The embedding of a cancellative semigroup into itself by multiplication by a fixed element. #
If left-multiplication by any element is cancellative, left-multiplication by g
is an
embedding.
Equations
- mulLeftEmbedding g = { toFun := fun (h : G) => g * h, inj' := ⋯ }
Instances For
If left-addition by any element is cancellative, left-addition by g
is an
embedding.
Equations
- addLeftEmbedding g = { toFun := fun (h : G) => g + h, inj' := ⋯ }
Instances For
@[simp]
theorem
addLeftEmbedding_apply
{G : Type u_1}
[Add G]
[IsLeftCancelAdd G]
(g h : G)
:
(addLeftEmbedding g) h = g + h
@[simp]
theorem
mulLeftEmbedding_apply
{G : Type u_1}
[Mul G]
[IsLeftCancelMul G]
(g h : G)
:
(mulLeftEmbedding g) h = g * h
If right-multiplication by any element is cancellative, right-multiplication by g
is an
embedding.
Equations
- mulRightEmbedding g = { toFun := fun (h : G) => h * g, inj' := ⋯ }
Instances For
If right-addition by any element is cancellative, right-addition by g
is an
embedding.
Equations
- addRightEmbedding g = { toFun := fun (h : G) => h + g, inj' := ⋯ }
Instances For
@[simp]
theorem
mulRightEmbedding_apply
{G : Type u_1}
[Mul G]
[IsRightCancelMul G]
(g h : G)
:
(mulRightEmbedding g) h = h * g
@[simp]
theorem
addRightEmbedding_apply
{G : Type u_1}
[Add G]
[IsRightCancelAdd G]
(g h : G)
:
(addRightEmbedding g) h = h + g
theorem
mulLeftEmbedding_eq_mulRightEmbedding
{G : Type u_1}
[CommSemigroup G]
[IsCancelMul G]
(g : G)
:
theorem
addLeftEmbedding_eq_addRightEmbedding
{G : Type u_1}
[AddCommSemigroup G]
[IsCancelAdd G]
(g : G)
: