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lmul' : S ⊗[R] S →ₐ[R] S
alg_hom_of_linear_map_tensor_product (linear_map.mul' R S) (λ a₁ a₂ b₁ b₂, by simp only [linear_map.mul'_apply, mul_mul_mul_comm]) (λ r, by simp only [linear_map.mul'_apply, _root_.mul_one])
def
algebra.tensor_product.lmul'
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "linear_map.mul'", "linear_map.mul'_apply", "mul_mul_mul_comm" ]
`linear_map.mul'` is an alg_hom on commutative rings.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
lmul'_to_linear_map : (lmul' R : _ →ₐ[R] S).to_linear_map = linear_map.mul' R S
rfl
lemma
algebra.tensor_product.lmul'_to_linear_map
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "linear_map.mul'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
lmul'_apply_tmul (a b : S) : lmul' R (a ⊗ₜ[R] b) = a * b
rfl
lemma
algebra.tensor_product.lmul'_apply_tmul
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
lmul'_comp_include_left : (lmul' R : _ →ₐ[R] S).comp include_left = alg_hom.id R S
alg_hom.ext $ _root_.mul_one
lemma
algebra.tensor_product.lmul'_comp_include_left
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "alg_hom.ext", "alg_hom.id" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
lmul'_comp_include_right : (lmul' R : _ →ₐ[R] S).comp include_right = alg_hom.id R S
alg_hom.ext $ _root_.one_mul
lemma
algebra.tensor_product.lmul'_comp_include_right
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "alg_hom.ext", "alg_hom.id" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_map : A ⊗[R] B →ₐ[R] S
(lmul' R).comp (tensor_product.map f g)
def
algebra.tensor_product.product_map
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "tensor_product.map" ]
If `S` is commutative, for a pair of morphisms `f : A →ₐ[R] S`, `g : B →ₐ[R] S`, We obtain a map `A ⊗[R] B →ₐ[R] S` that commutes with `f`, `g` via `a ⊗ b ↦ f(a) * g(b)`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_map_apply_tmul (a : A) (b : B) : product_map f g (a ⊗ₜ b) = f a * g b
by { unfold product_map lmul', simp }
lemma
algebra.tensor_product.product_map_apply_tmul
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_map_left_apply (a : A) : product_map f g ((include_left : A →ₐ[R] A ⊗ B) a) = f a
by simp
lemma
algebra.tensor_product.product_map_left_apply
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_map_left : (product_map f g).comp include_left = f
alg_hom.ext $ by simp
lemma
algebra.tensor_product.product_map_left
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "alg_hom.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_map_right_apply (b : B) : product_map f g (include_right b) = g b
by simp
lemma
algebra.tensor_product.product_map_right_apply
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_map_right : (product_map f g).comp include_right = g
alg_hom.ext $ by simp
lemma
algebra.tensor_product.product_map_right
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "alg_hom.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_map_range : (product_map f g).range = f.range ⊔ g.range
by rw [product_map, alg_hom.range_comp, map_range, map_sup, ←alg_hom.range_comp, ←alg_hom.range_comp, ←alg_hom.comp_assoc, ←alg_hom.comp_assoc, lmul'_comp_include_left, lmul'_comp_include_right, alg_hom.id_comp, alg_hom.id_comp]
lemma
algebra.tensor_product.product_map_range
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "alg_hom.id_comp", "alg_hom.range_comp" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_left_alg_hom (f : A' →ₐ[A] S) (g : B →ₐ[R] S) : A' ⊗[R] B →ₐ[A] S
{ commutes' := λ r, by { dsimp, simp }, ..(product_map (f.restrict_scalars R) g).to_ring_hom }
def
algebra.tensor_product.product_left_alg_hom
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[]
If `A`, `B` are `R`-algebras, `A'` is an `A`-algebra, then the product map of `f : A' →ₐ[A] S` and `g : B →ₐ[R] S` is an `A`-algebra homomorphism.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
basis_aux : R ⊗[k] M ≃ₗ[k] (ι →₀ R)
(_root_.tensor_product.congr (finsupp.linear_equiv.finsupp_unique k R punit).symm b.repr) ≪≫ₗ (finsupp_tensor_finsupp k R k punit ι).trans (finsupp.lcongr (equiv.unique_prod ι punit) (_root_.tensor_product.rid k R))
def
algebra.tensor_product.basis_aux
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "equiv.unique_prod", "finsupp.lcongr", "finsupp.linear_equiv.finsupp_unique", "finsupp_tensor_finsupp" ]
Given a `k`-algebra `R` and a `k`-basis of `M,` this is a `k`-linear isomorphism `R ⊗[k] M ≃ (ι →₀ R)` (which is in fact `R`-linear).
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
basis_aux_tmul (r : R) (m : M) : basis_aux R b (r ⊗ₜ m) = r • (finsupp.map_range (algebra_map k R) (map_zero _) (b.repr m))
begin ext, simp [basis_aux, ←algebra.commutes, algebra.smul_def], end
lemma
algebra.tensor_product.basis_aux_tmul
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "algebra.smul_def", "algebra_map", "finsupp.map_range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
basis_aux_map_smul (r : R) (x : R ⊗[k] M) : basis_aux R b (r • x) = r • basis_aux R b x
tensor_product.induction_on x (by simp) (λ x y, by simp only [tensor_product.smul_tmul', basis_aux_tmul, smul_assoc]) (λ x y hx hy, by simp [hx, hy])
lemma
algebra.tensor_product.basis_aux_map_smul
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "smul_assoc", "tensor_product.induction_on", "tensor_product.smul_tmul'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
basis : basis ι R (R ⊗[k] M)
{ repr := { map_smul' := basis_aux_map_smul b, .. basis_aux R b } }
def
algebra.tensor_product.basis
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "basis" ]
Given a `k`-algebra `R`, this is the `R`-basis of `R ⊗[k] M` induced by a `k`-basis of `M`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
basis_repr_tmul (r : R) (m : M) : (basis R b).repr (r ⊗ₜ m) = r • (finsupp.map_range (algebra_map k R) (map_zero _) (b.repr m))
basis_aux_tmul _ _ _
lemma
algebra.tensor_product.basis_repr_tmul
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "algebra_map", "basis", "finsupp.map_range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
basis_repr_symm_apply (r : R) (i : ι) : (basis R b).repr.symm (finsupp.single i r) = r ⊗ₜ b.repr.symm (finsupp.single i 1)
by simp [basis, equiv.unique_prod_symm_apply, basis_aux]
lemma
algebra.tensor_product.basis_repr_symm_apply
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "basis", "equiv.unique_prod_symm_apply", "finsupp.single" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
End_tensor_End_alg_hom : (End R M) ⊗[R] (End R N) →ₐ[R] End R (M ⊗[R] N)
