectiveLineProcess(k, n): FldFin, RngIntElt → ProcPL
# P: ProcPL → RngIntElt
Next(P): ProcPL → ModTupFldElt
AffineSpace(R): RngMPol → Aff
Spec(R): RngMPol → Aff
ProjectiveSpace(R): RngMPol → Prj
Proj(R): RngMPol → Prj
AssignNames(~A,N): Sch, [MonStgElt]
A . i: Sch, RngIntElt → RngMPolElt
Name(A,i): Sch, RngIntElt → RngMPolElt
Example: Affine Space Names
A eq B: Sch, Sch → BoolElt
- Scrolls and Products
DirectProduct(A,B): Sch, Sch → Sch, SeqEnum
RuledSurface(k,a,b): Rng, RngIntElt, RngIntElt → PrjScrl
RuledSurface(k,n): Rng, RngIntElt → PrjScrl
AbsoluteRationalScroll(k,N): Rng, SeqEnum → PrjScrl
ProductProjectiveSpace(k,N): Rng, SeqEnum → PrjScrl
SegreProduct(Xs): SeqEnum[Sch] → Sch, SeqEnum
SegreEmbedding(X): Sch → Sch, MapIsoSch
Example: Sch:segre Embedding
- Functions and Homogeneity on Ambient Spaces
- Prelude to Points
A ! [a,b,...]: Sch, [RngElt] → Pt
A(L) ! [a,b,...]: SetPt, [RngElt] → Pt
Example: Schemes Points Example1
Origin(A): Aff → Pt
Simplex(A): Prj → SeqEnum
Coordinates(p): Pt → SeqEnum
p[i]: Pt, RngIntElt → RngElt
Coordinate(p,i): Pt, RngIntElt → SeqEnum
p @ f: Pt, FldFunFracSchElt → RngElt
f(p): Pt, FldFunFracSchElt → RngElt
Evaluate(f, p): RngElt, Pt → RngElt
Example: Evaluate Funfld Example
- Constructing Schemes
Scheme(X,f): Sch, RngMPolElt → Sch
Scheme(X,F): Sch, SeqEnum → Sch
Scheme(X,I): Sch, RngMPol → Sch
Scheme(X,Q): Sch, RngMPolRes → Sch
Cluster(X,f): Sch, RngMPolElt → Clstr
Cluster(X,F): Sch, SeqEnum → Clstr
Cluster(X,I): Sch, RngMPol → Clstr
Cluster(X,Q): Sch, RngMPolRes → Clstr
Example: Schemes Creation
Spec(R): RngMPolRes → Sch, Aff
Proj(R): RngMPolRes → Sch, Prj
EmptyScheme(X): Sch → Sch
EmptySubscheme(X): Sch → Sch, MapSch
X meet Y: Sch, Sch → Sch
Intersection(X,Y): Sch, Sch → Sch
X join Y: Sch, Sch → Sch
Union(X,Y): Sch, Sch → Sch
& join S: [Sch] → Sch
Difference(X, Y): Sch, Sch → Sch
Complement(X, Y): Sch, Sch → Sch
RemoveLinearRelations(X): Sch → Sch, MapIsoSch
Blowup(X,Y): Sch, Sch → Sch, MapSch
Blowup(X,p): Sch, Pt → Sch, MapSch
LocalBlowUp(X,Y): Sch, Sch → SeqEnum
Example: remove
Example: Sch Blowup Ex
Saturate(~X): Sch
AssignNames(~X,N): Sch, SeqEnum
X . i: Sch, RngIntElt → RngMPolElt
Name(X,i): Sch, RngIntElt → RngMPolElt
- Different Types of Scheme
- Basic Attributes of Schemes
- Function Fields and their Elements
Scheme(F): FldFunFracSch → Sch
IntegerRing(F): RngFrac → Rng
Integers(F): RngFrac → Rng
AssignNames(~F, S): RngFrac, [MonStgElt]
F ! g: FldFunFracSch, RngElt → FldFunFracSchElt
F . i: FldFunFracSch, RngIntElt → FldFunFracSchElt
ProjectiveFunction(f): FldFunFracSchElt → FldFracElt
ProjectiveRationalFunction(f): FldFunFracSchElt → FldFunRatMElt
RestrictionToPatch(f, Xi): FldFunFracSchElt, Sch → FldFracElt
Numerator(f): RngFracElt → RngElt
Denominator(f): RngFracElt → RngElt
f * g: RngFracElt, RngFracElt → RngFracElt
f + g: RngFracElt, RngFracElt → RngFracElt
f - g: RngFracElt, RngFracElt → RngFracElt
