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smul_coe_torsion_by (x : torsion_by R M a) : a • (x : M) = 0
x.prop
lemma
submodule.smul_coe_torsion_by
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_torsion_by_iff (x : M) : x ∈ torsion_by R M a ↔ a • x = 0
iff.rfl
lemma
submodule.mem_torsion_by_iff
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_torsion_by_set_iff (x : M) : x ∈ torsion_by_set R M s ↔ ∀ a : s, (a : R) • x = 0
begin refine ⟨λ h ⟨a, ha⟩, mem_Inf.mp h _ (set.mem_image_of_mem _ ha), λ h, mem_Inf.mpr _⟩, rintro _ ⟨a, ha, rfl⟩, exact h ⟨a, ha⟩ end
lemma
submodule.mem_torsion_by_set_iff
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "set.mem_image_of_mem" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_singleton_eq : torsion_by_set R M {a} = torsion_by R M a
begin ext x, simp only [mem_torsion_by_set_iff, set_coe.forall, subtype.coe_mk, set.mem_singleton_iff, forall_eq, mem_torsion_by_iff] end
lemma
submodule.torsion_by_singleton_eq
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "forall_eq", "set.mem_singleton_iff", "set_coe.forall", "subtype.coe_mk" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_set_le_torsion_by_set_of_subset {s t : set R} (st : s ⊆ t) : torsion_by_set R M t ≤ torsion_by_set R M s
Inf_le_Inf $ λ _ ⟨a, ha, h⟩, ⟨a, st ha, h⟩
lemma
submodule.torsion_by_set_le_torsion_by_set_of_subset
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "Inf_le_Inf" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_set_eq_torsion_by_span : torsion_by_set R M s = torsion_by_set R M (ideal.span s)
begin refine le_antisymm (λ x hx, _) (torsion_by_set_le_torsion_by_set_of_subset subset_span), rw mem_torsion_by_set_iff at hx ⊢, suffices : ideal.span s ≤ ideal.torsion_of R M x, { rintro ⟨a, ha⟩, exact this ha }, rw ideal.span_le, exact λ a ha, hx ⟨a, ha⟩ end
lemma
submodule.torsion_by_set_eq_torsion_by_span
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "ideal.span", "ideal.span_le", "ideal.torsion_of" ]
Torsion by a set is torsion by the ideal generated by it.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_span_singleton_eq : torsion_by_set R M (R ∙ a) = torsion_by R M a
((torsion_by_set_eq_torsion_by_span _).symm.trans $ torsion_by_singleton_eq _)
lemma
submodule.torsion_by_span_singleton_eq
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_le_torsion_by_of_dvd (a b : R) (dvd : a ∣ b) : torsion_by R M a ≤ torsion_by R M b
begin rw [← torsion_by_span_singleton_eq, ← torsion_by_singleton_eq], apply torsion_by_set_le_torsion_by_set_of_subset, rintro c (rfl : c = b), exact ideal.mem_span_singleton.mpr dvd end
lemma
submodule.torsion_by_le_torsion_by_of_dvd
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_one : torsion_by R M 1 = ⊥
eq_bot_iff.mpr (λ _ h, by { rw [mem_torsion_by_iff, one_smul] at h, exact h })
lemma
submodule.torsion_by_one
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "one_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_univ : torsion_by_set R M set.univ = ⊥
by { rw [eq_bot_iff, ← torsion_by_one, ← torsion_by_singleton_eq], exact torsion_by_set_le_torsion_by_set_of_subset (λ _ _, trivial) }
lemma
submodule.torsion_by_univ
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "eq_bot_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_singleton_iff : is_torsion_by_set R M {a} ↔ is_torsion_by R M a
begin refine ⟨λ h x, @h _ ⟨_, set.mem_singleton _⟩, λ h x, _⟩, rintro ⟨b, rfl : b = a⟩, exact @h _ end
lemma
module.is_torsion_by_singleton_iff
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "set.mem_singleton" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_set_iff_torsion_by_set_eq_top : is_torsion_by_set R M s ↔ submodule.torsion_by_set R M s = ⊤
⟨λ h, eq_top_iff.mpr (λ _ _, (mem_torsion_by_set_iff _ _).mpr $ @h _), λ h x, by { rw [← mem_torsion_by_set_iff, h], trivial }⟩
lemma
module.is_torsion_by_set_iff_torsion_by_set_eq_top
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "submodule.torsion_by_set" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_iff_torsion_by_eq_top : is_torsion_by R M a ↔ torsion_by R M a = ⊤
by rw [← torsion_by_singleton_eq, ← is_torsion_by_singleton_iff, is_torsion_by_set_iff_torsion_by_set_eq_top]
lemma
module.is_torsion_by_iff_torsion_by_eq_top
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
A `a`-torsion module is a module whose `a`-torsion submodule is the full space.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_set_iff_is_torsion_by_span : is_torsion_by_set R M s ↔ is_torsion_by_set R M (ideal.span s)
by rw [is_torsion_by_set_iff_torsion_by_set_eq_top, is_torsion_by_set_iff_torsion_by_set_eq_top, torsion_by_set_eq_torsion_by_span]
lemma
module.is_torsion_by_set_iff_is_torsion_by_span
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "ideal.span" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_span_singleton_iff : is_torsion_by_set R M (R ∙ a) ↔ is_torsion_by R M a
((is_torsion_by_set_iff_is_torsion_by_span _).symm.trans $ is_torsion_by_singleton_iff _)
lemma
module.is_torsion_by_span_singleton_iff
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_set_is_torsion_by_set : is_torsion_by_set R (torsion_by_set R M s) s
λ ⟨x, hx⟩ a, subtype.ext $ (mem_torsion_by_set_iff _ _).mp hx a
lemma
submodule.torsion_by_set_is_torsion_by_set