begin refine algebra.tensor_product.alg_hom_of_linear_map_tensor_product (hom_tensor_hom_map R M N M N) _ _, { intros f₁ f₂ g₁ g₂, simp only [hom_tensor_hom_map_apply, tensor_product.map_mul] }, { intro r, simp only [hom_tensor_hom_map_apply], ext m n, simp [smul_tmul] } end
def
module.End_tensor_End_alg_hom
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "algebra.tensor_product.alg_hom_of_linear_map_tensor_product", "tensor_product.map_mul" ]
The algebra homomorphism from `End M ⊗ End N` to `End (M ⊗ N)` sending `f ⊗ₜ g` to the `tensor_product.map f g`, the tensor product of the two maps.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
End_tensor_End_alg_hom_apply (f : End R M) (g : End R N) : End_tensor_End_alg_hom (f ⊗ₜ[R] g) = tensor_product.map f g
by simp only [End_tensor_End_alg_hom, algebra.tensor_product.alg_hom_of_linear_map_tensor_product_apply, hom_tensor_hom_map_apply]
lemma
module.End_tensor_End_alg_hom_apply
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "algebra.tensor_product.alg_hom_of_linear_map_tensor_product_apply", "tensor_product.map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
subalgebra.finite_dimensional_sup {K L : Type*} [field K] [comm_ring L] [algebra K L] (E1 E2 : subalgebra K L) [finite_dimensional K E1] [finite_dimensional K E2] : finite_dimensional K ↥(E1 ⊔ E2)
begin rw [←E1.range_val, ←E2.range_val, ←algebra.tensor_product.product_map_range], exact (algebra.tensor_product.product_map E1.val E2.val).to_linear_map.finite_dimensional_range, end
lemma
subalgebra.finite_dimensional_sup
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "algebra", "algebra.tensor_product.product_map", "comm_ring", "field", "finite_dimensional", "subalgebra" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
module_aux : A ⊗[R] B →ₗ[R] M →ₗ[R] M
tensor_product.lift { to_fun := λ a, a • (algebra.lsmul R M : B →ₐ[R] module.End R M).to_linear_map, map_add' := λ r t, by { ext, simp only [add_smul, linear_map.add_apply] }, map_smul' := λ n r, by { ext, simp only [ring_hom.id_apply, linear_map.smul_apply, smul_assoc] } }
def
tensor_product.algebra.module_aux
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "add_smul", "algebra.lsmul", "linear_map.add_apply", "linear_map.smul_apply", "module.End", "ring_hom.id_apply", "smul_assoc", "tensor_product.lift" ]
An auxiliary definition, used for constructing the `module (A ⊗[R] B) M` in `tensor_product.algebra.module` below.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
module_aux_apply (a : A) (b : B) (m : M) : module_aux (a ⊗ₜ[R] b) m = a • b • m
rfl
lemma
tensor_product.algebra.module_aux_apply
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
module : module (A ⊗[R] B) M
{ smul := λ x m, module_aux x m, zero_smul := λ m, by simp only [map_zero, linear_map.zero_apply], smul_zero := λ x, by simp only [map_zero], smul_add := λ x m₁ m₂, by simp only [map_add], add_smul := λ x y m, by simp only [map_add, linear_map.add_apply], one_smul := λ m, by simp only [module_aux_apply, algeb...
def
tensor_product.algebra.module
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[ "add_smul", "algebra.tensor_product.one_def", "algebra.tensor_product.tmul_mul_tmul", "linear_map.add_apply", "linear_map.mul_apply", "linear_map.zero_apply", "module", "mul_zero", "one_smul", "smul_add", "smul_zero", "tensor_product.induction_on", "zero_mul", "zero_smul" ]
If `M` is a representation of two different `R`-algebras `A` and `B` whose actions commute, then it is a representation the `R`-algebra `A ⊗[R] B`. An important example arises from a semiring `S`; allowing `S` to act on itself via left and right multiplication, the roles of `R`, `A`, `B`, `M` are played by `ℕ`, `S`, `...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_def (a : A) (b : B) (m : M) : (a ⊗ₜ[R] b) • m = a • b • m
rfl
lemma
tensor_product.algebra.smul_def
ring_theory
src/ring_theory/tensor_product.lean
[ "linear_algebra.finite_dimensional", "ring_theory.adjoin.basic", "linear_algebra.direct_sum.finsupp" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace : S →ₗ[R] R
(linear_map.trace R S).comp (lmul R S).to_linear_map
def
algebra.trace
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "linear_map.trace" ]
The trace of an element `s` of an `R`-algebra is the trace of `(*) s`, as an `R`-linear map.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_apply (x) : trace R S x = linear_map.trace R S (lmul R S x)
rfl
lemma
algebra.trace_apply
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "linear_map.trace" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_eq_zero_of_not_exists_basis (h : ¬ ∃ (s : finset S), nonempty (basis s R S)) : trace R S = 0
by { ext s, simp [trace_apply, linear_map.trace, h] }
lemma
algebra.trace_eq_zero_of_not_exists_basis
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "basis", "finset", "linear_map.trace" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_eq_matrix_trace [decidable_eq ι] (b : basis ι R S) (s : S) : trace R S s = matrix.trace (algebra.left_mul_matrix b s)
by { rw [trace_apply, linear_map.trace_eq_matrix_trace _ b, ←to_matrix_lmul_eq], refl }
lemma
algebra.trace_eq_matrix_trace
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.left_mul_matrix", "basis", "linear_map.trace_eq_matrix_trace", "matrix.trace" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_algebra_map_of_basis (x : R) : trace R S (algebra_map R S x) = fintype.card ι • x
begin haveI := classical.dec_eq ι, rw [trace_apply, linear_map.trace_eq_matrix_trace R b, matrix.trace], convert finset.sum_const _, ext i, simp [-coe_lmul_eq_mul], end
lemma
algebra.trace_algebra_map_of_basis
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra_map", "classical.dec_eq", "fintype.card", "linear_map.trace_eq_matrix_trace", "matrix.trace" ]
If `x` is in the base field `K`, then the trace is `[L : K] * x`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_algebra_map (x : K) : trace K L (algebra_map K L x) = finrank K L • x
begin by_cases H : ∃ (s : finset L), nonempty (basis s K L), { rw [trace_algebra_map_of_basis H.some_spec.some, finrank_eq_card_basis H.some_spec.some] }, { simp [trace_eq_zero_of_not_exists_basis K H, finrank_eq_zero_of_not_exists_basis_finset H] } end
lemma
algebra.trace_algebra_map
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra_map", "basis", "finrank_eq_zero_of_not_exists_basis_finset", "finset" ]
If `x` is in the base field `K`, then the trace is `[L : K] * x`. (If `L` is not finite-dimensional over `K`, then `trace` and `finrank` return `0`.)