- f: RngFracElt → RngFracElt
f / g: RngFracElt, RngFracElt → RngFracElt
f ^ n: RngFracElt, RngIntElt → RngFracElt
f eq g: RngFracElt, RngFracElt → BoolElt
IsZero(f): RngFracElt → BoolElt
IsOne(f): RngFracElt → BoolElt
IsMinusOne(f): RngFracElt → BoolElt
IsUnit(f): RngFracElt → BoolElt
IntegralSplit(f, X): FldFunFracSchElt, Sch → RngMPolElt, RngMPolElt
Numerator(f, X): FldFunFracSchElt, Sch → MPolElt
Denominator(f, X): FldFunFracSchElt, Sch → MPolElt
Example: Scheme Fld Fun Elt
Restriction(f, Y): FldFunFracSchElt, Sch → FldFunFracSchElt
GenericPoint(X): Sch → Pt
- Rational Points and Point Sets
X(L): Sch, Rng → SetPt
PointSet(X,L): Sch, Rng → SetPt
X(m): Sch, Map → SetPt
PointSet(X,m): Sch, Map → SetPt
P eq Q: SetPt, SetPt → BoolElt
Scheme(P): SetPt → Sch
Curve(P): SetPt → Crv
Ring(P): SetPt → Rng
RingMap(P): SetPt → Map
X ! Q: Sch, SeqEnum → Pt
X(L) ! Q: SetPt, SeqEnum → Pt
p eq q: Pt, Pt → BoolElt
p in X: Pt, Sch → BoolElt
Scheme(p): Pt → Sch
Curve(p): Pt → Crv
Q in X: SeqEnum, Sch → BoolElt
S subset X: Setq, Sch → BoolElt
RationalPoints(X): Sch → SetIndx
RationalPoints(X,L): Sch, Rng → SetIndx
Points(X): Sch → SetIndx
Points(X,L): Sch, Rng → SetIndx
RationalPointsByFibration(X): Sch → SetIndx
Random(S): SetPt → Pt
HasNonsingularPoint(X): Sch → BoolElt, Pt
HasNonsingularPoint(X,L): Sch, FldFin → BoolElt, Pt
PointsModPN(S, P, N): Sch, ., RngIntElt → SetIndx
PointsModPN(S, M): Sch, RngIntElt → SetIndx
PointsModPN(S, M): Sch, RngOrdIdl → SetIndx
Example: Scheme Points
- Zero-dimensional Schemes
Cluster(p): Pt → Clstr
Cluster(X, p): Sch, Pt → Clstr;
Cluster(S): SetEnum → Clstr
Cluster(S): SetIndx → Clstr
Cluster(X, S): Sch, SetEnum → Clstr
Cluster(X, S): Sch, SetIndx → Clstr
RationalPoints(Z): Sch → SetEnum
RationalPoints(Z,L): Sch, Rng → SetEnum
PointsOverSplittingField(Z): Clstr → SetEnum
HasPointsOverExtension(X): Sch → BoolElt
HasPointsOverExtension(X,L): Sch, Rng → BoolElt
Degree(Z): Clstr → RngIntElt
Example: Cluster Degree5
- Local Geometry of Schemes
- Point Conditions
- Point Computations
- Analytically Hypersurface Singularities
IsHypersurfaceSingularity(p,prec): Pt, RngIntElt → BoolElt, RngMPolElt, SeqEnum, Rec
HypersurfaceSingularityExpandFurther(dat,prec,R): Rec, RngIntElt, RngMPol → RngMPolElt
HypersurfaceSingularityExpandFunction(dat,f,prec,R): Rec, FldFunRatMElt, RngIntElt, RngMPol → RngMPolElt, RngMPolElt
MilnorNumberAnalyticHypersurface(dat): Rec → RngIntElt
TjurinaNumberAnalyticHypersurface(dat): Rec → RngIntElt
Example: An Hyp Sing Ex
- Classification and Normal Forms of Singularities
- Global Geometry of Schemes
- Base Change for Schemes
BaseChange(A,K): Sch, Rng → Sch
BaseExtend(A,K): Sch, Rng → Sch
BaseChange(A,m): Sch, Map → Sch
BaseExtend(A,m): Sch, Map → Sch
BaseChange(F,K): SeqEnum, Rng → SeqEnum
BaseExtend(F,K): SeqEnum, Rng → SeqEnum
BaseChange(F,m): SeqEnum, Rng → SeqEnum
BaseExtend(F,m): SeqEnum, Rng → SeqEnum