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "subtype.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_is_torsion_by : is_torsion_by R (torsion_by R M a) a
λ _, smul_torsion_by _ _
lemma
submodule.torsion_by_is_torsion_by
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
The `a`-torsion submodule is a `a`-torsion module.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_torsion_by_eq_top : torsion_by R (torsion_by R M a) a = ⊤
(is_torsion_by_iff_torsion_by_eq_top a).mp $ torsion_by_is_torsion_by a
lemma
submodule.torsion_by_torsion_by_eq_top
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_set_torsion_by_set_eq_top : torsion_by_set R (torsion_by_set R M s) s = ⊤
(is_torsion_by_set_iff_torsion_by_set_eq_top s).mp $ torsion_by_set_is_torsion_by_set s
lemma
submodule.torsion_by_set_torsion_by_set_eq_top
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_gc : @galois_connection (submodule R M) (ideal R)ᵒᵈ _ _ annihilator (λ I, torsion_by_set R M $ I.of_dual)
λ A I, ⟨λ h x hx, (mem_torsion_by_set_iff _ _).mpr $ λ ⟨a, ha⟩, mem_annihilator.mp (h ha) x hx, λ h a ha, mem_annihilator.mpr $ λ x hx, (mem_torsion_by_set_iff _ _).mp (h hx) ⟨a, ha⟩⟩
lemma
submodule.torsion_gc
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "galois_connection", "ideal", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
supr_torsion_by_ideal_eq_torsion_by_infi : (⨆ i ∈ S, torsion_by_set R M $ p i) = torsion_by_set R M ↑(⨅ i ∈ S, p i)
begin cases S.eq_empty_or_nonempty with h h, { rw h, convert supr_emptyset, convert torsion_by_univ, convert top_coe, exact infi_emptyset }, apply le_antisymm, { apply supr_le _, intro i, apply supr_le _, intro is, apply torsion_by_set_le_torsion_by_set_of_subset, exact (infi_le (λ i, ⨅ (H : i ∈ S), p i...
lemma
submodule.supr_torsion_by_ideal_eq_torsion_by_infi
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "finset.sum_smul", "ideal.eq_top_iff_one", "ideal.mul_mem_left", "ideal.mul_mem_right", "ideal.supr_infi_eq_top_iff_pairwise", "infi_emptyset", "infi_le", "one_smul", "smul_smul", "supr_emptyset", "supr_le" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sup_indep_torsion_by_ideal : S.sup_indep (λ i, torsion_by_set R M $ p i)
λ T hT i hi hiT, begin rw [disjoint_iff, finset.sup_eq_supr, supr_torsion_by_ideal_eq_torsion_by_infi $ λ i hi j hj ij, hp (hT hi) (hT hj) ij], have := @galois_connection.u_inf _ _ (order_dual.to_dual _) (order_dual.to_dual _) _ _ _ _ (torsion_gc R M), dsimp at this ⊢, rw [← this, ideal.sup_infi_eq_top, t...
lemma
submodule.sup_indep_torsion_by_ideal
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "disjoint_iff", "finset.sup_eq_supr", "galois_connection.u_inf", "ideal.sup_infi_eq_top", "order_dual.to_dual" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
supr_torsion_by_eq_torsion_by_prod : (⨆ i ∈ S, torsion_by R M $ q i) = torsion_by R M (∏ i in S, q i)
begin rw [← torsion_by_span_singleton_eq, ideal.submodule_span_eq, ← ideal.finset_inf_span_singleton _ _ hq, finset.inf_eq_infi, ← supr_torsion_by_ideal_eq_torsion_by_infi], { congr, ext : 1, congr, ext : 1, exact (torsion_by_span_singleton_eq _).symm }, { exact λ i hi j hj ij, (ideal.sup_eq_top_iff_is_co...
lemma
submodule.supr_torsion_by_eq_torsion_by_prod
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "finset.inf_eq_infi", "ideal.finset_inf_span_singleton", "ideal.submodule_span_eq", "ideal.sup_eq_top_iff_is_coprime" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sup_indep_torsion_by : S.sup_indep (λ i, torsion_by R M $ q i)
begin convert sup_indep_torsion_by_ideal (λ i hi j hj ij, (ideal.sup_eq_top_iff_is_coprime (q i) _).mpr $ hq hi hj ij), ext : 1, exact (torsion_by_span_singleton_eq _).symm, end
lemma
submodule.sup_indep_torsion_by
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "ideal.sup_eq_top_iff_is_coprime" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_set_is_internal {p : ι → ideal R} (hp : (S : set ι).pairwise $ λ i j, p i ⊔ p j = ⊤) (hM : module.is_torsion_by_set R M (⨅ i ∈ S, p i : ideal R)) : direct_sum.is_internal (λ i : S, torsion_by_set R M $ p i)
direct_sum.is_internal_submodule_of_independent_of_supr_eq_top (complete_lattice.independent_iff_sup_indep.mpr $ sup_indep_torsion_by_ideal hp) ((supr_subtype'' ↑S $ λ i, torsion_by_set R M $ p i).trans $ (supr_torsion_by_ideal_eq_torsion_by_infi hp).trans $ (module.is_torsion_by_set_iff_torsion_by_set_eq_t...
lemma
submodule.torsion_by_set_is_internal
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "direct_sum.is_internal", "direct_sum.is_internal_submodule_of_independent_of_supr_eq_top", "ideal", "module.is_torsion_by_set", "module.is_torsion_by_set_iff_torsion_by_set_eq_top", "pairwise", "supr_subtype''" ]
If the `p i` are pairwise coprime, a `⨅ i, p i`-torsion module is the internal direct sum of its `p i`-torsion submodules.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_is_internal {q : ι → R} (hq : (S : set ι).pairwise $ is_coprime on q) (hM : module.is_torsion_by R M $ ∏ i in S, q i) : direct_sum.is_internal (λ i : S, torsion_by R M $ q i)
begin rw [← module.is_torsion_by_span_singleton_iff, ideal.submodule_span_eq, ← ideal.finset_inf_span_singleton _ _ hq, finset.inf_eq_infi] at hM, convert torsion_by_set_is_internal (λ i hi j hj ij, (ideal.sup_eq_top_iff_is_coprime (q i) _).mpr $ hq hi hj ij) hM, ext : 1, exact (torsion_by_span_singleton_...
