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map_equiv_trans (e₁ : R ≃+* S) (e₂ : S ≃+* T) : map_equiv (e₁.trans e₂) = (map_equiv e₁).trans (map_equiv e₂)
ring_equiv.to_ring_hom_injective $ map_comp (e₁ : R →+* S) (e₂ : S →+* T)
lemma
local_ring.residue_field.map_equiv_trans
ring_theory.ideal
src/ring_theory/ideal/local_ring.lean
[ "algebra.algebra.basic", "ring_theory.ideal.operations", "ring_theory.jacobson_ideal", "logic.equiv.transfer_instance" ]
[ "map_comp", "ring_equiv.to_ring_hom_injective" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_equiv_refl : map_equiv (ring_equiv.refl R) = ring_equiv.refl _
ring_equiv.to_ring_hom_injective map_id
lemma
local_ring.residue_field.map_equiv_refl
ring_theory.ideal
src/ring_theory/ideal/local_ring.lean
[ "algebra.algebra.basic", "ring_theory.ideal.operations", "ring_theory.jacobson_ideal", "logic.equiv.transfer_instance" ]
[ "map_id", "ring_equiv.refl", "ring_equiv.to_ring_hom_injective" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_aut : ring_aut R →* ring_aut (local_ring.residue_field R)
{ to_fun := map_equiv, map_mul' := λ e₁ e₂, map_equiv_trans e₂ e₁, map_one' := map_equiv_refl }
def
local_ring.residue_field.map_aut
ring_theory.ideal
src/ring_theory/ideal/local_ring.lean
[ "algebra.algebra.basic", "ring_theory.ideal.operations", "ring_theory.jacobson_ideal", "logic.equiv.transfer_instance" ]
[ "local_ring.residue_field", "ring_aut" ]
The group homomorphism from `ring_aut R` to `ring_aut k` where `k` is the residue field of `R`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
residue_smul (g : G) (r : R) : residue R (g • r) = g • residue R r
rfl
lemma
local_ring.residue_field.residue_smul
ring_theory.ideal
src/ring_theory/ideal/local_ring.lean
[ "algebra.algebra.basic", "ring_theory.ideal.operations", "ring_theory.jacobson_ideal", "logic.equiv.transfer_instance" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ker_eq_maximal_ideal [field K] (φ : R →+* K) (hφ : function.surjective φ) : φ.ker = maximal_ideal R
local_ring.eq_maximal_ideal $ (ring_hom.ker_is_maximal_of_surjective φ) hφ
lemma
local_ring.ker_eq_maximal_ideal
ring_theory.ideal
src/ring_theory/ideal/local_ring.lean
[ "algebra.algebra.basic", "ring_theory.ideal.operations", "ring_theory.jacobson_ideal", "logic.equiv.transfer_instance" ]
[ "field", "local_ring.eq_maximal_ideal", "ring_hom.ker_is_maximal_of_surjective" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_local_ring_hom_residue : is_local_ring_hom (local_ring.residue R)
begin constructor, intros a ha, by_contra, erw ideal.quotient.eq_zero_iff_mem.mpr ((local_ring.mem_maximal_ideal _).mpr h) at ha, exact ha.ne_zero rfl, end
lemma
local_ring.is_local_ring_hom_residue
ring_theory.ideal
src/ring_theory/ideal/local_ring.lean
[ "algebra.algebra.basic", "ring_theory.ideal.operations", "ring_theory.jacobson_ideal", "logic.equiv.transfer_instance" ]
[ "by_contra", "is_local_ring_hom", "local_ring.mem_maximal_ideal", "local_ring.residue" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_ring.maximal_ideal_eq_bot {R : Type*} [field R] : local_ring.maximal_ideal R = ⊥
local_ring.is_field_iff_maximal_ideal_eq.mp (field.to_is_field R)
lemma
local_ring.maximal_ideal_eq_bot
ring_theory.ideal
src/ring_theory/ideal/local_ring.lean
[ "algebra.algebra.basic", "ring_theory.ideal.operations", "ring_theory.jacobson_ideal", "logic.equiv.transfer_instance" ]
[ "field", "field.to_is_field", "local_ring.maximal_ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_ring {A B : Type*} [comm_semiring A] [local_ring A] [comm_semiring B] (e : A ≃+* B) : local_ring B
begin haveI := e.symm.to_equiv.nontrivial, exact local_ring.of_surjective (e : A →+* B) e.surjective end
lemma
ring_equiv.local_ring
ring_theory.ideal
src/ring_theory/ideal/local_ring.lean
[ "algebra.algebra.basic", "ring_theory.ideal.operations", "ring_theory.jacobson_ideal", "logic.equiv.transfer_instance" ]
[ "comm_semiring", "local_ring", "local_ring.of_surjective" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.minimal_primes : set (ideal R)
minimals (≤) { p | p.is_prime ∧ I ≤ p }
def
ideal.minimal_primes
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "ideal", "minimals" ]
`I.minimal_primes` is the set of ideals that are minimal primes over `I`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
minimal_primes (R : Type*) [comm_ring R] : set (ideal R)
ideal.minimal_primes ⊥
def
minimal_primes
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "comm_ring", "ideal", "ideal.minimal_primes" ]
`minimal_primes R` is the set of minimal primes of `R`. This is defined as `ideal.minimal_primes ⊥`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.exists_minimal_primes_le [J.is_prime] (e : I ≤ J) : ∃ p ∈ I.minimal_primes, p ≤ J
begin suffices : ∃ m ∈ { p : (ideal R)ᵒᵈ | ideal.is_prime p ∧ I ≤ order_dual.of_dual p }, (order_dual.to_dual J) ≤ m ∧ ∀ z ∈ { p : (ideal R)ᵒᵈ | ideal.is_prime p ∧ I ≤ p }, m ≤ z → z = m, { obtain ⟨p, h₁, h₂, h₃⟩ := this, simp_rw ← @eq_comm _ p at h₃, exact ⟨p, ⟨h₁, λ a b c, (h₃ a b c).le⟩, h₂⟩ },...