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_trace_of_basis [algebra S T] [is_scalar_tower R S T] {ι κ : Type*} [finite ι] [finite κ] (b : basis ι R S) (c : basis κ S T) (x : T) : trace R S (trace S T x) = trace R T x
begin haveI := classical.dec_eq ι, haveI := classical.dec_eq κ, casesI nonempty_fintype ι, casesI nonempty_fintype κ, rw [trace_eq_matrix_trace (b.smul c), trace_eq_matrix_trace b, trace_eq_matrix_trace c, matrix.trace, matrix.trace, matrix.trace, ← finset.univ_product_univ, finset.sum_product], ...
lemma
algebra.trace_trace_of_basis
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "alg_hom.map_sum", "algebra", "basis", "classical.dec_eq", "finite", "finset.univ_product_univ", "is_scalar_tower", "matrix.diag", "matrix.trace", "nonempty_fintype" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_comp_trace_of_basis [algebra S T] [is_scalar_tower R S T] {ι κ : Type*} [finite ι] [fintype κ] (b : basis ι R S) (c : basis κ S T) : (trace R S).comp ((trace S T).restrict_scalars R) = trace R T
by { ext, rw [linear_map.comp_apply, linear_map.restrict_scalars_apply, trace_trace_of_basis b c] }
lemma
algebra.trace_comp_trace_of_basis
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra", "basis", "finite", "fintype", "is_scalar_tower", "linear_map.comp_apply", "linear_map.restrict_scalars_apply", "restrict_scalars" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_trace [algebra K T] [algebra L T] [is_scalar_tower K L T] [finite_dimensional K L] [finite_dimensional L T] (x : T) : trace K L (trace L T x) = trace K T x
trace_trace_of_basis (basis.of_vector_space K L) (basis.of_vector_space L T) x
lemma
algebra.trace_trace
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra", "basis.of_vector_space", "finite_dimensional", "is_scalar_tower" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_comp_trace [algebra K T] [algebra L T] [is_scalar_tower K L T] [finite_dimensional K L] [finite_dimensional L T] : (trace K L).comp ((trace L T).restrict_scalars K) = trace K T
by { ext, rw [linear_map.comp_apply, linear_map.restrict_scalars_apply, trace_trace] }
lemma
algebra.trace_comp_trace
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra", "finite_dimensional", "is_scalar_tower", "linear_map.comp_apply", "linear_map.restrict_scalars_apply", "restrict_scalars" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_prod_apply [module.free R S] [module.free R T] [module.finite R S] [module.finite R T] (x : S × T) : trace R (S × T) x = trace R S x.fst + trace R T x.snd
begin nontriviality R, let f := (lmul R S).to_linear_map.prod_map (lmul R T).to_linear_map, have : (lmul R (S × T)).to_linear_map = (prod_map_linear R S T S T R).comp f := linear_map.ext₂ prod.mul_def, simp_rw [trace, this], exact trace_prod_map' _ _, end
lemma
algebra.trace_prod_apply
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "linear_map.ext₂", "module.finite", "module.free", "prod.mul_def" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_prod [module.free R S] [module.free R T] [module.finite R S] [module.finite R T] : trace R (S × T) = (trace R S).coprod (trace R T)
linear_map.ext $ λ p, by rw [coprod_apply, trace_prod_apply]
lemma
algebra.trace_prod
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "linear_map.ext", "module.finite", "module.free" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_form : bilin_form R S
(linear_map.compr₂ (lmul R S).to_linear_map (trace R S)).to_bilin
def
algebra.trace_form
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "bilin_form", "linear_map.compr₂" ]
The `trace_form` maps `x y : S` to the trace of `x * y`. It is a symmetric bilinear form and is nondegenerate if the extension is separable.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_form_apply (x y : S) : trace_form R S x y = trace R S (x * y)
rfl
lemma
algebra.trace_form_apply
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_form_is_symm : (trace_form R S).is_symm
λ x y, congr_arg (trace R S) (mul_comm _ _)
lemma
algebra.trace_form_is_symm
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "mul_comm" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_form_to_matrix [decidable_eq ι] (i j) : bilin_form.to_matrix b (trace_form R S) i j = trace R S (b i * b j)
by rw [bilin_form.to_matrix_apply, trace_form_apply]
lemma
algebra.trace_form_to_matrix
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "bilin_form.to_matrix", "bilin_form.to_matrix_apply" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_form_to_matrix_power_basis (h : power_basis R S) : bilin_form.to_matrix h.basis (trace_form R S) = of (λ i j, trace R S (h.gen ^ (↑i + ↑j : ℕ)))
by { ext, rw [trace_form_to_matrix, of_apply, pow_add, h.basis_eq_pow, h.basis_eq_pow] }
lemma
algebra.trace_form_to_matrix_power_basis
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "bilin_form.to_matrix", "pow_add", "power_basis" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
power_basis.trace_gen_eq_next_coeff_minpoly [nontrivial S] (pb : power_basis K S) : algebra.trace K S pb.gen = -(minpoly K pb.gen).next_coeff
begin have d_pos : 0 < pb.dim := power_basis.dim_pos pb, have d_pos' : 0 < (minpoly K pb.gen).nat_degree, { simpa }, haveI : nonempty (fin pb.dim) := ⟨⟨0, d_pos⟩⟩, rw [trace_eq_matrix_trace pb.basis, trace_eq_neg_charpoly_coeff, charpoly_left_mul_matrix, ← pb.nat_degree_minpoly, fintype.card_fin, ← next_c...
lemma
power_basis.trace_gen_eq_next_coeff_minpoly
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.trace", "charpoly_left_mul_matrix", "fintype.card_fin", "minpoly", "nontrivial", "power_basis", "power_basis.dim_pos" ]
Given `pb : power_basis K S`, the trace of `pb.gen` is `-(minpoly K pb.gen).next_coeff`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
power_basis.trace_gen_eq_sum_roots [nontrivial S] (pb : power_basis K S) (hf : (minpoly K pb.gen).splits (algebra_map K F)) : algebra_map K F (trace K S pb.gen) = ((minpoly K pb.gen).map (algebra_map K F)).roots.sum
begin rw [power_basis.trace_gen_eq_next_coeff_minpoly, ring_hom.map_neg, ← next_coeff_map (algebra_map K F).injective, sum_roots_eq_next_coeff_of_monic_of_split ((minpoly.monic (power_basis.is_integral_gen _)).map _) ((splits_id_iff_splits _).2 hf), neg_neg] end
lemma
power_basis.trace_gen_eq_sum_roots
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra_map", "minpoly", "minpoly.monic", "nontrivial", "power_basis", "power_basis.is_integral_gen", "power_basis.trace_gen_eq_next_coeff_minpoly", "ring_hom.map_neg" ]
Given `pb : power_basis K S`, then the trace of `pb.gen` is `((minpoly K pb.gen).map (algebra_map K F)).roots.sum`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_gen_eq_zero {x : L} (hx : ¬ is_integral K x) : algebra.trace K K⟮x⟯ (adjoin_simple.gen K x) = 0
begin rw [trace_eq_zero_of_not_exists_basis, linear_map.zero_apply], contrapose! hx, obtain ⟨s, ⟨b⟩⟩ := hx, refine is_integral_of_mem_of_fg (K⟮x⟯).to_subalgebra _ x _, { exact (submodule.fg_iff_finite_dimensional _).mpr (finite_dimensional.of_fintype_basis b) }, { exact subset_adjoin K _ (set.mem_singleton ...
lemma
intermediate_field.adjoin_simple.trace_gen_eq_zero
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.trace", "finite_dimensional.of_fintype_basis", "is_integral", "is_integral_of_mem_of_fg", "linear_map.zero_apply", "set.mem_singleton", "submodule.fg_iff_finite_dimensional" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_gen_eq_sum_roots (x : L) (hf : (minpoly K x).splits (algebra_map K F)) : algebra_map K F (trace K K⟮x⟯ (adjoin_simple.gen K x)) = ((minpoly K x).map (algebra_map K F)).roots.sum
begin have injKxL := (algebra_map K⟮x⟯ L).injective, by_cases hx : is_integral K x, swap, { simp [minpoly.eq_zero hx, trace_gen_eq_zero hx], }, have hx' : is_integral K (adjoin_simple.gen K x), { rwa [← is_integral_algebra_map_iff injKxL, adjoin_simple.algebra_map_gen], apply_instance }, rw [← adjoin.po...