lemma
submodule.torsion_by_is_internal
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "direct_sum.is_internal", "finset.inf_eq_infi", "ideal.finset_inf_span_singleton", "ideal.submodule_span_eq", "ideal.sup_eq_top_iff_is_coprime", "is_coprime", "module.is_torsion_by", "module.is_torsion_by_span_singleton_iff", "pairwise" ]
If the `q i` are pairwise coprime, a `∏ i, q i`-torsion module is the internal direct sum of its `q i`-torsion submodules.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_set.has_smul : has_smul (R ⧸ I) M
{ smul := λ b x, quotient.lift_on' b (• x) $ λ b₁ b₂ h, begin show b₁ • x = b₂ • x, have : (-b₁ + b₂) • x = 0 := @hM x ⟨_, quotient_add_group.left_rel_apply.mp h⟩, rw [add_smul, neg_smul, neg_add_eq_zero] at this, exact this end }
def
module.is_torsion_by_set.has_smul
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "add_smul", "has_smul", "neg_smul", "quotient.lift_on'" ]
can't be an instance because hM can't be inferred
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_set.mk_smul (b : R) (x : M) : by haveI
hM.has_smul; exact ideal.quotient.mk I b • x = b • x := rfl
lemma
module.is_torsion_by_set.mk_smul
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "ideal.quotient.mk" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_set.module : module (R ⧸ I) M
@function.surjective.module_left _ _ _ _ _ _ _ hM.has_smul _ ideal.quotient.mk_surjective (is_torsion_by_set.mk_smul hM)
def
module.is_torsion_by_set.module
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "function.surjective.module_left", "ideal.quotient.mk_surjective", "module" ]
A `(R ⧸ I)`-module is a `R`-module which `is_torsion_by_set R M I`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_by_set.is_scalar_tower {S : Type*} [has_smul S R] [has_smul S M] [is_scalar_tower S R M] [is_scalar_tower S R R] : @@is_scalar_tower S (R ⧸ I) M _ (is_torsion_by_set.module hM).to_has_smul _
{ smul_assoc := λ b d x, quotient.induction_on' d $ λ c, (smul_assoc b c x : _) }
instance
module.is_torsion_by_set.is_scalar_tower
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "has_smul", "is_scalar_tower", "quotient.induction_on'", "smul_assoc" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_set.mk_smul (I : ideal R) (b : R) (x : torsion_by_set R M I) : ideal.quotient.mk I b • x = b • x
rfl
lemma
submodule.torsion_by_set.mk_smul
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "ideal", "ideal.quotient.mk" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by.mk_smul (a b : R) (x : torsion_by R M a) : ideal.quotient.mk (R ∙ a) b • x = b • x
rfl
lemma
submodule.torsion_by.mk_smul
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "ideal.quotient.mk" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_torsion'_iff (x : M) : x ∈ torsion' R M S ↔ ∃ a : S, a • x = 0
iff.rfl
lemma
submodule.mem_torsion'_iff
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_torsion_iff (x : M) : x ∈ torsion R M ↔ ∃ a : R⁰, a • x = 0
iff.rfl
lemma
submodule.mem_torsion_iff
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion'_iff_torsion'_eq_top : is_torsion' M S ↔ torsion' R M S = ⊤
⟨λ h, eq_top_iff.mpr (λ _ _, @h _), λ h x, by { rw [← @mem_torsion'_iff R, h], trivial }⟩
lemma
submodule.is_torsion'_iff_torsion'_eq_top
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
A `S`-torsion module is a module whose `S`-torsion submodule is the full space.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion'_is_torsion' : is_torsion' (torsion' R M S) S
λ ⟨x, ⟨a, h⟩⟩, ⟨a, subtype.ext h⟩
lemma
submodule.torsion'_is_torsion'
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "subtype.ext" ]
The `S`-torsion submodule is a `S`-torsion module.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion'_torsion'_eq_top : torsion' R (torsion' R M S) S = ⊤
(is_torsion'_iff_torsion'_eq_top S).mp $ torsion'_is_torsion' S
lemma
submodule.torsion'_torsion'_eq_top
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_torsion_eq_top : torsion R (torsion R M) = ⊤
torsion'_torsion'_eq_top R⁰
lemma
submodule.torsion_torsion_eq_top
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[]
The torsion submodule of the torsion submodule (viewed as a module) is the full torsion module.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_is_torsion : module.is_torsion R (torsion R M)
torsion'_is_torsion' R⁰
lemma
submodule.torsion_is_torsion
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "module.is_torsion" ]
The torsion submodule is always a torsion module.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.module.is_torsion_by_set_annihilator_top : module.is_torsion_by_set R M (⊤ : submodule R M).annihilator
λ x ha, mem_annihilator.mp ha.prop x mem_top
lemma
module.is_torsion_by_set_annihilator_top
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "module.is_torsion_by_set", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.submodule.annihilator_top_inter_non_zero_divisors [module.finite R M] (hM : module.is_torsion R M) : ((⊤ : submodule R M).annihilator : set R) ∩ R⁰ ≠ ∅
begin obtain ⟨S, hS⟩ := ‹module.finite R M›.out, refine set.nonempty.ne_empty ⟨_, _, (∏ x in S, (@hM x).some : R⁰).prop⟩, rw [submonoid.coe_finset_prod, set_like.mem_coe, ←hS, mem_annihilator_span], intro n, letI := classical.dec_eq M, rw [←finset.prod_erase_mul _ _ n.prop, mul_smul, ←submonoid.smul_def, (@...