lemma
ideal.exists_minimal_primes_le
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "Inf_le", "ideal", "ideal.is_prime", "le_Inf", "order_dual.le_to_dual", "order_dual.of_dual", "order_dual.of_dual_to_dual", "order_dual.to_dual", "zorn_nonempty_partial_order₀" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.radical_minimal_primes : I.radical.minimal_primes = I.minimal_primes
begin rw [ideal.minimal_primes, ideal.minimal_primes], congr, ext p, exact ⟨λ ⟨a, b⟩, ⟨a, ideal.le_radical.trans b⟩, λ ⟨a, b⟩, ⟨a, a.radical_le_iff.mpr b⟩⟩, end
lemma
ideal.radical_minimal_primes
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "ideal.minimal_primes" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.Inf_minimal_primes : Inf I.minimal_primes = I.radical
begin rw I.radical_eq_Inf, apply le_antisymm, { intros x hx, rw ideal.mem_Inf at hx ⊢, rintros J ⟨e, hJ⟩, resetI, obtain ⟨p, hp, hp'⟩ := ideal.exists_minimal_primes_le e, exact hp' (hx hp) }, { apply Inf_le_Inf _, intros I hI, exact hI.1.symm }, end
lemma
ideal.Inf_minimal_primes
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "Inf_le_Inf", "ideal.exists_minimal_primes_le", "ideal.mem_Inf" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.exists_comap_eq_of_mem_minimal_primes_of_injective {f : R →+* S} (hf : function.injective f) (p ∈ minimal_primes R) : ∃ p' : ideal S, p'.is_prime ∧ p'.comap f = p
begin haveI := H.1.1, haveI : nontrivial (localization (submonoid.map f p.prime_compl)), { refine ⟨⟨1, 0, _⟩⟩, convert (is_localization.map_injective_of_injective p.prime_compl (localization.at_prime p) (localization $ p.prime_compl.map f) hf).ne one_ne_zero, { rw map_one }, { rw map_zero } }, obt...
lemma
ideal.exists_comap_eq_of_mem_minimal_primes_of_injective
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "algebra_map", "by_contra", "ideal", "ideal.comap_comap", "ideal.exists_maximal", "is_localization.map_comp", "is_localization.map_injective_of_injective", "is_unit.map", "localization", "localization.at_prime", "map_one", "minimal_primes", "nontrivial", "one_ne_zero", "submonoid.map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.exists_comap_eq_of_mem_minimal_primes {I : ideal S} (f : R →+* S) (p ∈ (I.comap f).minimal_primes) : ∃ p' : ideal S, p'.is_prime ∧ I ≤ p' ∧ p'.comap f = p
begin haveI := H.1.1, let f' := I^.quotient.mk^.comp f, have e : (I^.quotient.mk^.comp f).ker = I.comap f, { ext1, exact (submodule.quotient.mk_eq_zero _) }, have : (I^.quotient.mk^.comp f).ker^.quotient.mk^.ker ≤ p, { rw [ideal.mk_ker, e], exact H.1.2 }, obtain ⟨p', hp₁, hp₂⟩ := ideal.exists_comap_eq_of_...
lemma
ideal.exists_comap_eq_of_mem_minimal_primes
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "bot_le", "ideal", "ideal.comap", "ideal.comap_map_of_surjective", "ideal.comap_mono", "ideal.exists_comap_eq_of_mem_minimal_primes_of_injective", "ideal.is_prime.comap", "ideal.map_comap_of_surjective", "ideal.map_is_prime_of_surjective", "ideal.map_mono", "ideal.mk_ker", "ideal.quotient.mk_s...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.exists_minimal_primes_comap_eq {I : ideal S} (f : R →+* S) (p ∈ (I.comap f).minimal_primes) : ∃ p' ∈ I.minimal_primes, ideal.comap f p' = p
begin obtain ⟨p', h₁, h₂, h₃⟩ := ideal.exists_comap_eq_of_mem_minimal_primes f p H, resetI, obtain ⟨q, hq, hq'⟩ := ideal.exists_minimal_primes_le h₂, refine ⟨q, hq, eq.symm _⟩, haveI := hq.1.1, have := (ideal.comap_mono hq').trans_eq h₃, exact (H.2 ⟨infer_instance, ideal.comap_mono hq.1.2⟩ this).antisymm ...
lemma
ideal.exists_minimal_primes_comap_eq
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "ideal", "ideal.comap", "ideal.comap_mono", "ideal.exists_comap_eq_of_mem_minimal_primes", "ideal.exists_minimal_primes_le", "minimal_primes" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.mimimal_primes_comap_of_surjective {f : R →+* S} (hf : function.surjective f) {I J : ideal S} (h : J ∈ I.minimal_primes) : J.comap f ∈ (I.comap f).minimal_primes
begin haveI := h.1.1, refine ⟨⟨infer_instance, ideal.comap_mono h.1.2⟩, _⟩, rintros K ⟨hK, e₁⟩ e₂, have : f.ker ≤ K := (ideal.comap_mono bot_le).trans e₁, rw [← sup_eq_left.mpr this, ring_hom.ker_eq_comap_bot, ← ideal.comap_map_of_surjective f hf], apply ideal.comap_mono _, apply h.2 _ _, { exactI ⟨idea...