lemma
intermediate_field.adjoin_simple.trace_gen_eq_sum_roots
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra_map", "is_integral", "is_integral_algebra_map_iff", "minpoly", "minpoly.eq_of_algebra_map_eq", "minpoly.eq_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_eq_trace_adjoin [finite_dimensional K L] (x : L) : algebra.trace K L x = finrank K⟮x⟯ L • trace K K⟮x⟯ (adjoin_simple.gen K x)
begin rw ← @trace_trace _ _ K K⟮x⟯ _ _ _ _ _ _ _ _ x, conv in x { rw ← intermediate_field.adjoin_simple.algebra_map_gen K x }, rw [trace_algebra_map, linear_map.map_smul_of_tower], end
lemma
trace_eq_trace_adjoin
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.trace", "finite_dimensional", "intermediate_field.adjoin_simple.algebra_map_gen", "linear_map.map_smul_of_tower" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_eq_sum_roots [finite_dimensional K L] {x : L} (hF : (minpoly K x).splits (algebra_map K F)) : algebra_map K F (algebra.trace K L x) = finrank K⟮x⟯ L • ((minpoly K x).map (algebra_map K _)).roots.sum
by rw [trace_eq_trace_adjoin K x, algebra.smul_def, ring_hom.map_mul, ← algebra.smul_def, intermediate_field.adjoin_simple.trace_gen_eq_sum_roots _ hF, is_scalar_tower.algebra_map_smul]
lemma
trace_eq_sum_roots
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.smul_def", "algebra.trace", "algebra_map", "finite_dimensional", "intermediate_field.adjoin_simple.trace_gen_eq_sum_roots", "is_scalar_tower.algebra_map_smul", "minpoly", "ring_hom.map_mul", "trace_eq_trace_adjoin" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
algebra.is_integral_trace [finite_dimensional L F] {x : F} (hx : is_integral R x) : is_integral R (algebra.trace L F x)
begin have hx' : is_integral L x := is_integral_of_is_scalar_tower hx, rw [← is_integral_algebra_map_iff (algebra_map L (algebraic_closure F)).injective, trace_eq_sum_roots], { refine (is_integral.multiset_sum _).nsmul _, intros y hy, rw mem_roots_map (minpoly.ne_zero hx') at hy, use [minpoly R ...
lemma
algebra.is_integral_trace
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.trace", "algebra_map", "algebraic_closure", "finite_dimensional", "is_alg_closed.splits_codomain", "is_integral", "is_integral.multiset_sum", "is_integral_algebra_map_iff", "is_integral_of_is_scalar_tower", "minpoly", "minpoly.aeval_of_is_scalar_tower", "minpoly.monic", "minpoly.ne_...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_eq_sum_embeddings_gen (pb : power_basis K L) (hE : (minpoly K pb.gen).splits (algebra_map K E)) (hfx : (minpoly K pb.gen).separable) : algebra_map K E (algebra.trace K L pb.gen) = (@@finset.univ (power_basis.alg_hom.fintype pb)).sum (λ σ, σ pb.gen)
begin letI := classical.dec_eq E, rw [pb.trace_gen_eq_sum_roots hE, fintype.sum_equiv pb.lift_equiv', finset.sum_mem_multiset, finset.sum_eq_multiset_sum, multiset.to_finset_val, multiset.dedup_eq_self.mpr _, multiset.map_id], { exact nodup_roots ((separable_map _).mpr hfx) }, { intro x, refl }, {...
lemma
trace_eq_sum_embeddings_gen
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.trace", "algebra_map", "classical.dec_eq", "finset.univ", "minpoly", "multiset.map_id", "multiset.to_finset_val", "power_basis", "power_basis.alg_hom.fintype" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum_embeddings_eq_finrank_mul [finite_dimensional K F] [is_separable K F] (pb : power_basis K L) : ∑ σ : F →ₐ[K] E, σ (algebra_map L F pb.gen) = finrank L F • (@@finset.univ (power_basis.alg_hom.fintype pb)).sum (λ σ : L →ₐ[K] E, σ pb.gen)
begin haveI : finite_dimensional L F := finite_dimensional.right K L F, haveI : is_separable L F := is_separable_tower_top_of_is_separable K L F, letI : fintype (L →ₐ[K] E) := power_basis.alg_hom.fintype pb, letI : ∀ (f : L →ₐ[K] E), fintype (@@alg_hom L F E _ _ _ _ f.to_ring_hom.to_algebra) := _, -- will b...
lemma
sum_embeddings_eq_finrank_mul
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "alg_hom", "alg_hom.card", "alg_hom.comp_apply", "alg_hom.restrict_domain", "alg_hom_equiv_sigma", "algebra", "algebra_map", "equiv.coe_fn_mk", "finite_dimensional", "finite_dimensional.right", "finset.card_univ", "finset.univ", "finset.univ_sigma_univ", "fintype", "is_scalar_tower.coe_t...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_eq_sum_embeddings [finite_dimensional K L] [is_separable K L] {x : L} : algebra_map K E (algebra.trace K L x) = ∑ σ : L →ₐ[K] E, σ x
begin have hx := is_separable.is_integral K x, rw [trace_eq_trace_adjoin K x, algebra.smul_def, ring_hom.map_mul, ← adjoin.power_basis_gen hx, trace_eq_sum_embeddings_gen E (adjoin.power_basis hx) (is_alg_closed.splits_codomain _), ← algebra.smul_def, algebra_map_smul], { exact (sum_embeddings_eq_finr...
lemma
trace_eq_sum_embeddings
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.smul_def", "algebra.trace", "algebra_map", "algebra_map_smul", "finite_dimensional", "is_alg_closed.splits_codomain", "is_separable", "is_separable.is_integral", "is_separable.separable", "is_separable_tower_bot_of_is_separable", "ring_hom.map_mul", "sum_embeddings_eq_finrank_mul", ...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_eq_sum_automorphisms (x : L) [finite_dimensional K L] [is_galois K L] : algebra_map K L (algebra.trace K L x) = ∑ (σ : L ≃ₐ[K] L), σ x
begin apply no_zero_smul_divisors.algebra_map_injective L (algebraic_closure L), rw map_sum (algebra_map L (algebraic_closure L)), rw ← fintype.sum_equiv (normal.alg_hom_equiv_aut K (algebraic_closure L) L), { rw ←trace_eq_sum_embeddings (algebraic_closure L), { simp only [algebra_map_eq_smul_one, smul_one_...