lemma
submodule.annihilator_top_inter_non_zero_divisors
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "classical.dec_eq", "module.finite", "module.is_torsion", "set_like.mem_coe", "smul_zero", "submodule", "submonoid.coe_finset_prod" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_torsion_eq_annihilator_ne_bot : (torsion R M : set M) = { x : M | (R ∙ x).annihilator ≠ ⊥ }
begin ext x, simp_rw [submodule.ne_bot_iff, mem_annihilator, mem_span_singleton], exact ⟨λ ⟨a, hax⟩, ⟨a, λ _ ⟨b, hb⟩, by rw [← hb, smul_comm, ← submonoid.smul_def, hax, smul_zero], non_zero_divisors.coe_ne_zero _⟩, λ ⟨a, hax, ha⟩, ⟨⟨_, mem_non_zero_divisors_of_ne_zero ha⟩, hax x ⟨1, one_smul _ _⟩⟩⟩ end
lemma
submodule.coe_torsion_eq_annihilator_ne_bot
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "mem_non_zero_divisors_of_ne_zero", "non_zero_divisors.coe_ne_zero", "one_smul", "smul_zero", "submodule.ne_bot_iff", "submonoid.smul_def" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
no_zero_smul_divisors_iff_torsion_eq_bot : no_zero_smul_divisors R M ↔ torsion R M = ⊥
begin split; intro h, { haveI : no_zero_smul_divisors R M := h, rw eq_bot_iff, rintro x ⟨a, hax⟩, change (a : R) • x = 0 at hax, cases eq_zero_or_eq_zero_of_smul_eq_zero hax with h0 h0, { exfalso, exact non_zero_divisors.coe_ne_zero a h0 }, { exact h0 } }, { exact { eq_zero_or_eq_zero_of_smul_eq_z...
lemma
submodule.no_zero_smul_divisors_iff_torsion_eq_bot
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "eq_bot_iff", "mem_non_zero_divisors_of_ne_zero", "no_zero_smul_divisors", "non_zero_divisors.coe_ne_zero" ]
A module over a domain has `no_zero_smul_divisors` iff its torsion submodule is trivial.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_eq_bot : torsion R (M ⧸ torsion R M) = ⊥
eq_bot_iff.mpr $ λ z, quotient.induction_on' z $ λ x ⟨a, hax⟩, begin rw [quotient.mk'_eq_mk, ← quotient.mk_smul, quotient.mk_eq_zero] at hax, rw [mem_bot, quotient.mk'_eq_mk, quotient.mk_eq_zero], cases hax with b h, exact ⟨b * a, (mul_smul _ _ _).trans h⟩ end
lemma
submodule.quotient_torsion.torsion_eq_bot
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "quotient.induction_on'", "quotient.mk'_eq_mk" ]
Quotienting by the torsion submodule gives a torsion-free module.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
no_zero_smul_divisors [is_domain R] : no_zero_smul_divisors R (M ⧸ torsion R M)
no_zero_smul_divisors_iff_torsion_eq_bot.mpr torsion_eq_bot
instance
submodule.quotient_torsion.no_zero_smul_divisors
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "is_domain", "no_zero_smul_divisors" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion'_powers_iff (p : R) : is_torsion' M (submonoid.powers p) ↔ ∀ x : M, ∃ n : ℕ, p ^ n • x = 0
⟨λ h x, let ⟨⟨a, ⟨n, rfl⟩⟩, hx⟩ := @h x in ⟨n, hx⟩, λ h x, let ⟨n, hn⟩ := h x in ⟨⟨_, ⟨n, rfl⟩⟩, hn⟩⟩
lemma
submodule.is_torsion'_powers_iff
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "submonoid.powers" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
p_order {p : R} (hM : is_torsion' M $ submonoid.powers p) (x : M) [Π n : ℕ, decidable (p ^ n • x = 0)]
nat.find $ (is_torsion'_powers_iff p).mp hM x
def
submodule.p_order
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "submonoid.powers" ]
In a `p ^ ∞`-torsion module (that is, a module where all elements are cancelled by scalar multiplication by some power of `p`), the smallest `n` such that `p ^ n • x = 0`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
pow_p_order_smul {p : R} (hM : is_torsion' M $ submonoid.powers p) (x : M) [Π n : ℕ, decidable (p ^ n • x = 0)] : p ^ p_order hM x • x = 0
nat.find_spec $ (is_torsion'_powers_iff p).mp hM x
lemma
submodule.pow_p_order_smul
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "submonoid.powers" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exists_is_torsion_by {p : R} (hM : is_torsion' M $ submonoid.powers p) (d : ℕ) (hd : d ≠ 0) (s : fin d → M) (hs : span R (set.range s) = ⊤) : ∃ j : fin d, module.is_torsion_by R M (p ^ p_order hM (s j))
begin let oj := list.argmax (λ i, p_order hM $ s i) (list.fin_range d), have hoj : oj.is_some := (option.ne_none_iff_is_some.mp $ λ eq_none, hd $ list.fin_range_eq_nil.mp $ list.argmax_eq_none.mp eq_none), use option.get hoj, rw [is_torsion_by_iff_torsion_by_eq_top, eq_top_iff, ← hs, submodule.span_le, ...
