OAI/AlgebraicGeometry/StableCoordinate/DeterminantDomain.lean

GitHub source file

10 declarations, 0 contain sorry, 0 declared as axioms

Domain properties of the two concrete auxiliary rings

The determinant equation and the quadric relation are irreducible primitive linear polynomials in one of their variables. This file proves their principal ideals prime, and hence the corresponding affine coordinate rings are domains, over every unique factorization domain.

  1. def OAI.StableCoordinate.DeterminantDomain.determinantRelation line 21

    Source documentation

    Variables are ordered a,d,b,c,u.

    def determinantRelation : MvPolynomial (Fin 5) k :=
    …
  2. def OAI.StableCoordinate.DeterminantDomain.quadricRelation line 25

    Source documentation

    Variables are ordered x,y,z,u.

    def quadricRelation : MvPolynomial (Fin 4) k :=
    …
  3. theorem OAI.StableCoordinate.DeterminantDomain.determinantRelation_irreducible line 29
  4. theorem OAI.StableCoordinate.DeterminantDomain.quadricRelation_irreducible line 52
  5. theorem OAI.StableCoordinate.DeterminantDomain.determinantIdeal_isPrime line 77

    Source documentation

    The actual determinant hypersurface ideal is prime.

    theorem determinantIdeal_isPrime :
        (Ideal.span {determinantRelation k}).IsPrime :=
    …

    Mentions: OAI.StableCoordinate.DeterminantDomain.determinantRelation

  6. theorem OAI.StableCoordinate.DeterminantDomain.quadricIdeal_isPrime line 82

    Source documentation

    The actual quadric hypersurface ideal is prime.

    theorem quadricIdeal_isPrime :
        (Ideal.span {quadricRelation k}).IsPrime :=
    …

    Mentions: OAI.StableCoordinate.DeterminantDomain.quadricRelation

  7. abbrev OAI.StableCoordinate.DeterminantDomain.DeterminantRing line 87

    Source documentation

    Coordinate ring of the determinant hypersurface, ordered a,d,b,c,u.

    abbrev DeterminantRing :=
    …
  8. abbrev OAI.StableCoordinate.DeterminantDomain.QuadricRing line 91

    Source documentation

    Coordinate ring of the quadric times the u-line, ordered x,y,z,u.

    abbrev QuadricRing :=
    …
  9. instance OAI.StableCoordinate.DeterminantDomain.determinantRing_isDomain line 94
  10. instance OAI.StableCoordinate.DeterminantDomain.quadricRing_isDomain line 97