lemma
trace_eq_sum_automorphisms
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "alg_equiv.coe_of_bijective", "alg_hom.restrict_normal'", "alg_hom.restrict_normal_commutes", "algebra.trace", "algebra_map", "algebraic_closure", "equiv.coe_fn_mk", "finite_dimensional", "is_galois", "no_zero_smul_divisors.algebra_map_injective", "normal.alg_hom_equiv_aut", "ring_hom.id_apply...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix (b : κ → B) : matrix κ κ A
of $ λ i j, trace_form A B (b i) (b j)
def
algebra.trace_matrix
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "matrix" ]
Given an `A`-algebra `B` and `b`, an `κ`-indexed family of elements of `B`, we define `trace_matrix A b` as the matrix whose `(i j)`-th element is the trace of `b i * b j`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix_apply (b : κ → B) (i j) : trace_matrix A b i j = trace_form A B (b i) (b j)
rfl
lemma
algebra.trace_matrix_apply
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix_reindex {κ' : Type*} (b : basis κ A B) (f : κ ≃ κ') : trace_matrix A (b.reindex f) = reindex f f (trace_matrix A b)
by {ext x y, simp}
lemma
algebra.trace_matrix_reindex
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "basis", "reindex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix_of_matrix_vec_mul [fintype κ] (b : κ → B) (P : matrix κ κ A) : trace_matrix A ((P.map (algebra_map A B)).vec_mul b) = Pᵀ ⬝ (trace_matrix A b) ⬝ P
begin ext α β, rw [trace_matrix_apply, vec_mul, dot_product, vec_mul, dot_product, matrix.mul_apply, bilin_form.sum_left, fintype.sum_congr _ _ (λ (i : κ), @bilin_form.sum_right _ _ _ _ _ _ _ _ (b i * P.map (algebra_map A B) i α) (λ (y : κ), b y * P.map (algebra_map A B) y β)), sum_comm], congr, ext x, ...
lemma
algebra.trace_matrix_of_matrix_vec_mul
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra.smul_mul_assoc", "algebra_map", "bilin_form.sum_left", "bilin_form.sum_right", "fintype", "linear_map.map_smulₛₗ", "matrix", "matrix.mul_apply", "mul_comm", "ring_hom.id_apply" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix_of_matrix_mul_vec [fintype κ] (b : κ → B) (P : matrix κ κ A) : trace_matrix A ((P.map (algebra_map A B)).mul_vec b) = P ⬝ (trace_matrix A b) ⬝ Pᵀ
begin refine add_equiv.injective (transpose_add_equiv _ _ _) _, rw [transpose_add_equiv_apply, transpose_add_equiv_apply, ← vec_mul_transpose, ← transpose_map, trace_matrix_of_matrix_vec_mul, transpose_transpose, transpose_mul, transpose_transpose, transpose_mul] end
lemma
algebra.trace_matrix_of_matrix_mul_vec
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra_map", "fintype", "matrix" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix_of_basis [fintype κ] [decidable_eq κ] (b : basis κ A B) : trace_matrix A b = bilin_form.to_matrix b (trace_form A B)
begin ext i j, rw [trace_matrix_apply, trace_form_apply, trace_form_to_matrix] end
lemma
algebra.trace_matrix_of_basis
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "basis", "bilin_form.to_matrix", "fintype" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix_of_basis_mul_vec (b : basis ι A B) (z : B) : (trace_matrix A b).mul_vec (b.equiv_fun z) = (λ i, trace A B (z * (b i)))
begin ext i, rw [← col_apply ((trace_matrix A b).mul_vec (b.equiv_fun z)) i unit.star, col_mul_vec, matrix.mul_apply, trace_matrix], simp only [col_apply, trace_form_apply], conv_lhs { congr, skip, funext, rw [mul_comm _ (b.equiv_fun z _), ← smul_eq_mul, of_apply, ← linear_map.map_smul] }, rw [← l...
lemma
algebra.trace_matrix_of_basis_mul_vec
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "basis", "finset.mul_sum", "linear_map.map_smul", "linear_map.map_sum", "matrix.mul_apply", "mul_comm", "mul_smul_comm", "smul_eq_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
embeddings_matrix (b : κ → B) : matrix κ (B →ₐ[A] C) C
of $ λ i (σ : B →ₐ[A] C), σ (b i)
def
algebra.embeddings_matrix
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "matrix" ]
`embeddings_matrix A C b : matrix κ (B →ₐ[A] C) C` is the matrix whose `(i, σ)` coefficient is `σ (b i)`. It is mostly useful for fields when `fintype.card κ = finrank A B` and `C` is algebraically closed.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
embeddings_matrix_apply (b : κ → B) (i) (σ : B →ₐ[A] C) : embeddings_matrix A C b i σ = σ (b i)
rfl
lemma
algebra.embeddings_matrix_apply
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
embeddings_matrix_reindex (b : κ → B) (e : κ ≃ (B →ₐ[A] C))
reindex (equiv.refl κ) e.symm (embeddings_matrix A C b)
def
algebra.embeddings_matrix_reindex
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "equiv.refl", "reindex" ]
`embeddings_matrix_reindex A C b e : matrix κ κ C` is the matrix whose `(i, j)` coefficient is `σⱼ (b i)`, where `σⱼ : B →ₐ[A] C` is the embedding corresponding to `j : κ` given by a bijection `e : κ ≃ (B →ₐ[A] C)`. It is mostly useful for fields and `C` is algebraically closed. In this case, in presence of `h : ...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
embeddings_matrix_reindex_eq_vandermonde (pb : power_basis A B) (e : fin pb.dim ≃ (B →ₐ[A] C)) : embeddings_matrix_reindex A C pb.basis e = (vandermonde (λ i, e i pb.gen))ᵀ
by { ext i j, simp [embeddings_matrix_reindex, embeddings_matrix] }
lemma
algebra.embeddings_matrix_reindex_eq_vandermonde
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "power_basis" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix_eq_embeddings_matrix_mul_trans : (trace_matrix K b).map (algebra_map K E) = (embeddings_matrix K E b) ⬝ (embeddings_matrix K E b)ᵀ
by { ext i j, simp [trace_eq_sum_embeddings, embeddings_matrix, matrix.mul_apply] }
lemma
algebra.trace_matrix_eq_embeddings_matrix_mul_trans
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra_map", "matrix.mul_apply", "trace_eq_sum_embeddings" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_matrix_eq_embeddings_matrix_reindex_mul_trans [fintype κ] (e : κ ≃ (L →ₐ[K] E)) : (trace_matrix K b).map (algebra_map K E) = (embeddings_matrix_reindex K E b e) ⬝ (embeddings_matrix_reindex K E b e)ᵀ
by rw [trace_matrix_eq_embeddings_matrix_mul_trans, embeddings_matrix_reindex, reindex_apply, transpose_submatrix, ← submatrix_mul_transpose_submatrix, ← equiv.coe_refl, equiv.refl_symm]
lemma
algebra.trace_matrix_eq_embeddings_matrix_reindex_mul_trans
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "algebra_map", "equiv.coe_refl", "equiv.refl_symm", "fintype", "reindex_apply" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
det_trace_matrix_ne_zero' [is_separable K L] : det (trace_matrix K pb.basis) ≠ 0
begin suffices : algebra_map K (algebraic_closure L) (det (trace_matrix K pb.basis)) ≠ 0, { refine mt (λ ht, _) this, rw [ht, ring_hom.map_zero] }, haveI : finite_dimensional K L := pb.finite_dimensional, let e : fin pb.dim ≃ (L →ₐ[K] algebraic_closure L) := (fintype.equiv_fin_of_card_eq _).symm, rw [ring...