lemma
ideal.mimimal_primes_comap_of_surjective
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "bot_le", "ideal", "ideal.comap_map_of_surjective", "ideal.comap_mono", "ideal.le_map_of_comap_le_of_surjective", "ideal.map_le_of_le_comap", "minimal_primes", "ring_hom.ker_eq_comap_bot" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.comap_minimal_primes_eq_of_surjective {f : R →+* S} (hf : function.surjective f) (I : ideal S) : (I.comap f).minimal_primes = ideal.comap f '' I.minimal_primes
begin ext J, split, { intro H, obtain ⟨p, h, rfl⟩ := ideal.exists_minimal_primes_comap_eq f J H, exact ⟨p, h, rfl⟩ }, { rintros ⟨J, hJ, rfl⟩, exact ideal.mimimal_primes_comap_of_surjective hf hJ } end
lemma
ideal.comap_minimal_primes_eq_of_surjective
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "ideal", "ideal.comap", "ideal.exists_minimal_primes_comap_eq", "ideal.mimimal_primes_comap_of_surjective", "minimal_primes" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.minimal_primes_eq_comap : I.minimal_primes = ideal.comap I^.quotient.mk '' minimal_primes (R ⧸ I)
begin rw [minimal_primes, ← ideal.comap_minimal_primes_eq_of_surjective ideal.quotient.mk_surjective, ← ring_hom.ker_eq_comap_bot, ideal.mk_ker], end
lemma
ideal.minimal_primes_eq_comap
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[ "ideal.comap", "ideal.comap_minimal_primes_eq_of_surjective", "ideal.mk_ker", "ideal.quotient.mk_surjective", "minimal_primes", "ring_hom.ker_eq_comap_bot" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.minimal_primes_eq_subsingleton (hI : I.is_primary) : I.minimal_primes = {I.radical}
begin ext J, split, { exact λ H, let e := H.1.1.radical_le_iff.mpr H.1.2 in (H.2 ⟨ideal.is_prime_radical hI, ideal.le_radical⟩ e).antisymm e }, { rintro (rfl : J = I.radical), exact ⟨⟨ideal.is_prime_radical hI, ideal.le_radical⟩, λ _ H _, H.1.radical_le_iff.mpr H.2⟩ } end
lemma
ideal.minimal_primes_eq_subsingleton
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.minimal_primes_eq_subsingleton_self [I.is_prime] : I.minimal_primes = {I}
begin ext J, split, { exact λ H, (H.2 ⟨infer_instance, rfl.le⟩ H.1.2).antisymm H.1.2 }, { unfreezingI { rintro (rfl : J = I) }, refine ⟨⟨infer_instance, rfl.le⟩, λ _ h _, h.2⟩ }, end
lemma
ideal.minimal_primes_eq_subsingleton_self
ring_theory.ideal
src/ring_theory/ideal/minimal_prime.lean
[ "ring_theory.localization.at_prime", "order.minimal" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
card_quot (S : submodule R M) : ℕ
add_subgroup.index S.to_add_subgroup
def
submodule.card_quot
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "submodule" ]
The cardinality of `(M ⧸ S)`, if `(M ⧸ S)` is finite, and `0` otherwise. This is used to define the absolute ideal norm `ideal.abs_norm`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
card_quot_apply (S : submodule R M) [fintype (M ⧸ S)] : card_quot S = fintype.card (M ⧸ S)
add_subgroup.index_eq_card _
lemma
submodule.card_quot_apply
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "fintype", "fintype.card", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
card_quot_bot [infinite M] : card_quot (⊥ : submodule R M) = 0
add_subgroup.index_bot.trans nat.card_eq_zero_of_infinite
lemma
submodule.card_quot_bot
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "infinite", "nat.card_eq_zero_of_infinite", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
card_quot_top : card_quot (⊤ : submodule R M) = 1
add_subgroup.index_top
lemma
submodule.card_quot_top
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
card_quot_eq_one_iff {P : submodule R M} : card_quot P = 1 ↔ P = ⊤
add_subgroup.index_eq_one.trans (by simp [set_like.ext_iff])
lemma
submodule.card_quot_eq_one_iff
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "set_like.ext_iff", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
card_quot_mul_of_coprime [is_dedekind_domain S] [module.free ℤ S] [module.finite ℤ S] {I J : ideal S} (coprime : I ⊔ J = ⊤) : card_quot (I * J) = card_quot I * card_quot J
begin let b := module.free.choose_basis ℤ S, casesI is_empty_or_nonempty (module.free.choose_basis_index ℤ S), { haveI : subsingleton S := function.surjective.subsingleton b.repr.to_equiv.symm.surjective, nontriviality S, exfalso, exact not_nontrivial_iff_subsingleton.mpr ‹subsingleton S› ‹nontrivial ...
lemma
card_quot_mul_of_coprime
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "classical.dec_eq", "fintype.card_prod", "function.surjective.subsingleton", "ideal", "ideal.quotient_mul_equiv_quotient_prod", "infinite", "infinite.of_surjective", "is_dedekind_domain", "is_empty_or_nonempty", "module.finite", "module.free", "module.free.choose_basis", "module.free.choose_...
Multiplicity of the ideal norm, for coprime ideals. This is essentially just a repackaging of the Chinese Remainder Theorem.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.mul_add_mem_pow_succ_inj (P : ideal S) {i : ℕ} (a d d' e e' : S) (a_mem : a ∈ P ^ i) (e_mem : e ∈ P ^ (i + 1)) (e'_mem : e' ∈ P ^ (i + 1)) (h : d - d' ∈ P) : (a * d + e) - (a * d' + e') ∈ P ^ (i + 1)
begin have : a * d - a * d' ∈ P ^ (i + 1), { convert ideal.mul_mem_mul a_mem h; simp [mul_sub, pow_succ, mul_comm] }, convert ideal.add_mem _ this (ideal.sub_mem _ e_mem e'_mem), ring, end
lemma
ideal.mul_add_mem_pow_succ_inj
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "ideal.add_mem", "ideal.mul_mem_mul", "ideal.sub_mem", "mul_comm", "pow_succ", "ring" ]
If the `d` from `ideal.exists_mul_add_mem_pow_succ` is unique, up to `P`, then so are the `c`s, up to `P ^ (i + 1)`. Inspired by [Neukirch], proposition 6.1
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.exists_mul_add_mem_pow_succ [is_dedekind_domain S] {i : ℕ} (a c : S) (a_mem : a ∈ P ^ i) (a_not_mem : a ∉ P ^ (i + 1)) (c_mem : c ∈ P ^ i) : ∃ (d : S) (e ∈ P ^ (i + 1)), a * d + e = c
begin suffices eq_b : P ^ i = ideal.span {a} ⊔ P ^ (i + 1), { rw eq_b at c_mem, simp only [mul_comm a], exact ideal.mem_span_singleton_sup.mp c_mem }, refine (ideal.eq_prime_pow_of_succ_lt_of_le hP (lt_of_le_of_ne le_sup_right _) (sup_le (ideal.span_le.mpr (set.singleton_subset_iff.mpr a_mem)) ...