lemma
submodule.exists_is_torsion_by
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "eq_top_iff", "list.argmax", "list.fin_range", "list.le_of_mem_argmax", "list.mem_fin_range", "module.is_torsion_by", "option.get_mem", "pow_add", "set.range", "set.range_subset_iff", "smul_zero", "submodule.span_le", "submonoid.powers" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
torsion_by_eq_span_singleton {R : Type*} [comm_ring R] (a b : R) (ha : a ∈ R⁰) : torsion_by R (R ⧸ R ∙ a * b) a = R ∙ (mk _ b)
begin ext x, rw [mem_torsion_by_iff, mem_span_singleton], obtain ⟨x, rfl⟩ := mk_surjective x, split; intro h, { rw [← mk_eq_mk, ← quotient.mk_smul, quotient.mk_eq_zero, mem_span_singleton] at h, obtain ⟨c, h⟩ := h, rw [smul_eq_mul, smul_eq_mul, mul_comm, mul_assoc, mul_cancel_left_mem_non_zero_divisor h...
lemma
ideal.quotient.torsion_by_eq_span_singleton
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "comm_ring", "mul_assoc", "mul_cancel_left_mem_non_zero_divisor", "mul_comm", "smul_eq_mul", "smul_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_iff_is_torsion_nat [add_comm_monoid M] : add_monoid.is_torsion M ↔ module.is_torsion ℕ M
begin refine ⟨λ h x, _, λ h x, _⟩, { obtain ⟨n, h0, hn⟩ := (is_of_fin_add_order_iff_nsmul_eq_zero x).mp (h x), exact ⟨⟨n, mem_non_zero_divisors_of_ne_zero $ ne_of_gt h0⟩, hn⟩ }, { rw is_of_fin_add_order_iff_nsmul_eq_zero, obtain ⟨n, hn⟩ := @h x, refine ⟨n, nat.pos_of_ne_zero (non_zero_divisors.coe_ne_...
theorem
add_monoid.is_torsion_iff_is_torsion_nat
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "add_comm_monoid", "mem_non_zero_divisors_of_ne_zero", "module.is_torsion", "non_zero_divisors.coe_ne_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_torsion_iff_is_torsion_int [add_comm_group M] : add_monoid.is_torsion M ↔ module.is_torsion ℤ M
begin refine ⟨λ h x, _, λ h x, _⟩, { obtain ⟨n, h0, hn⟩ := (is_of_fin_add_order_iff_nsmul_eq_zero x).mp (h x), exact ⟨⟨n, mem_non_zero_divisors_of_ne_zero $ ne_of_gt $ int.coe_nat_pos.mpr h0⟩, (coe_nat_zsmul _ _).trans hn⟩ }, { rw is_of_fin_add_order_iff_nsmul_eq_zero, obtain ⟨n, hn⟩ := @h x, ex...
theorem
add_monoid.is_torsion_iff_is_torsion_int
algebra.module
src/algebra/module/torsion.lean
[ "algebra.direct_sum.module", "algebra.module.big_operators", "linear_algebra.isomorphisms", "group_theory.torsion", "ring_theory.coprime.ideal", "ring_theory.finiteness" ]
[ "add_comm_group", "mem_non_zero_divisors_of_ne_zero", "module.is_torsion", "non_zero_divisors.coe_ne_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_smul_left [has_smul R M] : has_smul (ulift R) M
⟨λ s x, s.down • x⟩
instance
ulift.has_smul_left
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "has_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_def [has_smul R M] (s : ulift R) (x : M) : s • x = s.down • x
rfl
lemma
ulift.smul_def
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "has_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_scalar_tower [has_smul R M] [has_smul M N] [has_smul R N] [is_scalar_tower R M N] : is_scalar_tower (ulift R) M N
⟨λ x y z, show (x.down • y) • z = x.down • y • z, from smul_assoc _ _ _⟩
instance
ulift.is_scalar_tower
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "has_smul", "is_scalar_tower", "smul_assoc" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_scalar_tower' [has_smul R M] [has_smul M N] [has_smul R N] [is_scalar_tower R M N] : is_scalar_tower R (ulift M) N
⟨λ x y z, show (x • y.down) • z = x • y.down • z, from smul_assoc _ _ _⟩
instance
ulift.is_scalar_tower'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "has_smul", "is_scalar_tower", "smul_assoc" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_scalar_tower'' [has_smul R M] [has_smul M N] [has_smul R N] [is_scalar_tower R M N] : is_scalar_tower R M (ulift N)
⟨λ x y z, show up ((x • y) • z.down) = ⟨x • y • z.down⟩, by rw smul_assoc⟩
instance
ulift.is_scalar_tower''
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "has_smul", "is_scalar_tower" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_action [monoid R] [mul_action R M] : mul_action (ulift R) M
{ smul := (•), mul_smul := λ _ _, mul_smul _ _, one_smul := one_smul _ }
instance
ulift.mul_action
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "monoid", "mul_action", "one_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_action' [monoid R] [mul_action R M] : mul_action R (ulift M)
{ smul := (•), mul_smul := λ r s ⟨f⟩, ext _ _ $ mul_smul _ _ _, one_smul := λ ⟨f⟩, ext _ _ $ one_smul _ _ }
instance
ulift.mul_action'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "monoid", "mul_action", "one_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_zero_class [has_zero M] [smul_zero_class R M] : smul_zero_class (ulift R) M
{ smul_zero := λ _, smul_zero _, .. ulift.has_smul_left }
instance
ulift.smul_zero_class
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "smul_zero", "smul_zero_class", "ulift.has_smul_left" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_zero_class' [has_zero M] [smul_zero_class R M] : smul_zero_class R (ulift M)
{ smul_zero := λ c, by { ext, simp [smul_zero], } }
instance
ulift.smul_zero_class'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "smul_zero", "smul_zero_class" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
distrib_smul [add_zero_class M] [distrib_smul R M] : distrib_smul (ulift R) M
{ smul_add := λ _, smul_add _ }
instance
ulift.distrib_smul
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "add_zero_class", "distrib_smul", "smul_add" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
distrib_smul' [add_zero_class M] [distrib_smul R M] : distrib_smul R (ulift M)
{ smul_add := λ c f g, by { ext, simp [smul_add], } }
instance