lemma
det_trace_matrix_ne_zero'
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "alg_hom.card", "algebra_map", "algebraic_closure", "finite_dimensional", "finset.prod_eq_zero_iff", "fintype.equiv_fin_of_card_eq", "is_separable", "not_exists", "ring_hom.map_det", "ring_hom.map_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
det_trace_form_ne_zero [is_separable K L] [decidable_eq ι] (b : basis ι K L) : det (bilin_form.to_matrix b (trace_form K L)) ≠ 0
begin haveI : finite_dimensional K L := finite_dimensional.of_fintype_basis b, let pb : power_basis K L := field.power_basis_of_finite_of_separable _ _, rw [← bilin_form.to_matrix_mul_basis_to_matrix pb.basis b, ← det_comm' (pb.basis.to_matrix_mul_to_matrix_flip b) _, ← matrix.mul_assoc, det_mul], s...
lemma
det_trace_form_ne_zero
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "basis", "basis.to_matrix_mul_to_matrix_flip", "bilin_form.to_matrix", "bilin_form.to_matrix_mul_basis_to_matrix", "det_trace_matrix_ne_zero'", "field.power_basis_of_finite_of_separable", "finite_dimensional", "finite_dimensional.of_fintype_basis", "is_separable", "is_unit_of_mul_eq_one", "matri...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trace_form_nondegenerate [finite_dimensional K L] [is_separable K L] : (trace_form K L).nondegenerate
bilin_form.nondegenerate_of_det_ne_zero (trace_form K L) _ (det_trace_form_ne_zero (finite_dimensional.fin_basis K L))
theorem
trace_form_nondegenerate
ring_theory
src/ring_theory/trace.lean
[ "linear_algebra.matrix.bilinear_form", "linear_algebra.matrix.charpoly.minpoly", "linear_algebra.determinant", "linear_algebra.finite_dimensional", "linear_algebra.vandermonde", "linear_algebra.trace", "field_theory.is_alg_closed.algebraic_closure", "field_theory.primitive_element", "field_theory.ga...
[ "bilin_form.nondegenerate_of_det_ne_zero", "det_trace_form_ne_zero", "finite_dimensional", "finite_dimensional.fin_basis", "is_separable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
wf_dvd_monoid (α : Type*) [comm_monoid_with_zero α] : Prop
(well_founded_dvd_not_unit : well_founded (@dvd_not_unit α _))
class
wf_dvd_monoid
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "comm_monoid_with_zero", "dvd_not_unit" ]
Well-foundedness of the strict version of |, which is equivalent to the descending chain condition on divisibility and to the ascending chain condition on principal ideals in an integral domain.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_noetherian_ring.wf_dvd_monoid [comm_ring α] [is_domain α] [is_noetherian_ring α] : wf_dvd_monoid α
⟨by { convert inv_image.wf (λ a, ideal.span ({a} : set α)) (well_founded_submodule_gt _ _), ext, exact ideal.span_singleton_lt_span_singleton.symm }⟩
instance
is_noetherian_ring.wf_dvd_monoid
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "comm_ring", "ideal.span", "is_domain", "is_noetherian_ring", "well_founded_submodule_gt", "wf_dvd_monoid" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
of_wf_dvd_monoid_associates (h : wf_dvd_monoid (associates α)): wf_dvd_monoid α
⟨begin haveI := h, refine (surjective.well_founded_iff mk_surjective _).2 well_founded_dvd_not_unit, intros, rw mk_dvd_not_unit_mk_iff end⟩
theorem
wf_dvd_monoid.of_wf_dvd_monoid_associates
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associates", "surjective.well_founded_iff", "wf_dvd_monoid" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
wf_dvd_monoid_associates : wf_dvd_monoid (associates α)
⟨begin refine (surjective.well_founded_iff mk_surjective _).1 well_founded_dvd_not_unit, intros, rw mk_dvd_not_unit_mk_iff end⟩
instance
wf_dvd_monoid.wf_dvd_monoid_associates
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associates", "surjective.well_founded_iff", "wf_dvd_monoid" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
well_founded_associates : well_founded ((<) : associates α → associates α → Prop)
subrelation.wf (λ x y, dvd_not_unit_of_lt) well_founded_dvd_not_unit
theorem
wf_dvd_monoid.well_founded_associates
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associates" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exists_irreducible_factor {a : α} (ha : ¬ is_unit a) (ha0 : a ≠ 0) : ∃ i, irreducible i ∧ i ∣ a
let ⟨b, hs, hr⟩ := well_founded_dvd_not_unit.has_min {b | b ∣ a ∧ ¬ is_unit b} ⟨a, dvd_rfl, ha⟩ in ⟨b, ⟨hs.2, λ c d he, let h := dvd_trans ⟨d, he⟩ hs.1 in or_iff_not_imp_left.2 $ λ hc, of_not_not $ λ hd, hr c ⟨h, hc⟩ ⟨ne_zero_of_dvd_ne_zero ha0 h, d, hd, he⟩⟩, hs.1⟩
lemma
wf_dvd_monoid.exists_irreducible_factor
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "dvd_rfl", "dvd_trans", "irreducible", "is_unit", "of_not_not" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
induction_on_irreducible {P : α → Prop} (a : α) (h0 : P 0) (hu : ∀ u : α, is_unit u → P u) (hi : ∀ a i : α, a ≠ 0 → irreducible i → P a → P (i * a)) : P a
by haveI := classical.dec; exact well_founded_dvd_not_unit.fix (λ a ih, if ha0 : a = 0 then ha0.substr h0 else if hau : is_unit a then hu a hau else let ⟨i, hii, b, hb⟩ := exists_irreducible_factor hau ha0, hb0 : b ≠ 0 := ne_zero_of_dvd_ne_zero ha0 ⟨i, mul_comm i b ▸ hb⟩ in hb.symm ▸ hi b i hb0 hi...
lemma
wf_dvd_monoid.induction_on_irreducible
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "classical.dec", "ih", "irreducible", "is_unit", "mul_comm", "ne_zero_of_dvd_ne_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exists_factors (a : α) : a ≠ 0 → ∃ f : multiset α, (∀ b ∈ f, irreducible b) ∧ associated f.prod a
induction_on_irreducible a (λ h, (h rfl).elim) (λ u hu _, ⟨0, λ _ h, h.elim, hu.unit, one_mul _⟩) (λ a i ha0 hi ih _, let ⟨s, hs⟩ := ih ha0 in ⟨i ::ₘ s, λ b H, (multiset.mem_cons.1 H).elim (λ h, h.symm ▸ hi) (hs.1 b), by { rw s.prod_cons i, exact hs.2.mul_left i }⟩)
lemma
wf_dvd_monoid.exists_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated", "ih", "irreducible", "multiset", "one_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
not_unit_iff_exists_factors_eq (a : α) (hn0 : a ≠ 0) : ¬ is_unit a ↔ ∃ f : multiset α, (∀ b ∈ f, irreducible b) ∧ f.prod = a ∧ f ≠ ∅
⟨λ hnu, begin obtain ⟨f, hi, u, rfl⟩ := exists_factors a hn0, obtain ⟨b, h⟩ := multiset.exists_mem_of_ne_zero (λ h : f = 0, hnu $ by simp [h]), classical, refine ⟨(f.erase b).cons (b * u), λ a ha, _, _, multiset.cons_ne_zero⟩, { obtain (rfl|ha) := multiset.mem_cons.1 ha, exacts [associated.irreducible ⟨u,rf...