lemma
ideal.exists_mul_add_mem_pow_succ
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal.eq_prime_pow_of_succ_lt_of_le", "ideal.pow_succ_lt_pow", "ideal.span", "is_dedekind_domain", "le_sup_right", "mul_comm", "sup_le" ]
If `a ∈ P^i \ P^(i+1)` and `c ∈ P^i`, then `a * d + e = c` for `e ∈ P^(i+1)`. `ideal.mul_add_mem_pow_succ_unique` shows the choice of `d` is unique, up to `P`. Inspired by [Neukirch], proposition 6.1
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.mem_prime_of_mul_mem_pow [is_dedekind_domain S] {P : ideal S} [P_prime : P.is_prime] (hP : P ≠ ⊥) {i : ℕ} {a b : S} (a_not_mem : a ∉ P ^ (i + 1)) (ab_mem : a * b ∈ P ^ (i + 1)) : b ∈ P
begin simp only [← ideal.span_singleton_le_iff_mem, ← ideal.dvd_iff_le, pow_succ, ← ideal.span_singleton_mul_span_singleton] at a_not_mem ab_mem ⊢, exact (prime_pow_succ_dvd_mul (ideal.prime_of_is_prime hP P_prime) ab_mem).resolve_left a_not_mem end
lemma
ideal.mem_prime_of_mul_mem_pow
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "ideal.dvd_iff_le", "ideal.prime_of_is_prime", "ideal.span_singleton_le_iff_mem", "ideal.span_singleton_mul_span_singleton", "is_dedekind_domain", "pow_succ", "prime_pow_succ_dvd_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.mul_add_mem_pow_succ_unique [is_dedekind_domain S] {i : ℕ} (a d d' e e' : S) (a_not_mem : a ∉ P ^ (i + 1)) (e_mem : e ∈ P ^ (i + 1)) (e'_mem : e' ∈ P ^ (i + 1)) (h : (a * d + e) - (a * d' + e') ∈ P ^ (i + 1)) : d - d' ∈ P
begin have : e' - e ∈ P ^ (i + 1) := ideal.sub_mem _ e'_mem e_mem, have h' : a * (d - d') ∈ P ^ (i + 1), { convert ideal.add_mem _ h (ideal.sub_mem _ e'_mem e_mem), ring }, exact ideal.mem_prime_of_mul_mem_pow hP a_not_mem h' end
lemma
ideal.mul_add_mem_pow_succ_unique
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal.add_mem", "ideal.mem_prime_of_mul_mem_pow", "ideal.sub_mem", "is_dedekind_domain", "ring" ]
The choice of `d` in `ideal.exists_mul_add_mem_pow_succ` is unique, up to `P`. Inspired by [Neukirch], proposition 6.1
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
card_quot_pow_of_prime [is_dedekind_domain S] [module.finite ℤ S] [module.free ℤ S] {i : ℕ} : card_quot (P ^ i) = card_quot P ^ i
begin let b := module.free.choose_basis ℤ S, classical, induction i with i ih, { simp }, letI := ideal.fintype_quotient_of_free_of_ne_bot (P ^ i.succ) (pow_ne_zero _ hP), letI := ideal.fintype_quotient_of_free_of_ne_bot (P ^ i) (pow_ne_zero _ hP), letI := ideal.fintype_quotient_of_free_of_ne_bot P hP, h...
lemma
card_quot_pow_of_prime
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "equiv.of_bijective", "fintype.card_eq", "ideal.exists_mul_add_mem_pow_succ", "ideal.fintype_quotient_of_free_of_ne_bot", "ideal.mul_add_mem_pow_succ_inj", "ideal.mul_add_mem_pow_succ_unique", "ideal.mul_mem_right", "ideal.pow_succ_lt_pow", "ideal.quotient.eq", "ideal.quotient.mk_eq_mk", "ih", ...
Multiplicity of the ideal norm, for powers of prime ideals.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
card_quot_mul [is_dedekind_domain S] [module.free ℤ S] [module.finite ℤ S] (I J : ideal S) : card_quot (I * J) = card_quot I * card_quot J
begin let b := module.free.choose_basis ℤ S, casesI is_empty_or_nonempty (module.free.choose_basis_index ℤ S), { haveI : subsingleton S := function.surjective.subsingleton b.repr.to_equiv.symm.surjective, nontriviality S, exfalso, exact not_nontrivial_iff_subsingleton.mpr ‹subsingleton S› ‹nontrivial ...
theorem
card_quot_mul
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "card_quot_mul_of_coprime", "card_quot_pow_of_prime", "function.surjective.subsingleton", "ideal", "ideal.is_prime", "ideal.is_prime_of_prime", "ideal.mul_top", "infinite", "infinite.of_surjective", "is_dedekind_domain", "is_empty_or_nonempty", "le_sup_left", "le_sup_right", "module.finite...
Multiplicativity of the ideal norm in number rings.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ideal.abs_norm [infinite S] [is_dedekind_domain S] [module.free ℤ S] [module.finite ℤ S] : ideal S →*₀ ℕ
{ to_fun := submodule.card_quot, map_mul' := λ I J, by rw card_quot_mul, map_one' := by rw [ideal.one_eq_top, card_quot_top], map_zero' := by rw [ideal.zero_eq_bot, card_quot_bot] }
def
ideal.abs_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "card_quot_mul", "ideal", "ideal.one_eq_top", "ideal.zero_eq_bot", "infinite", "is_dedekind_domain", "module.finite", "module.free", "submodule.card_quot" ]
The absolute norm of the ideal `I : ideal R` is the cardinality of the quotient `R ⧸ I`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_apply (I : ideal S) : abs_norm I = card_quot I
rfl
lemma
ideal.abs_norm_apply
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_bot : abs_norm (⊥ : ideal S) = 0
by rw [← ideal.zero_eq_bot, _root_.map_zero]
lemma
ideal.abs_norm_bot
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "ideal", "ideal.zero_eq_bot" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_top : abs_norm (⊤ : ideal S) = 1
by rw [← ideal.one_eq_top, _root_.map_one]
lemma
ideal.abs_norm_top
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "ideal", "ideal.one_eq_top" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_eq_one_iff {I : ideal S} : abs_norm I = 1 ↔ I = ⊤
by rw [abs_norm_apply, card_quot_eq_one_iff]
lemma
ideal.abs_norm_eq_one_iff
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_ne_zero_iff (I : ideal S) : ideal.abs_norm I ≠ 0 ↔ finite (S ⧸ I)
⟨λ h,nat.finite_of_card_ne_zero h, λ h, (@add_subgroup.finite_index_of_finite_quotient _ _ _ h).finite_index⟩
lemma
ideal.abs_norm_ne_zero_iff
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "finite", "ideal", "ideal.abs_norm", "nat.finite_of_card_ne_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nat_abs_det_equiv (I : ideal S) {E : Type*} [add_equiv_class E S I] (e : E) : int.nat_abs (linear_map.det ((submodule.subtype I).restrict_scalars ℤ ∘ₗ add_monoid_hom.to_int_linear_map (e : S →+ I))) = ideal.abs_norm I
begin -- `S ⧸ I` might be infinite if `I = ⊥`, but then `e` can't be an equiv. by_cases hI : I = ⊥, { unfreezingI { subst hI }, have : (1 : S) ≠ 0 := one_ne_zero, have : (1 : S) = 0 := equiv_like.injective e (subsingleton.elim _ _), contradiction }, let ι := module.free.choose_basis_index ℤ S, le...
theorem
ideal.nat_abs_det_equiv
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "add_equiv.to_int_linear_equiv", "add_equiv_class", "add_monoid_hom.to_int_linear_map", "basis.repr_self", "classical.dec_eq", "equiv.refl", "equiv.refl_apply", "equiv_like.injective", "finset.univ", "finsupp.single_eq_of_ne", "finsupp.single_eq_same", "finsupp.smul_single", "f...