ulift.distrib_smul'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "add_zero_class", "distrib_smul", "smul_add" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
distrib_mul_action [monoid R] [add_monoid M] [distrib_mul_action R M] : distrib_mul_action (ulift R) M
{ ..ulift.mul_action, ..ulift.distrib_smul }
instance
ulift.distrib_mul_action
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "add_monoid", "distrib_mul_action", "monoid", "ulift.distrib_smul", "ulift.mul_action" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
distrib_mul_action' [monoid R] [add_monoid M] [distrib_mul_action R M] : distrib_mul_action R (ulift M)
{ ..ulift.mul_action', ..ulift.distrib_smul' }
instance
ulift.distrib_mul_action'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "add_monoid", "distrib_mul_action", "monoid", "ulift.distrib_smul'", "ulift.mul_action'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_distrib_mul_action [monoid R] [monoid M] [mul_distrib_mul_action R M] : mul_distrib_mul_action (ulift R) M
{ smul_one := λ _, smul_one _, smul_mul := λ _, smul_mul' _ }
instance
ulift.mul_distrib_mul_action
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "monoid", "mul_distrib_mul_action", "smul_mul'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_distrib_mul_action' [monoid R] [monoid M] [mul_distrib_mul_action R M] : mul_distrib_mul_action R (ulift M)
{ smul_one := λ _, by { ext, simp [smul_one], }, smul_mul := λ c f g, by { ext, simp [smul_mul'], }, ..ulift.mul_action' }
instance
ulift.mul_distrib_mul_action'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "monoid", "mul_distrib_mul_action", "smul_mul'", "ulift.mul_action'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_with_zero [has_zero R] [has_zero M] [smul_with_zero R M] : smul_with_zero (ulift R) M
{ smul_zero := λ _, smul_zero _, zero_smul := zero_smul _, ..ulift.has_smul_left }
instance
ulift.smul_with_zero
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "smul_with_zero", "smul_zero", "ulift.has_smul_left", "zero_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_with_zero' [has_zero R] [has_zero M] [smul_with_zero R M] : smul_with_zero R (ulift M)
{ smul_zero := λ _, ulift.ext _ _ $ smul_zero _, zero_smul := λ _, ulift.ext _ _ $ zero_smul _ _ }
instance
ulift.smul_with_zero'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "smul_with_zero", "smul_zero", "zero_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_action_with_zero [monoid_with_zero R] [has_zero M] [mul_action_with_zero R M] : mul_action_with_zero (ulift R) M
{ ..ulift.smul_with_zero }
instance
ulift.mul_action_with_zero
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "monoid_with_zero", "mul_action_with_zero", "ulift.smul_with_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_action_with_zero' [monoid_with_zero R] [has_zero M] [mul_action_with_zero R M] : mul_action_with_zero R (ulift M)
{ ..ulift.smul_with_zero' }
instance
ulift.mul_action_with_zero'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "monoid_with_zero", "mul_action_with_zero", "ulift.smul_with_zero'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
module [semiring R] [add_comm_monoid M] [module R M] : module (ulift R) M
{ add_smul := λ _ _, add_smul _ _, ..ulift.smul_with_zero }
instance
ulift.module
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "add_comm_monoid", "add_smul", "module", "semiring", "ulift.smul_with_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
module' [semiring R] [add_comm_monoid M] [module R M] : module R (ulift M)
{ add_smul := λ _ _ _, ulift.ext _ _ $ add_smul _ _ _, ..ulift.smul_with_zero' }
instance
ulift.module'
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "add_comm_monoid", "add_smul", "module", "semiring", "ulift.smul_with_zero'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
module_equiv [semiring R] [add_comm_monoid M] [module R M] : ulift M ≃ₗ[R] M
{ to_fun := ulift.down, inv_fun := ulift.up, map_smul' := λ r x, rfl, map_add' := λ x y, rfl, left_inv := by tidy, right_inv := by tidy, }
def
ulift.module_equiv
algebra.module
src/algebra/module/ulift.lean
[ "algebra.ring.ulift", "algebra.module.equiv" ]
[ "add_comm_monoid", "inv_fun", "module", "semiring" ]
The `R`-linear equivalence between `ulift M` and `M`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fundamental_domain : set E
{ m | ∀ i, b.repr m i ∈ set.Ico (0 : K) 1 }
def
zspan.fundamental_domain
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "set.Ico" ]
The fundamental domain of the ℤ-lattice spanned by `b`. See `zspan.is_add_fundamental_domain` for the proof that it is the fundamental domain.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_fundamental_domain {m : E} : m ∈ fundamental_domain b ↔ ∀ i, b.repr m i ∈ set.Ico (0 : K) 1
iff.rfl
lemma
zspan.mem_fundamental_domain
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "set.Ico" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
floor (m : E) : span ℤ (set.range b)
∑ i, ⌊b.repr m i⌋ • b.restrict_scalars ℤ i
def
zspan.floor
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "set.range" ]
The map that sends a vector of `E` to the element of the ℤ-lattice spanned by `b` obtained by rounding down its coordinates on the basis `b`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ceil (m : E) : span ℤ (set.range b)
∑ i, ⌈b.repr m i⌉ • b.restrict_scalars ℤ i
def
zspan.ceil
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "set.range" ]
The map that sends a vector of `E` to the element of the ℤ-lattice spanned by `b` obtained by rounding up its coordinates on the basis `b`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
repr_floor_apply (m : E) (i : ι) : b.repr (floor b m) i = ⌊b.repr m i⌋