lemma
wf_dvd_monoid.not_unit_iff_exists_factors_eq
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated.irreducible", "irreducible", "is_unit", "mul_assoc", "mul_comm", "multiset", "multiset.dvd_prod", "multiset.exists_mem_of_ne_zero", "multiset.mem_of_mem_erase", "multiset.prod_cons", "multiset.prod_erase", "not_is_unit_of_not_is_unit_dvd" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
wf_dvd_monoid.of_well_founded_associates [cancel_comm_monoid_with_zero α] (h : well_founded ((<) : associates α → associates α → Prop)) : wf_dvd_monoid α
wf_dvd_monoid.of_wf_dvd_monoid_associates ⟨by { convert h, ext, exact associates.dvd_not_unit_iff_lt }⟩
theorem
wf_dvd_monoid.of_well_founded_associates
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associates", "associates.dvd_not_unit_iff_lt", "cancel_comm_monoid_with_zero", "wf_dvd_monoid", "wf_dvd_monoid.of_wf_dvd_monoid_associates" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
wf_dvd_monoid.iff_well_founded_associates [cancel_comm_monoid_with_zero α] : wf_dvd_monoid α ↔ well_founded ((<) : associates α → associates α → Prop)
⟨by apply wf_dvd_monoid.well_founded_associates, wf_dvd_monoid.of_well_founded_associates⟩
theorem
wf_dvd_monoid.iff_well_founded_associates
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associates", "cancel_comm_monoid_with_zero", "wf_dvd_monoid", "wf_dvd_monoid.well_founded_associates" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
unique_factorization_monoid (α : Type*) [cancel_comm_monoid_with_zero α] extends wf_dvd_monoid α : Prop
(irreducible_iff_prime : ∀ {a : α}, irreducible a ↔ prime a)
class
unique_factorization_monoid
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "cancel_comm_monoid_with_zero", "irreducible", "prime", "wf_dvd_monoid" ]
unique factorization monoids. These are defined as `cancel_comm_monoid_with_zero`s with well-founded strict divisibility relations, but this is equivalent to more familiar definitions: Each element (except zero) is uniquely represented as a multiset of irreducible factors. Uniqueness is only up to associated elements...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ufm_of_gcd_of_wf_dvd_monoid [cancel_comm_monoid_with_zero α] [wf_dvd_monoid α] [gcd_monoid α] : unique_factorization_monoid α
{ irreducible_iff_prime := λ _, gcd_monoid.irreducible_iff_prime .. ‹wf_dvd_monoid α› }
lemma
ufm_of_gcd_of_wf_dvd_monoid
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "cancel_comm_monoid_with_zero", "gcd_monoid", "gcd_monoid.irreducible_iff_prime", "unique_factorization_monoid", "wf_dvd_monoid" ]
Can't be an instance because it would cause a loop `ufm → wf_dvd_monoid → ufm → ...`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
associates.ufm [cancel_comm_monoid_with_zero α] [unique_factorization_monoid α] : unique_factorization_monoid (associates α)
{ irreducible_iff_prime := by { rw ← associates.irreducible_iff_prime_iff, apply unique_factorization_monoid.irreducible_iff_prime, } .. (wf_dvd_monoid.wf_dvd_monoid_associates : wf_dvd_monoid (associates α)) }
instance
associates.ufm
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associates", "associates.irreducible_iff_prime_iff", "cancel_comm_monoid_with_zero", "unique_factorization_monoid", "wf_dvd_monoid", "wf_dvd_monoid.wf_dvd_monoid_associates" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exists_prime_factors (a : α) : a ≠ 0 → ∃ f : multiset α, (∀b ∈ f, prime b) ∧ f.prod ~ᵤ a
by { simp_rw ← unique_factorization_monoid.irreducible_iff_prime, apply wf_dvd_monoid.exists_factors a }
theorem
unique_factorization_monoid.exists_prime_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "multiset", "prime", "wf_dvd_monoid.exists_factors" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
induction_on_prime {P : α → Prop} (a : α) (h₁ : P 0) (h₂ : ∀ x : α, is_unit x → P x) (h₃ : ∀ a p : α, a ≠ 0 → prime p → P a → P (p * a)) : P a
begin simp_rw ← unique_factorization_monoid.irreducible_iff_prime at h₃, exact wf_dvd_monoid.induction_on_irreducible a h₁ h₂ h₃, end
lemma
unique_factorization_monoid.induction_on_prime
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "is_unit", "prime", "wf_dvd_monoid.induction_on_irreducible" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prime_factors_unique [cancel_comm_monoid_with_zero α] : ∀ {f g : multiset α}, (∀ x ∈ f, prime x) → (∀ x ∈ g, prime x) → f.prod ~ᵤ g.prod → multiset.rel associated f g
by haveI := classical.dec_eq α; exact λ f, multiset.induction_on f (λ g _ hg h, multiset.rel_zero_left.2 $ multiset.eq_zero_of_forall_not_mem $ λ x hx, have is_unit g.prod, by simpa [associated_one_iff_is_unit] using h.symm, (hg x hx).not_unit $ is_unit_iff_dvd_one.2 $ (multiset.dvd_prod hx).trans...
lemma
prime_factors_unique
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated", "associated.of_mul_left", "associated_one_iff_is_unit", "cancel_comm_monoid_with_zero", "classical.dec_eq", "exists_associated_mem_of_dvd_prod", "ih", "is_unit", "multiset", "multiset.cons_erase", "multiset.dvd_prod", "multiset.eq_zero_of_forall_not_mem", "multiset.induction_on...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
factors_unique {f g : multiset α} (hf : ∀ x ∈ f, irreducible x) (hg : ∀ x ∈ g, irreducible x) (h : f.prod ~ᵤ g.prod) : multiset.rel associated f g
prime_factors_unique (λ x hx, irreducible_iff_prime.mp (hf x hx)) (λ x hx, irreducible_iff_prime.mp (hg x hx)) h
lemma
unique_factorization_monoid.factors_unique
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated", "irreducible", "multiset", "multiset.rel", "prime_factors_unique" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prime_factors_irreducible [cancel_comm_monoid_with_zero α] {a : α} {f : multiset α} (ha : irreducible a) (pfa : (∀ b ∈ f, prime b) ∧ f.prod ~ᵤ a) : ∃ p, a ~ᵤ p ∧ f = {p}
begin haveI := classical.dec_eq α, refine multiset.induction_on f (λ h, (ha.not_unit (associated_one_iff_is_unit.1 (associated.symm h))).elim) _ pfa.2 pfa.1, rintros p s _ ⟨u, hu⟩ hs, use p, have hs0 : s = 0, { by_contra hs0, obtain ⟨q, hq⟩ := multiset.exists_mem_of_ne_zero hs0, apply (hs q (by ...
lemma
prime_factors_irreducible
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated.symm", "by_contra", "cancel_comm_monoid_with_zero", "classical.dec_eq", "irreducible", "is_unit_of_mul_is_unit_left", "mul_assoc", "mul_comm", "mul_one", "mul_right_comm", "multiset", "multiset.cons_erase", "multiset.exists_mem_of_ne_zero", "multiset.induction_on", "multiset....