Let `e : S ≃ I` be an additive isomorphism (therefore a `ℤ`-linear equiv). Then an alternative way to compute the norm of `I` is given by taking the determinant of `e`. See `nat_abs_det_basis_change` for a more familiar formulation of this result.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nat_abs_det_basis_change {ι : Type*} [fintype ι] [decidable_eq ι] (b : basis ι ℤ S) (I : ideal S) (bI : basis ι ℤ I) : (b.det (coe ∘ bI)).nat_abs = ideal.abs_norm I
begin let e := b.equiv bI (equiv.refl _), calc (b.det ((submodule.subtype I).restrict_scalars ℤ ∘ bI)).nat_abs = (linear_map.det ((submodule.subtype I).restrict_scalars ℤ ∘ₗ (e : S →ₗ[ℤ] I))).nat_abs : by rw basis.det_comp_basis ... = _ : nat_abs_det_equiv I e end
theorem
ideal.nat_abs_det_basis_change
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "basis", "basis.det_comp_basis", "equiv.refl", "fintype", "ideal", "ideal.abs_norm", "linear_map.det", "restrict_scalars", "submodule.subtype" ]
Let `b` be a basis for `S` over `ℤ` and `bI` a basis for `I` over `ℤ` of the same dimension. Then an alternative way to compute the norm of `I` is given by taking the determinant of `bI` over `b`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_span_singleton (r : S) : abs_norm (span ({r} : set S)) = (algebra.norm ℤ r).nat_abs
begin rw algebra.norm_apply, by_cases hr : r = 0, { simp only [hr, ideal.span_zero, algebra.coe_lmul_eq_mul, eq_self_iff_true, ideal.abs_norm_bot, linear_map.det_zero'', set.singleton_zero, _root_.map_zero, int.nat_abs_zero] }, letI := ideal.fintype_quotient_of_free_of_ne_bot (span {r}) (mt span_singleton...
lemma
ideal.abs_norm_span_singleton
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "algebra.coe_lmul_eq_mul", "algebra.norm", "algebra.norm_apply", "equiv.refl", "ideal.abs_norm_bot", "ideal.fintype_quotient_of_free_of_ne_bot", "ideal.span_zero", "linear_map.det_zero''", "module.free.choose_basis" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_dvd_abs_norm_of_le {I J : ideal S} (h : J ≤ I) : I.abs_norm ∣ J.abs_norm
map_dvd abs_norm (dvd_iff_le.mpr h)
lemma
ideal.abs_norm_dvd_abs_norm_of_le
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "ideal", "map_dvd" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_dvd_norm_of_mem {I : ideal S} {x : S} (h : x ∈ I) : ↑I.abs_norm ∣ algebra.norm ℤ x
begin rw [← int.dvd_nat_abs, ← abs_norm_span_singleton x, int.coe_nat_dvd], exact abs_norm_dvd_abs_norm_of_le ((span_singleton_le_iff_mem _).mpr h) end
lemma
ideal.abs_norm_dvd_norm_of_mem
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm", "ideal", "int.coe_nat_dvd", "int.dvd_nat_abs" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_span_insert (r : S) (s : set S) : abs_norm (span (insert r s)) ∣ gcd (abs_norm (span s)) (algebra.norm ℤ r).nat_abs
(dvd_gcd_iff _ _ _).mpr ⟨abs_norm_dvd_abs_norm_of_le (span_mono (set.subset_insert _ _)), trans (abs_norm_dvd_abs_norm_of_le (span_mono (set.singleton_subset_iff.mpr (set.mem_insert _ _)))) (by rw abs_norm_span_singleton)⟩
lemma
ideal.abs_norm_span_insert
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "algebra.norm", "dvd_gcd_iff", "set.mem_insert", "set.subset_insert" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
irreducible_of_irreducible_abs_norm {I : ideal S} (hI : irreducible I.abs_norm) : irreducible I
irreducible_iff.mpr ⟨λ h, hI.not_unit (by simpa only [ideal.is_unit_iff, nat.is_unit_iff, abs_norm_eq_one_iff] using h), by rintro a b rfl; simpa only [ideal.is_unit_iff, nat.is_unit_iff, abs_norm_eq_one_iff] using hI.is_unit_or_is_unit (_root_.map_mul abs_norm a b)⟩
lemma
ideal.irreducible_of_irreducible_abs_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "ideal", "ideal.is_unit_iff", "irreducible", "nat.is_unit_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_prime_of_irreducible_abs_norm {I : ideal S} (hI : irreducible I.abs_norm) : I.is_prime
is_prime_of_prime (unique_factorization_monoid.irreducible_iff_prime.mp (irreducible_of_irreducible_abs_norm hI))
lemma
ideal.is_prime_of_irreducible_abs_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "irreducible" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prime_of_irreducible_abs_norm_span {a : S} (ha : a ≠ 0) (hI : irreducible (ideal.span ({a} : set S)).abs_norm) : prime a
(ideal.span_singleton_prime ha).mp (is_prime_of_irreducible_abs_norm hI)
lemma
ideal.prime_of_irreducible_abs_norm_span
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "abs_norm", "ideal.span", "ideal.span_singleton_prime", "irreducible", "prime" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
abs_norm_mem (I : ideal S) : ↑I.abs_norm ∈ I
by rw [abs_norm_apply, card_quot, ← ideal.quotient.eq_zero_iff_mem, map_nat_cast, quotient.index_eq_zero]
lemma
ideal.abs_norm_mem
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "ideal.quotient.eq_zero_iff_mem", "map_nat_cast" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_singleton_abs_norm_le (I : ideal S) : ideal.span { (ideal.abs_norm I : S) } ≤ I
by simp only [ideal.span_le, set.singleton_subset_iff, set_like.mem_coe, ideal.abs_norm_mem I]
lemma
ideal.span_singleton_abs_norm_le
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "ideal.abs_norm", "ideal.abs_norm_mem", "ideal.span", "ideal.span_le", "set.singleton_subset_iff", "set_like.mem_coe" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
finite_set_of_abs_norm_eq [char_zero S] {n : ℕ} (hn : 0 < n) : { I : ideal S | ideal.abs_norm I = n }.finite
begin let f := λ I : ideal S, ideal.map (ideal.quotient.mk (@ideal.span S _ {n})) I, refine @set.finite.of_finite_image _ _ _ f _ _, { suffices : finite (S ⧸ @ideal.span S _ {n}), { let g := (coe : ideal (S ⧸ @ideal.span S _ {n}) → set (S ⧸ @ideal.span S _ {n})), refine @set.finite.of_finite_image _ _ _...