by { classical ; simp only [floor, zsmul_eq_smul_cast K, b.repr.map_smul, finsupp.single_apply, finset.sum_apply', basis.repr_self, finsupp.smul_single', mul_one, finset.sum_ite_eq', coe_sum, finset.mem_univ, if_true, coe_smul_of_tower, basis.restrict_scalars_apply, linear_equiv.map_sum] }
lemma
zspan.repr_floor_apply
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "basis.repr_self", "basis.restrict_scalars_apply", "finset.mem_univ", "finset.sum_apply'", "finsupp.single_apply", "finsupp.smul_single'", "linear_equiv.map_sum", "mul_one", "zsmul_eq_smul_cast" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
repr_ceil_apply (m : E) (i : ι) : b.repr (ceil b m) i = ⌈b.repr m i⌉
by { classical ; simp only [ceil, zsmul_eq_smul_cast K, b.repr.map_smul, finsupp.single_apply, finset.sum_apply', basis.repr_self, finsupp.smul_single', mul_one, finset.sum_ite_eq', coe_sum, finset.mem_univ, if_true, coe_smul_of_tower, basis.restrict_scalars_apply, linear_equiv.map_sum] }
lemma
zspan.repr_ceil_apply
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "basis.repr_self", "basis.restrict_scalars_apply", "finset.mem_univ", "finset.sum_apply'", "finsupp.single_apply", "finsupp.smul_single'", "linear_equiv.map_sum", "mul_one", "zsmul_eq_smul_cast" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
floor_eq_self_of_mem (m : E) (h : m ∈ span ℤ (set.range b)) : (floor b m : E) = m
begin apply b.ext_elem, simp_rw [repr_floor_apply b], intro i, obtain ⟨z, hz⟩ := (b.mem_span_iff_repr_mem ℤ _).mp h i, rw [← hz], exact congr_arg (coe : ℤ → K) (int.floor_int_cast z), end
lemma
zspan.floor_eq_self_of_mem
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "int.floor_int_cast", "set.range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ceil_eq_self_of_mem (m : E) (h : m ∈ span ℤ (set.range b)) : (ceil b m : E) = m
begin apply b.ext_elem, simp_rw [repr_ceil_apply b], intro i, obtain ⟨z, hz⟩ := (b.mem_span_iff_repr_mem ℤ _).mp h i, rw [← hz], exact congr_arg (coe : ℤ → K) (int.ceil_int_cast z), end
lemma
zspan.ceil_eq_self_of_mem
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "int.ceil_int_cast", "set.range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fract (m : E) : E
m - floor b m
def
zspan.fract
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[]
The map that sends a vector `E` to the fundamental domain of the lattice, see `zspan.fract_mem_fundamental_domain`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fract_apply (m : E) : fract b m = m - floor b m
rfl
lemma
zspan.fract_apply
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
repr_fract_apply (m : E) (i : ι): b.repr (fract b m) i = int.fract (b.repr m i)
by rw [fract, map_sub, finsupp.coe_sub, pi.sub_apply, repr_floor_apply, int.fract]
lemma
zspan.repr_fract_apply
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "finsupp.coe_sub", "int.fract" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fract_fract (m : E) : fract b (fract b m) = fract b m
basis.ext_elem b (λ _, by { classical ; simp only [repr_fract_apply, int.fract_fract] })
lemma
zspan.fract_fract
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "int.fract_fract" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fract_zspan_add (m : E) {v : E} (h : v ∈ span ℤ (set.range b)) : fract b (v + m) = fract b m
begin classical, refine (basis.ext_elem_iff b).mpr (λ i, _), simp_rw [repr_fract_apply, int.fract_eq_fract], use (b.restrict_scalars ℤ).repr ⟨v, h⟩ i, rw [map_add, finsupp.coe_add, pi.add_apply, add_tsub_cancel_right, ← (eq_int_cast (algebra_map ℤ K) _), basis.restrict_scalars_repr_apply, coe_mk], end
lemma
zspan.fract_zspan_add
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "add_tsub_cancel_right", "algebra_map", "basis.ext_elem_iff", "basis.restrict_scalars_repr_apply", "eq_int_cast", "finsupp.coe_add", "int.fract_eq_fract", "set.range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fract_add_zspan (m : E) {v : E} (h : v ∈ span ℤ (set.range b)) : fract b (m + v) = fract b m
by { rw [add_comm, fract_zspan_add b m h] }
lemma
zspan.fract_add_zspan
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "set.range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fract_eq_self {x : E} : fract b x = x ↔ x ∈ fundamental_domain b
by { classical ; simp only [basis.ext_elem_iff b, repr_fract_apply, int.fract_eq_self, mem_fundamental_domain, set.mem_Ico] }
lemma
zspan.fract_eq_self
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "basis.ext_elem_iff", "int.fract_eq_self", "set.mem_Ico" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fract_mem_fundamental_domain (x : E) : fract b x ∈ fundamental_domain b
fract_eq_self.mp (fract_fract b _)
lemma
zspan.fract_mem_fundamental_domain
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fract_eq_fract (m n : E) : fract b m = fract b n ↔ -m + n ∈ span ℤ (set.range b)
begin classical, rw [eq_comm, basis.ext_elem_iff b], simp_rw [repr_fract_apply, int.fract_eq_fract, eq_comm, basis.mem_span_iff_repr_mem, sub_eq_neg_add, map_add, linear_equiv.map_neg, finsupp.coe_add, finsupp.coe_neg, pi.add_apply, pi.neg_apply, ← (eq_int_cast (algebra_map ℤ K) _), set.mem_range], end
lemma
zspan.fract_eq_fract
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "algebra_map", "basis.ext_elem_iff", "basis.mem_span_iff_repr_mem", "eq_int_cast", "finsupp.coe_add", "finsupp.coe_neg", "int.fract_eq_fract", "linear_equiv.map_neg", "set.mem_range", "set.range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
norm_fract_le [has_solid_norm K] (m : E) : ‖fract b m‖ ≤ ∑ i, ‖b i‖
begin classical, calc ‖fract b m‖ = ‖∑ i, b.repr (fract b m) i • b i‖ : by rw b.sum_repr ... = ‖∑ i, int.fract (b.repr m i) • b i‖ : by simp_rw repr_fract_apply ... ≤ ∑ i, ‖int.fract (b.repr m i) • b i‖ : norm_sum_le _ _ ... ≤ ∑ i, ‖int.fract (b.repr m i)‖ * ‖b i‖ : by simp_r...