If an irreducible has a prime factorization, then it is an associate of one of its prime factors.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
wf_dvd_monoid.of_exists_prime_factors : wf_dvd_monoid α
⟨begin classical, refine rel_hom_class.well_founded (rel_hom.mk _ _ : (dvd_not_unit : α → α → Prop) →r ((<) : ℕ∞ → ℕ∞ → Prop)) (with_top.well_founded_lt nat.lt_wf), { intro a, by_cases h : a = 0, { exact ⊤ }, exact (classical.some (pf a h)).card }, rintros a b ⟨ane0, ⟨c, hc, b_eq⟩⟩, rw dif_ne...
lemma
wf_dvd_monoid.of_exists_prime_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated.mul_mul", "con", "dvd_not_unit", "lt_top_iff_ne_top", "mul_zero", "multiset.card", "multiset.card_add", "multiset.card_eq_card_of_rel", "multiset.mem_add", "multiset.prod_add", "multiset.prod_zero", "prime_factors_unique", "rel_hom_class.well_founded", "wf_dvd_monoid", "with_...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
irreducible_iff_prime_of_exists_prime_factors {p : α} : irreducible p ↔ prime p
begin by_cases hp0 : p = 0, { simp [hp0] }, refine ⟨λ h, _, prime.irreducible⟩, obtain ⟨f, hf⟩ := pf p hp0, obtain ⟨q, hq, rfl⟩ := prime_factors_irreducible h hf, rw hq.prime_iff, exact hf.1 q (multiset.mem_singleton_self _) end
lemma
irreducible_iff_prime_of_exists_prime_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "irreducible", "multiset.mem_singleton_self", "prime", "prime_factors_irreducible" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
unique_factorization_monoid.of_exists_prime_factors : unique_factorization_monoid α
{ irreducible_iff_prime := λ _, irreducible_iff_prime_of_exists_prime_factors pf, .. wf_dvd_monoid.of_exists_prime_factors pf }
theorem
unique_factorization_monoid.of_exists_prime_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "irreducible_iff_prime_of_exists_prime_factors", "unique_factorization_monoid", "wf_dvd_monoid.of_exists_prime_factors" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
unique_factorization_monoid.iff_exists_prime_factors [cancel_comm_monoid_with_zero α] : unique_factorization_monoid α ↔ (∀ (a : α), a ≠ 0 → ∃ f : multiset α, (∀b ∈ f, prime b) ∧ f.prod ~ᵤ a)
⟨λ h, @unique_factorization_monoid.exists_prime_factors _ _ h, unique_factorization_monoid.of_exists_prime_factors⟩
theorem
unique_factorization_monoid.iff_exists_prime_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "cancel_comm_monoid_with_zero", "multiset", "prime", "unique_factorization_monoid", "unique_factorization_monoid.exists_prime_factors" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_equiv.unique_factorization_monoid (e : α ≃* β) (hα : unique_factorization_monoid α) : unique_factorization_monoid β
begin rw unique_factorization_monoid.iff_exists_prime_factors at hα ⊢, intros a ha, obtain ⟨w,hp,u,h⟩ := hα (e.symm a) (λ h, ha $ by { convert ← map_zero e, simp [← h] }), exact ⟨ w.map e, λ b hb, let ⟨c,hc,he⟩ := multiset.mem_map.1 hb in he ▸ e.prime_iff.1 (hp c hc), units.map e.to_monoid_hom u, by {...
lemma
mul_equiv.unique_factorization_monoid
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "multiset.prod_hom", "unique_factorization_monoid", "unique_factorization_monoid.iff_exists_prime_factors", "units.map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_equiv.unique_factorization_monoid_iff (e : α ≃* β) : unique_factorization_monoid α ↔ unique_factorization_monoid β
⟨ e.unique_factorization_monoid, e.symm.unique_factorization_monoid ⟩
lemma
mul_equiv.unique_factorization_monoid_iff
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "unique_factorization_monoid" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
irreducible_iff_prime_of_exists_unique_irreducible_factors [cancel_comm_monoid_with_zero α] (eif : ∀ (a : α), a ≠ 0 → ∃ f : multiset α, (∀b ∈ f, irreducible b) ∧ f.prod ~ᵤ a) (uif : ∀ (f g : multiset α), (∀ x ∈ f, irreducible x) → (∀ x ∈ g, irreducible x) → f.prod ~ᵤ g.prod → multiset.rel associated f g) (p...
⟨by letI := classical.dec_eq α; exact λ hpi, ⟨hpi.ne_zero, hpi.1, λ a b ⟨x, hx⟩, if hab0 : a * b = 0 then (eq_zero_or_eq_zero_of_mul_eq_zero hab0).elim (λ ha0, by simp [ha0]) (λ hb0, by simp [hb0]) else have hx0 : x ≠ 0, from λ hx0, by simp * at *, have ha0 : ...
theorem
irreducible_iff_prime_of_exists_unique_irreducible_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated", "cancel_comm_monoid_with_zero", "classical.dec_eq", "irreducible", "left_ne_zero_of_mul", "multiset", "multiset.dvd_prod", "multiset.exists_mem_of_rel_of_mem", "multiset.mem_cons_self", "multiset.prod", "multiset.prod_add", "multiset.prod_cons", "multiset.rel", "prime", "ri...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
unique_factorization_monoid.of_exists_unique_irreducible_factors [cancel_comm_monoid_with_zero α] (eif : ∀ (a : α), a ≠ 0 → ∃ f : multiset α, (∀b ∈ f, irreducible b) ∧ f.prod ~ᵤ a) (uif : ∀ (f g : multiset α), (∀ x ∈ f, irreducible x) → (∀ x ∈ g, irreducible x) → f.prod ~ᵤ g.prod → multiset.rel associated f...
unique_factorization_monoid.of_exists_prime_factors (by { convert eif, simp_rw irreducible_iff_prime_of_exists_unique_irreducible_factors eif uif })
theorem
unique_factorization_monoid.of_exists_unique_irreducible_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated", "cancel_comm_monoid_with_zero", "irreducible", "irreducible_iff_prime_of_exists_unique_irreducible_factors", "multiset", "multiset.rel", "unique_factorization_monoid", "unique_factorization_monoid.of_exists_prime_factors" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
factors (a : α) : multiset α
if h : a = 0 then 0 else classical.some (unique_factorization_monoid.exists_prime_factors a h)
def
unique_factorization_monoid.factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "multiset", "unique_factorization_monoid.exists_prime_factors" ]
Noncomputably determines the multiset of prime factors.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
factors_prod {a : α} (ane0 : a ≠ 0) : associated (factors a).prod a
begin rw [factors, dif_neg ane0], exact (classical.some_spec (exists_prime_factors a ane0)).2 end
theorem
unique_factorization_monoid.factors_prod
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "associated" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ne_zero_of_mem_factors {p a : α} (h : p ∈ factors a) : a ≠ 0
begin intro ha, rw [factors, dif_pos ha] at h, exact multiset.not_mem_zero _ h end
lemma
unique_factorization_monoid.ne_zero_of_mem_factors
ring_theory
src/ring_theory/unique_factorization_domain.lean
[ "algebra.big_operators.associated", "algebra.gcd_monoid.basic", "data.finsupp.multiset", "ring_theory.noetherian", "ring_theory.multiplicity" ]
[ "multiset.not_mem_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83