lemma
ideal.finite_set_of_abs_norm_eq
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm_eq_zero_iff", "char_zero", "finite", "ideal", "ideal.abs_norm", "ideal.comap", "ideal.map", "ideal.quotient.mk", "ideal.span", "int.nat_abs_eq_zero", "nat.cast_eq_zero", "set.finite'", "set.finite.of_finite_image", "set.finite.subset", "set.finite_univ", "set.subset_univ"...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm (I : ideal S) : ideal R
ideal.span (algebra.norm R '' (I : set S))
def
ideal.span_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm", "ideal", "ideal.span" ]
`ideal.span_norm R (I : ideal S)` is the ideal generated by mapping `algebra.norm R` over `I`. See also `ideal.rel_norm`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_bot [nontrivial S] [module.free R S] [module.finite R S] : span_norm R (⊥ : ideal S) = ⊥
span_eq_bot.mpr (λ x hx, by simpa using hx)
lemma
ideal.span_norm_bot
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "module.finite", "module.free", "nontrivial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_eq_bot_iff [is_domain R] [is_domain S] [module.free R S] [module.finite R S] {I : ideal S} : span_norm R I = ⊥ ↔ I = ⊥
begin simp only [span_norm, ideal.span_eq_bot, set.mem_image, set_like.mem_coe, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂, algebra.norm_eq_zero_iff_of_basis (module.free.choose_basis R S), @eq_bot_iff _ _ _ I, set_like.le_def], refl end
lemma
ideal.span_norm_eq_bot_iff
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm_eq_zero_iff_of_basis", "and_imp", "eq_bot_iff", "forall_apply_eq_imp_iff₂", "forall_exists_index", "ideal", "ideal.span_eq_bot", "is_domain", "module.finite", "module.free", "module.free.choose_basis", "set.mem_image", "set_like.le_def", "set_like.mem_coe" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
norm_mem_span_norm {I : ideal S} (x : S) (hx : x ∈ I) : algebra.norm R x ∈ I.span_norm R
subset_span (set.mem_image_of_mem _ hx)
lemma
ideal.norm_mem_span_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm", "ideal", "set.mem_image_of_mem" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_singleton {r : S} : span_norm R (span ({r} : set S)) = span {algebra.norm R r}
le_antisymm (span_le.mpr (λ x hx, mem_span_singleton.mpr begin obtain ⟨x, hx', rfl⟩ := (set.mem_image _ _ _).mp hx, exact map_dvd _ (mem_span_singleton.mp hx') end)) ((span_singleton_le_iff_mem _).mpr (norm_mem_span_norm _ _ (mem_span_singleton_self _)))
lemma
ideal.span_norm_singleton
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm", "map_dvd", "set.mem_image" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_top : span_norm R (⊤ : ideal S) = ⊤
by simp [← ideal.span_singleton_one]
lemma
ideal.span_norm_top
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "ideal.span_singleton_one" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_span_norm (I : ideal S) {T : Type*} [comm_ring T] (f : R →+* T) : map f (span_norm R I) = span ((f ∘ algebra.norm R) '' (I : set S))
by rw [span_norm, map_span, set.image_image]
lemma
ideal.map_span_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm", "comm_ring", "ideal", "set.image_image" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_mono {I J : ideal S} (h : I ≤ J) : span_norm R I ≤ span_norm R J
ideal.span_mono (set.monotone_image h)
lemma
ideal.span_norm_mono
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "ideal.span_mono", "set.monotone_image" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_localization (I : ideal S) [module.finite R S] [module.free R S] (M : submonoid R) {Rₘ : Type*} (Sₘ : Type*) [comm_ring Rₘ] [algebra R Rₘ] [comm_ring Sₘ] [algebra S Sₘ] [algebra Rₘ Sₘ] [algebra R Sₘ] [is_scalar_tower R Rₘ Sₘ] [is_scalar_tower R S Sₘ] [is_localization M Rₘ] [is_localization (algebra.al...
begin casesI h : subsingleton_or_nontrivial R, { haveI := is_localization.unique R Rₘ M, simp }, let b := module.free.choose_basis R S, rw map_span_norm, refine span_eq_span (set.image_subset_iff.mpr _) (set.image_subset_iff.mpr _), { rintros a' ha', simp only [set.mem_preimage, submodule_span_eq, ←...
lemma
ideal.span_norm_localization
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra", "algebra.algebra_map_submonoid", "algebra.norm", "algebra.norm_algebra_map_of_basis", "algebra.norm_localization", "algebra_map", "comm_ring", "fintype.card", "ideal", "is_localization", "is_localization.mem_map_algebra_map_iff", "is_localization.unique", "is_scalar_tower", "is_...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_mul_span_norm_le (I J : ideal S) : span_norm R I * span_norm R J ≤ span_norm R (I * J)
begin rw [span_norm, span_norm, span_norm, ideal.span_mul_span', ← set.image_mul], refine ideal.span_mono (set.monotone_image _), rintros _ ⟨x, y, hxI, hyJ, rfl⟩, exact ideal.mul_mem_mul hxI hyJ end
lemma
ideal.span_norm_mul_span_norm_le
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "ideal.mul_mem_mul", "ideal.span_mono", "ideal.span_mul_span'", "set.image_mul", "set.monotone_image" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_mul_of_bot_or_top [is_domain R] [is_domain S] [module.free R S] [module.finite R S] (eq_bot_or_top : ∀ I : ideal R, I = ⊥ ∨ I = ⊤) (I J : ideal S) : span_norm R (I * J) = span_norm R I * span_norm R J
begin refine le_antisymm _ (span_norm_mul_span_norm_le _ _ _), cases eq_bot_or_top (span_norm R I) with hI hI, { rw [hI, span_norm_eq_bot_iff.mp hI, bot_mul, span_norm_bot], exact bot_le }, rw [hI, ideal.top_mul], cases eq_bot_or_top (span_norm R J) with hJ hJ, { rw [hJ, span_norm_eq_bot_iff.mp hJ, mul_...