BaseChange(X,A): Sch, Sch → Sch
BaseExtend(X,A): Sch, Sch → Sch
BaseChange(X,A,m): Sch, Sch, Map → Sch
BaseExtend(X,A,m): Sch, Sch, Map → Sch
BaseChange(X, n): Sch, RngIntElt → Sch
BaseExtend(X, n): Sch, RngIntElt → Sch
Example: Base Change Schemes
- Affine Patches and Projective Closure
ProjectiveClosure(X): Sch → Sch
AffinePatch(X,i): Sch, RngIntElt → Sch
AffinePatch(X,p): Sch, Pt → Sch, Pt
IsStandardAffinePatch(A): Aff → BoolElt, RngIntElt
NumberOfAffinePatches(X): Sch → BoolElt
HasAffinePatch(X, i): Sch, RngIntElt → BoolElt
WeightedAffinePatch(P, i): Prj, RngIntElt → Sch, MapIsoSch
Example: Projective Closure
Example: Projective Closure Incorrect
Example: Weighted Patches
HyperplaneAtInfinity(X): Sch → Sch
ProjectiveClosureMap(A): Aff → MapSch
PCMap(A): Aff → MapSch
AffineDecomposition(P): Prj → [MapSch], Pt
CentredAffinePatch(S, p): Sch, Pt → Sch, MapSch
- Arithmetic Properties of Schemes and Points
- Height
- Restriction of Scalars
RestrictionOfScalars(S, F): Sch, Fld → Sch, MapSch, UserProgram, Map
WeilRestriction(S, F): Sch, Fld → Sch, MapSch, UserProgram, Map
- Local Solubility
IsEmpty(Xm): SetPt → BoolElt, Pt
Example: anf1
Example: anf2
IsLocallySolvable(X, p): Sch, RngOrdIdl → BoolElt, Pt
IsLocallySolvable(X, p): Sch, RngIntElt → BoolElt, Pt
IsLocallySolvable(X,pl): Sch, PlcFunElt → BoolElt, Pt
Example: Anf Local Solv
LiftPoint(P, n): Pt, RngIntElt → Pt
LiftPoint(F, d, P, n): [RngMPolElt], RngIntElt, [FldLocElt], RngIntElt → SeqEnum
Example: Anf Lift
- Searching for Points
- Reduction Mod \(p\)
- Maps between Schemes
- Creation of Maps
map< X -> Y | F >: Sch, Sch, SeqEnum → MapSch
map< X -> Y | F, G >: Sch, Sch, SeqEnum → MapSch
map< X -> Y | u, F >: Sch, Sch, Map, SeqEnum → MapSch
iso< X -> Y | F, G >: Sch, Sch, SeqEnum, SeqEnum → MapAutSch
Example: Map Creation
Example: Map Fnfld
Example: Map Frobenius
IdentityMap(X): Sch → MapSch
ConstantMap(X,Y,p): Sch, Sch, Pt → MapSch
map< X -> Y | Q >: Sch, Sch, SeqEnum → MapSch
Projection(X,Y): Prj, Prj → MapSch
Projection(X, Q): Sch, Prj → Sch, MapSch
Projection(X): Sch → Sch, MapSch
Projection(X, p): Sch, Pt → Sch, MapSch
ProjectionFromNonsingularPoint(X,p): Sch, Pt → Sch, MapSch, Sch
ProjectiveMap(L, Y): [FldFunFracSchElt], Sch → MapSch
ProjectiveMap(L): [FldFunFracSchElt] → MapSch
ProjectiveMap(f, Y): FldFunFracSchElt, Sch → MapSch
ProjectiveMap(f): FldFunFracSchElt → MapSch
Example: Map Creation Prj
Elimination(X,V): Sch, SeqEnum → Sch
Inverse(f): MapSch → MapSch
IsInvertible(f): MapSch → Bool, MapSch
HasKnownInverse(f): MapSch → Bool
Example: Map Creation Inv
g * f: MapSch, MapSch → MapSch
Components(f): Map → [Map]
Example: Hom Spaces
Restriction(f,X,Y): MapSch, Sch, Sch → MapSch
Expand(phi): MapSch → MapSch
Extend(phi): MapSch → MapSch
Prune(phi): MapSch → MapSch
Normalization(phi): MapSch → MapSch
Normalisation(phi): MapSch → MapSch
Example: Map Creation Comp Alt
ImproveParametrization(p): MapSch → MapSch