lemma
zspan.norm_fract_le
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "abs_one", "has_solid_norm", "int.abs_fract", "int.fract", "int.fract_lt_one", "mul_le_mul_of_nonneg_right", "norm_le_norm_of_abs_le_abs", "norm_smul", "norm_sum_le", "one_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_floor_self (k : K) : (floor (basis.singleton ι K) k : K) = ⌊k⌋
basis.ext_elem _ (λ _, by rw [repr_floor_apply, basis.singleton_repr, basis.singleton_repr])
lemma
zspan.coe_floor_self
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "basis.singleton", "basis.singleton_repr" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_fract_self (k : K) : (fract (basis.singleton ι K) k : K) = int.fract k
basis.ext_elem _ (λ _, by rw [repr_fract_apply, basis.singleton_repr, basis.singleton_repr])
lemma
zspan.coe_fract_self
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "basis.singleton", "basis.singleton_repr", "int.fract" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fundamental_domain_bounded [finite ι] [has_solid_norm K] : metric.bounded (fundamental_domain b)
begin casesI nonempty_fintype ι, use 2 * ∑ j, ‖b j‖, intros x hx y hy, refine le_trans (dist_le_norm_add_norm x y) _, rw [← fract_eq_self.mpr hx, ← fract_eq_self.mpr hy], refine (add_le_add (norm_fract_le b x) (norm_fract_le b y)).trans _, rw ← two_mul, end
lemma
zspan.fundamental_domain_bounded
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "finite", "has_solid_norm", "metric.bounded", "nonempty_fintype", "two_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
vadd_mem_fundamental_domain [fintype ι] (y : span ℤ (set.range b)) (x : E) : y +ᵥ x ∈ fundamental_domain b ↔ y = -floor b x
by rw [subtype.ext_iff, ← add_right_inj x, add_subgroup_class.coe_neg, ← sub_eq_add_neg, ← fract_apply, ← fract_zspan_add b _ (subtype.mem y), add_comm, ← vadd_eq_add, ← vadd_def, eq_comm, ← fract_eq_self]
lemma
zspan.vadd_mem_fundamental_domain
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "fintype", "set.range", "subtype.ext_iff", "subtype.mem" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exist_unique_vadd_mem_fundamental_domain [finite ι] (x : E) : ∃! v : span ℤ (set.range b), v +ᵥ x ∈ fundamental_domain b
begin casesI nonempty_fintype ι, refine ⟨-floor b x, _, λ y h, _⟩, { exact (vadd_mem_fundamental_domain b (-floor b x) x).mpr rfl, }, { exact (vadd_mem_fundamental_domain b y x).mp h, }, end
lemma
zspan.exist_unique_vadd_mem_fundamental_domain
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "finite", "nonempty_fintype", "set.range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fundamental_domain_measurable_set [measurable_space E] [opens_measurable_space E] [finite ι] : measurable_set (fundamental_domain b)
begin haveI : finite_dimensional ℝ E := finite_dimensional.of_fintype_basis b, let f := (finsupp.linear_equiv_fun_on_finite ℝ ℝ ι).to_linear_map.comp b.repr.to_linear_map, let D : set (ι → ℝ) := set.pi set.univ (λ i : ι, (set.Ico (0 : ℝ) 1)), rw ( _ : fundamental_domain b = f⁻¹' D), { refine measurable_set_pr...
lemma
zspan.fundamental_domain_measurable_set
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "finite", "finite_dimensional", "finite_dimensional.of_fintype_basis", "finsupp.linear_equiv_fun_on_finite", "linear_equiv.coe_to_linear_map", "linear_map.coe_comp", "linear_map.continuous_of_finite_dimensional", "measurable", "measurable_set", "measurable_set_Ico", "measurable_set_preimage", ...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_add_fundamental_domain [finite ι] [measurable_space E] [opens_measurable_space E] (μ : measure E) : is_add_fundamental_domain (span ℤ (set.range b)).to_add_subgroup (fundamental_domain b) μ
begin casesI nonempty_fintype ι, exact is_add_fundamental_domain.mk' (null_measurable_set (fundamental_domain_measurable_set b)) (λ x, exist_unique_vadd_mem_fundamental_domain b x), end
lemma
zspan.is_add_fundamental_domain
algebra.module
src/algebra/module/zlattice.lean
[ "measure_theory.group.fundamental_domain" ]
[ "finite", "measurable_space", "nonempty_fintype", "opens_measurable_space", "set.range" ]
For a ℤ-lattice `submodule.span ℤ (set.range b)`, proves that the set defined by `zspan.fundamental_domain` is a fundamental domain.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
submodule (R : Type u) (M : Type v) [semiring R] [add_comm_monoid M] [module R M] extends add_submonoid M, sub_mul_action R M : Type v.
structure
submodule
algebra.module.submodule
src/algebra/module/submodule/basic.lean
[ "algebra.module.linear_map", "algebra.module.equiv", "group_theory.group_action.sub_mul_action", "group_theory.submonoid.membership" ]
[ "add_comm_monoid", "add_submonoid", "module", "semiring", "sub_mul_action" ]
A submodule of a module is one which is closed under vector operations. This is a sufficient condition for the subset of vectors in the submodule to themselves form a module.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83