lemma
ideal.span_norm_mul_of_bot_or_top
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "bot_le", "ideal", "ideal.top_mul", "is_domain", "le_top", "module.finite", "module.free" ]
This condition `eq_bot_or_top` is equivalent to being a field. However, `span_norm_mul_of_field` is harder to apply since we'd need to upgrade a `comm_ring R` instance to a `field R` instance.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_mul_of_field {K : Type*} [field K] [algebra K S] [is_domain S] [module.finite K S] (I J : ideal S) : span_norm K (I * J) = span_norm K I * span_norm K J
span_norm_mul_of_bot_or_top K eq_bot_or_top I J
lemma
ideal.span_norm_mul_of_field
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra", "field", "ideal", "is_domain", "module.finite" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_mul (I J : ideal S) : span_norm R (I * J) = span_norm R I * span_norm R J
begin nontriviality R, casesI subsingleton_or_nontrivial S, { have : ∀ I : ideal S, I = ⊤ := λ I, subsingleton.elim I ⊤, simp [this I, this J, this (I * J)] }, refine eq_of_localization_maximal _, unfreezingI { intros P hP }, by_cases hP0 : P = ⊥, { unfreezingI { subst hP0 }, rw span_norm_mul_of_b...
lemma
ideal.span_norm_mul
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra", "algebra.algebra_map_submonoid", "bot_le", "classical.dec_eq", "ideal", "ideal.map_mul", "is_dedekind_domain", "is_dedekind_domain.is_principal_ideal_ring_localization_over_prime", "is_domain", "is_localization.is_dedekind_domain", "is_localization.is_domain_localization", "is_local...
Multiplicativity of `ideal.span_norm`. simp-normal form is `map_mul (ideal.rel_norm R)`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_norm : ideal S →*₀ ideal R
{ to_fun := span_norm R, map_zero' := span_norm_bot R, map_one' := by rw [one_eq_top, span_norm_top R, one_eq_top], map_mul' := span_norm_mul R }
def
ideal.rel_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal" ]
The relative norm `ideal.rel_norm R (I : ideal S)`, where `R` and `S` are Dedekind domains, and `S` is an extension of `R` that is finite and free as a module.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_norm_apply (I : ideal S) : rel_norm R I = span (algebra.norm R '' (I : set S) : set R)
rfl
lemma
ideal.rel_norm_apply
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm", "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
span_norm_eq (I : ideal S) : span_norm R I = rel_norm R I
rfl
lemma
ideal.span_norm_eq
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_norm_bot : rel_norm R (⊥ : ideal S) = ⊥
by simpa only [zero_eq_bot] using map_zero (rel_norm R : ideal S →*₀ _)
lemma
ideal.rel_norm_bot
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_norm_top : rel_norm R (⊤ : ideal S) = ⊤
by simpa only [one_eq_top] using map_one (rel_norm R : ideal S →*₀ _)
lemma
ideal.rel_norm_top
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal", "map_one" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_norm_eq_bot_iff {I : ideal S} : rel_norm R I = ⊥ ↔ I = ⊥
span_norm_eq_bot_iff
lemma
ideal.rel_norm_eq_bot_iff
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
norm_mem_rel_norm (I : ideal S) {x : S} (hx : x ∈ I) : algebra.norm R x ∈ rel_norm R I
norm_mem_span_norm R x hx
lemma
ideal.norm_mem_rel_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm", "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_norm_singleton (r : S) : rel_norm R (span ({r} : set S)) = span {algebra.norm R r}
span_norm_singleton R
lemma
ideal.rel_norm_singleton
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_rel_norm (I : ideal S) {T : Type*} [comm_ring T] (f : R →+* T) : map f (rel_norm R I) = span ((f ∘ algebra.norm R) '' (I : set S))
map_span_norm R I f
lemma
ideal.map_rel_norm
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "algebra.norm", "comm_ring", "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_norm_mono {I J : ideal S} (h : I ≤ J) : rel_norm R I ≤ rel_norm R J
span_norm_mono R h
lemma
ideal.rel_norm_mono
ring_theory.ideal
src/ring_theory/ideal/norm.lean
[ "algebra.char_p.quotient", "data.finsupp.fintype", "data.int.absolute_value", "data.int.associated", "linear_algebra.free_module.determinant", "linear_algebra.free_module.ideal_quotient", "ring_theory.dedekind_domain.pid", "ring_theory.local_properties", "ring_theory.localization.norm" ]
[ "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_smul' : has_smul (ideal R) (submodule R M)
⟨submodule.map₂ (linear_map.lsmul R M)⟩
instance
submodule.has_smul'
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "has_smul", "ideal", "linear_map.lsmul", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.ideal.smul_eq_mul (I J : ideal R) : I • J = I * J
rfl
lemma
ideal.smul_eq_mul
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "ideal" ]
This duplicates the global `smul_eq_mul`, but doesn't have to unfold anywhere near as much to apply.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
annihilator (N : submodule R M) : ideal R
(linear_map.lsmul R N).ker
def
submodule.annihilator
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "ideal", "linear_map.lsmul", "submodule" ]
`N.annihilator` is the ideal of all elements `r : R` such that `r • N = 0`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_annihilator {r} : r ∈ N.annihilator ↔ ∀ n ∈ N, r • n = (0:M)
⟨λ hr n hn, congr_arg subtype.val (linear_map.ext_iff.1 (linear_map.mem_ker.1 hr) ⟨n, hn⟩), λ h, linear_map.mem_ker.2 $ linear_map.ext $ λ n, subtype.eq $ h n.1 n.2⟩
theorem
submodule.mem_annihilator
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "linear_map.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_annihilator' {r} : r ∈ N.annihilator ↔ N ≤ comap (r • (linear_map.id : M →ₗ[R] M)) ⊥
mem_annihilator.trans ⟨λ H n hn, (mem_bot R).2 $ H n hn, λ H n hn, (mem_bot R).1 $ H hn⟩
theorem
submodule.mem_annihilator'
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "linear_map.id" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_annihilator_span (s : set M) (r : R) : r ∈ (submodule.span R s).annihilator ↔ ∀ n : s, r • (n : M) = 0
begin rw submodule.mem_annihilator, split, { intros h n, exact h _ (submodule.subset_span n.prop) }, { intros h n hn, apply submodule.span_induction hn, { intros x hx, exact h ⟨x, hx⟩ }, { exact smul_zero _ }, { intros x y hx hy, rw [smul_add, hx, hy, zero_add] }, { intros a x hx, rw [smul_c...