Example: Improve Prm Ex
- Basic Attributes
- Maps and Points
- Maps and Schemes
Pullback(f, X): MapSch, Sch → Sch
X @@ f: Sch, MapSch → Sch
Image(f): MapSch → Sch
f(X): Sch, MapSch → Sch
Image(f,X,d): MapSch, Sch, RngIntElt → []
Example: Map Image1
Example: Map Image2
BaseScheme(f): MapSch → Sch
BasePoints(f): MapSch → SetEnum
BasePoints(f,L): MapSch, Fld → SetEnum
Example: Map Base Points
Example: Scroll Map Base Points
- Maps and Closure
ProjectiveClosure(f): MapSch → MapSch
MakeProjectiveClosureMap(A, P, S): Aff, Prj, SeqEnum
MakePCMap(A, P, S): Aff, Prj, SeqEnum
MakeProjectiveClosureMap(m): Map
MakePCMap(m): Map
RestrictionToPatch(f,j): MapSch, RngIntElt → MapSch
RestrictionToPatch(f,i,j): MapSch, RngIntElt, RngIntElt → MapSch
Example: Map Patches
- Automorphisms
Automorphism(X,F): Sch, SeqEnum → MapAutSch
IdentityAutomorphism(X): Sch → MapAutSch
IdentityMap(X): Sch → MapAutSch
IsEndomorphism(f): MapSch → BoolElt
IsAutomorphism(f): MapSch → BoolElt, AutSch
Example: Automorphism Construction
Example: Aut Aff Jac
- Affine Automorphisms
Automorphism(A,F): Sch, SeqEnum → MapSch
Automorphism(A,M): Sch, Mtrx → MapIsoSch
Translation(A,p): Sch, Pt → MapSch
PermutationAutomorphism(A, g): Sch, GrpPermElt → MapIsoSch
Automorphism(A, g): Sch, GrpPermElt → MapIsoSch
Example: Aut Aff Perm
Automorphism(A,p): Sch, RngMPolElt → IsoSch
AffineDecomposition(f): MapSch → MapSch, MapSch
Example: Decompose Automorphism
NagataAutomorphism(A): Aff → MapSch
Projectivity(A,M): Aff, Mtrx → MapAutSch
Example: projectivity
- Projective Automorphisms
Automorphism(P,F): Prj, SeqEnum → MapSch
Matrix(f): MapSch → Mtrx
Automorphism(P,M): Sch, Mtrx → MapSch
Aut(P): Prj → PowAutSch
AutomorphismGroup(P): Prj → GrpMat, Map
Example: Projective Automorphism Group
TranslationOfSimplex(P,Q): Prj, [Pt] → MapSch
Translation(P,Q): Prj, [Pt] → MapSch
Translation(P,p,q): Prj, Pt, Pt → MapSch
Translation(X,p): Sch, Pt → MapSch
Example: translation
QuadraticTransformation(P): Prj → MapSch
QuadraticTransformation(P,Q): Prj, SeqEnum → MapSch
QuadraticTransformation(X): Sch → Sch, MapIsoSch
QuadraticTransformation(X,Q): Sch, [Pt] → Sch, MapIsoSch
Example: Cremona Factorisation
- Scheme Graph Maps
- Tangent and Secant Varieties and Isomorphic Projections
- Linear Systems
- Creation of Linear Systems
- Explicit Creation
LinearSystem(P, d): Sch, RngIntElt → LinearSys
LinearSystem(P, d): Sch, [RngIntElt] → LinearSys
LinearSystem(P, F): Sch, SeqEnum[RngMPolElt] → LinearSys
MonomialsOfWeightedDegree(X, D): Sch, [RngIntElt] → SetIndx
Example: Linsys Construction
ImageSystem(f,S,d): MapSch, Sch, RngIntElt → LinearSys
Example: Image Finder
- Geometric Restrictions: Points
LinearSystem(L, p): LinearSys, Point → LinearSys
LinearSystem(L, P): LinearSys, SeqEnum[Point) → LinearSys
Example: subsystems
LinearSystem(L, p, m): LinearSys, Point, RngIntElt → LinearSys
