The gcd height of a function and its complement #
Control the common divisor of a function and one minus that function using local orders, exceptional places, and outside height.
@[instance_reducible]
noncomputable def
BGS.CorvajaZannier.oneSubGcdPolynomialAlgebra
(K : Type u_1)
[Field K]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
:
Algebra (Polynomial K) L
The algebra structure from K[X] to L used in the finite extension one sub gcd height
construction.
Equations
- BGS.CorvajaZannier.oneSubGcdPolynomialAlgebra K L = ((algebraMap (RatFunc K) L).comp (algebraMap (Polynomial K) (RatFunc K))).toAlgebra
Instances For
theorem
BGS.CorvajaZannier.oneSubGcdPolynomialScalarTower
(K : Type u_1)
[Field K]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
:
IsScalarTower (Polynomial K) (RatFunc K) L
theorem
BGS.CorvajaZannier.oneSubGcdFiniteIntegralClosureModuleFinite
(K : Type u_1)
[Field K]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
:
Module.Finite (Polynomial K) ↥(RatFuncFiniteIntegralClosure K L)
theorem
BGS.CorvajaZannier.oneSubGcdPolynomialTorsionFreeTop
(K : Type u_1)
[Field K]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
:
theorem
BGS.CorvajaZannier.oneSubGcdFiniteIntegralClosureIsTorsionFree
(K : Type u_1)
[Field K]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
:
theorem
BGS.CorvajaZannier.oneSubGcdInfinityIntegralClosureModuleFinite
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
:
theorem
BGS.CorvajaZannier.oneSubGcdInfinityIntegralClosureIsIntegral
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
:
theorem
BGS.CorvajaZannier.oneSubGcdInfinityTorsionFreeTop
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
:
theorem
BGS.CorvajaZannier.oneSubGcdInfinityIntegralClosureIsTorsionFree
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
:
theorem
BGS.CorvajaZannier.oneSubGcdInfinityIntegralClosureIsDedekindDomain
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
:
theorem
BGS.CorvajaZannier.finiteExtensionPrincipalDivisor_add_ge_min
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
(x y : L)
(hx : x ≠ 0)
(hy : y ≠ 0)
(hxy : x + y ≠ 0)
(w : FiniteExtensionPlace K L)
:
min ((finiteExtensionPrincipalDivisor K L x) w) ((finiteExtensionPrincipalDivisor K L y) w) ≤ (finiteExtensionPrincipalDivisor K L (x + y)) w
theorem
BGS.CorvajaZannier.finiteExtensionPrincipalDivisor_neg_apply
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
(x : L)
(hx : x ≠ 0)
(w : FiniteExtensionPlace K L)
:
theorem
BGS.CorvajaZannier.finiteExtensionPrincipalDivisor_one_sub_nonnegative_of_eq_zero
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
(x : L)
(hxone : x ≠ 1)
(w : FiniteExtensionPlace K L)
(hzero : (finiteExtensionPrincipalDivisor K L x) w = 0)
:
theorem
BGS.CorvajaZannier.finiteExtensionPrincipalDivisor_eq_zero_of_one_sub_pos
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
(x : L)
(hx : x ≠ 0)
(hxone : x ≠ 1)
(w : FiniteExtensionPlace K L)
(hpos : 0 < (finiteExtensionPrincipalDivisor K L (1 - x)) w)
:
noncomputable def
BGS.CorvajaZannier.propositionTwoExceptionalPlaces
(K : Type u_1)
[Field K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
(u v : L)
:
Finset (FiniteExtensionPlace K L)
The exceptional places used in Proposition 2: exactly the zeroes and poles of the two coordinates.
Equations
- One or more equations did not get rendered due to their size.
Instances For
theorem
BGS.CorvajaZannier.finiteExtensionOneSubGcd_add_outsideHeight_le_positiveDegree
(K : Type u_1)
[Field K]
[DecidableEq K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
(u v : L)
(hu : u ≠ 0)
(hv : v ≠ 0)
(huone : u ≠ 1)
(hvone : v ≠ 1)
:
finiteExtensionGcdWeightedDegree K L (1 - u) (1 - v) + finiteExtensionOutsideHeight K L ((1 - u) / (1 - v)) (propositionTwoExceptionalPlaces K L u v) ≤ finiteExtensionPositiveDegree K L (1 - v)
The divisor-theoretic gcd comparison used in Proposition 2, now on the actual exhaustive place type used by the canonical Wronskian sum.
theorem
BGS.CorvajaZannier.finiteExtensionOneSubGcd_add_outsideHeight_le_positiveDegree_coordinate
(K : Type u_1)
[Field K]
[DecidableEq K]
[DecidableEq (RatFunc K)]
(L : Type u_2)
[Field L]
[Algebra (RatFunc K) L]
[FiniteDimensional (RatFunc K) L]
[Algebra.IsSeparable (RatFunc K) L]
(u v : L)
(hu : u ≠ 0)
(hv : v ≠ 0)
(huone : u ≠ 1)
(hvone : v ≠ 1)
:
finiteExtensionGcdWeightedDegree K L (1 - u) (1 - v) + finiteExtensionOutsideHeight K L ((1 - u) / (1 - v)) (propositionTwoExceptionalPlaces K L u v) ≤ finiteExtensionPositiveDegree K L v
In the gcd comparison, the positive degree of 1-v is exactly the
coordinate height, hence the positive degree of v.