lemma
submodule.mem_annihilator_span
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "smul_add", "smul_zero", "submodule.mem_annihilator", "submodule.span", "submodule.span_induction", "submodule.subset_span" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_annihilator_span_singleton (g : M) (r : R) : r ∈ (submodule.span R ({g} : set M)).annihilator ↔ r • g = 0
by simp [mem_annihilator_span]
lemma
submodule.mem_annihilator_span_singleton
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "submodule.span" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
annihilator_bot : (⊥ : submodule R M).annihilator = ⊤
(ideal.eq_top_iff_one _).2 $ mem_annihilator'.2 bot_le
theorem
submodule.annihilator_bot
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "bot_le", "ideal.eq_top_iff_one", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
annihilator_eq_top_iff : N.annihilator = ⊤ ↔ N = ⊥
⟨λ H, eq_bot_iff.2 $ λ (n:M) hn, (mem_bot R).2 $ one_smul R n ▸ mem_annihilator.1 ((ideal.eq_top_iff_one _).1 H) n hn, λ H, H.symm ▸ annihilator_bot⟩
theorem
submodule.annihilator_eq_top_iff
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "ideal.eq_top_iff_one", "one_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
annihilator_mono (h : N ≤ P) : P.annihilator ≤ N.annihilator
λ r hrp, mem_annihilator.2 $ λ n hn, mem_annihilator.1 hrp n $ h hn
theorem
submodule.annihilator_mono
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
annihilator_supr (ι : Sort w) (f : ι → submodule R M) : (annihilator ⨆ i, f i) = ⨅ i, annihilator (f i)
le_antisymm (le_infi $ λ i, annihilator_mono $ le_supr _ _) (λ r H, mem_annihilator'.2 $ supr_le $ λ i, have _ := (mem_infi _).1 H i, mem_annihilator'.1 this)
theorem
submodule.annihilator_supr
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "le_infi", "le_supr", "submodule", "supr_le" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_mem_smul {r} {n} (hr : r ∈ I) (hn : n ∈ N) : r • n ∈ I • N
apply_mem_map₂ _ hr hn
theorem
submodule.smul_mem_smul
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_le {P : submodule R M} : I • N ≤ P ↔ ∀ (r ∈ I) (n ∈ N), r • n ∈ P
map₂_le
theorem
submodule.smul_le
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_induction_on {p : M → Prop} {x} (H : x ∈ I • N) (Hb : ∀ (r ∈ I) (n ∈ N), p (r • n)) (H1 : ∀ x y, p x → p y → p (x + y)) : p x
begin have H0 : p 0 := by simpa only [zero_smul] using Hb 0 I.zero_mem 0 N.zero_mem, refine submodule.supr_induction _ H _ H0 H1, rintros ⟨i, hi⟩ m ⟨j, hj, (rfl : i • _ = m) ⟩, exact Hb _ hi _ hj, end
theorem
submodule.smul_induction_on
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "submodule.supr_induction", "zero_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_induction_on' {x : M} (hx : x ∈ I • N) {p : Π x, x ∈ I • N → Prop} (Hb : ∀ (r : R) (hr : r ∈ I) (n : M) (hn : n ∈ N), p (r • n) (smul_mem_smul hr hn)) (H1 : ∀ x hx y hy, p x hx → p y hy → p (x + y) (submodule.add_mem _ ‹_› ‹_›)) : p x hx
begin refine exists.elim _ (λ (h : x ∈ I • N) (H : p x h), H), exact smul_induction_on hx (λ a ha x hx, ⟨_, Hb _ ha _ hx⟩) (λ x y ⟨_, hx⟩ ⟨_, hy⟩, ⟨_, H1 _ _ _ _ hx hy⟩), end
theorem
submodule.smul_induction_on'
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "submodule.add_mem" ]
Dependent version of `submodule.smul_induction_on`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_smul_span_singleton {I : ideal R} {m : M} {x : M} : x ∈ I • span R ({m} : set M) ↔ ∃ y ∈ I, y • m = x
⟨λ hx, smul_induction_on hx (λ r hri n hnm, let ⟨s, hs⟩ := mem_span_singleton.1 hnm in ⟨r * s, I.mul_mem_right _ hri, hs ▸ mul_smul r s m⟩) (λ m1 m2 ⟨y1, hyi1, hy1⟩ ⟨y2, hyi2, hy2⟩, ⟨y1 + y2, I.add_mem hyi1 hyi2, by rw [add_smul, hy1, hy2]⟩), λ ⟨y, hyi, hy⟩, hy ▸ smul_mem_smul hyi (subset_span $ set.mem_sin...
theorem
submodule.mem_smul_span_singleton
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "add_smul", "ideal", "set.mem_singleton" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_le_right : I • N ≤ N
smul_le.2 $ λ r hr n, N.smul_mem r
theorem
submodule.smul_le_right
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_mono (hij : I ≤ J) (hnp : N ≤ P) : I • N ≤ J • P
map₂_le_map₂ hij hnp
theorem
submodule.smul_mono
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_mono_left (h : I ≤ J) : I • N ≤ J • N
map₂_le_map₂_left h
theorem
submodule.smul_mono_left
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_mono_right (h : N ≤ P) : I • N ≤ I • P
map₂_le_map₂_right h
theorem
submodule.smul_mono_right
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_le_smul_top (I : ideal R) (f : R →ₗ[R] M) : submodule.map f I ≤ I • (⊤ : submodule R M)
begin rintros _ ⟨y, hy, rfl⟩, rw [← mul_one y, ← smul_eq_mul, f.map_smul], exact smul_mem_smul hy mem_top end
lemma
submodule.map_le_smul_top
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "ideal", "mul_one", "smul_eq_mul", "submodule", "submodule.map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
annihilator_smul (N : submodule R M) : annihilator N • N = ⊥
eq_bot_iff.2 (smul_le.2 (λ r, mem_annihilator.1))
theorem
submodule.annihilator_smul
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
annihilator_mul (I : ideal R) : annihilator I * I = ⊥
annihilator_smul I
theorem
submodule.annihilator_mul
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_annihilator (I : ideal R) : I * annihilator I = ⊥
by rw [mul_comm, annihilator_mul]
theorem
submodule.mul_annihilator
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "ideal", "mul_comm" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_bot : I • (⊥ : submodule R M) = ⊥
map₂_bot_right _ _
theorem
submodule.smul_bot
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
bot_smul : (⊥ : ideal R) • N = ⊥
map₂_bot_left _ _
theorem
submodule.bot_smul
ring_theory.ideal
src/ring_theory/ideal/operations.lean
[ "algebra.algebra.operations", "algebra.ring.equiv", "data.nat.choose.sum", "linear_algebra.basis.bilinear", "ring_theory.coprime.lemmas", "ring_theory.ideal.basic", "ring_theory.non_zero_divisors" ]
[ "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83