LinearSystem(L, P, M): LinearSys, SeqEnum[Point), SeqEnum(RngIntElt) → LinearSys
Example: Subsystems Mult
Example: Subsystems Speed
- Geometric Restrictions: Schemes
- Geometric Restrictions: Affine Plane Curves with Non-ordinary Singularities
LinearSystem(L, p, m, t): LinearSys, Point, SeqEnum, SeqEnum[SeqEnum]) → LinearSys
LinearSystem(L, P, M, T): LinearSys, Points, SeqEnum[SeqEnum], SeqEnum[SeqEnum[SeqEnum]]) → LinearSys
Example: tacnode
Example: quadrifolium
Example: Cusp Sing
Example: Two Cubics
Example: Pencil Curves
- Geometric Restrictions: Trace on a Scheme
- Explicit Restrictions
- Basic Algebra of Linear Systems
- Tests for Linear Systems
- Geometrical Properties
- Linear Algebra
CoefficientSpace(L): LinearSys → ModTupFld
CoefficientMap(L): LinearSys → ModTupFldElt
PolynomialMap(L): LinearSys → RngMPolElt
Complement(L,K): LinearSys, LinearSys → LinearSys
Complement(L,X): LinearSys, Sch → LinearSys
Example: Creation By Subspace
L meet K: LinearSys, LinearSys → LinearSys
Intersection(L,K): LinearSys, LinearSys → LinearSys
X in L: Sch, LinearSys → BoolElt
f in L: RngMPolElt, LinearSys → BoolElt
K subset L: LinearSys, LinearSys → BoolElt
IsSubsystem(L,K): LinearSys, LinearSys → BoolElt
- Linear Systems and Maps
- Divisors
- Divisor Groups
- Creation Of Divisors
Divisor(X,f): Sch, FldFunFracSchElt → DivSchElt
Divisor(X,f): Sch, FldFunRatMElt → DivSchElt
Divisor(X,f): Sch, RngMPolElt → DivSchElt
Divisor(X,Q): Sch, SeqEnum → DivSchElt
Divisor(X,Y): Sch, Sch → DivSchElt
Divisor(X,I): Sch, RngMPol → DivSchElt
HyperplaneSectionDivisor(X): Sch → DivSchElt
ZeroDivisor(X): Sch → DivSchElt
CanonicalDivisor(X): Sch → DivSchElt
SheafToDivisor(S): ShfCoh → DivSchElt
RoundDownDivisor(D): DivSchElt → DivSchElt
RoundUpDivisor(D): DivSchElt → DivSchElt
FractionalPart(D): DivSchElt → DivSchElt
IntegralMultiple(D): DivSchElt → DivSchElt, RngIntElt
EffectiveHypersurfaceTwist(D): DivSchElt → DivSchElt, RngMPolElt
- Ideals and Factorisations
- Basic Divisor Predicates
- Arithmetic of Divisors
- Further Divisor Properties
IsCanonical(D): DivSchElt → BoolElt
IsAnticanonical(D): DivSchElt → BoolElt
IsCanonicalWithTwist(D): DivSchElt → BoolElt, RngIntElt
IsPrincipal(D): DivSchElt → BoolElt, FldFunFracSchElt
IsCartier(D): DivSchElt → BoolElt
Example: Divs Cartier Ex
IsLinearlyEquivalent(D,E): DivSchElt, DivSchElt → BoolElt, FldFunFracSchElt
BaseLocus(D): DivSchElt → Sch
IsBasePointFree(D): DivSchElt → BoolElt
IsMobile(D): DivSchElt → BoolElt
IntersectionNumber(D1,D2): DivSchElt, DivSchElt → FldRatElt
SelfIntersection(D): DivSchElt → FldRatElt
Degree(D): DivSchElt → FldRatElt
Degree(D,H): DivSchElt, DivSchElt → FldRatElt
IsNef(D): DivSchElt → BoolElt
IsNefAndBig(D): DivSchElt → BoolElt
NegativePrimeDivisors(D): DivSchElt → SeqEnum
ZariskiDecomposition(D): DivSchElt → DivSchElt, DivSchElt
Reduction(D,p): DivSchElt, Any → DivSchElt
- Riemann-Roch Spaces
- Isolated Points on Schemes
- Advanced Examples