Topological space structure on the opposite monoid and on the units group #
In this file we define topological_space
structure on Mᵐᵒᵖ
, Mᵃᵒᵖ
, Mˣ
, and add_units M
.
This file does not import definitions of a topological monoid and/or a continuous multiplicative
action, so we postpone the proofs of has_continuous_mul Mᵐᵒᵖ
etc till we have these definitions.
Tags #
topological space, opposite monoid, units
@[protected, instance]
Put the same topological space structure on the opposite monoid as on the original space.
Equations
@[protected, instance]
Equations
@[continuity]
@[continuity]
@[continuity]
@[continuity]
mul_opposite.op
as a homeomorphism.
Equations
- mul_opposite.op_homeomorph = {to_equiv := mul_opposite.op_equiv M, continuous_to_fun := _, continuous_inv_fun := _}
add_opposite.op
as a homeomorphism.
Equations
- add_opposite.op_homeomorph = {to_equiv := add_opposite.op_equiv M, continuous_to_fun := _, continuous_inv_fun := _}
@[simp]
theorem
mul_opposite.map_op_nhds
{M : Type u_1}
[topological_space M]
(x : M) :
filter.map mul_opposite.op (𝓝 x) = 𝓝 (mul_opposite.op x)
@[simp]
theorem
add_opposite.map_op_nhds
{M : Type u_1}
[topological_space M]
(x : M) :
filter.map add_opposite.op (𝓝 x) = 𝓝 (add_opposite.op x)
@[simp]
theorem
mul_opposite.map_unop_nhds
{M : Type u_1}
[topological_space M]
(x : Mᵐᵒᵖ) :
filter.map mul_opposite.unop (𝓝 x) = 𝓝 (mul_opposite.unop x)
@[simp]
theorem
add_opposite.map_unop_nhds
{M : Type u_1}
[topological_space M]
(x : Mᵃᵒᵖ) :
filter.map add_opposite.unop (𝓝 x) = 𝓝 (add_opposite.unop x)
@[simp]
theorem
add_opposite.comap_op_nhds
{M : Type u_1}
[topological_space M]
(x : Mᵃᵒᵖ) :
filter.comap add_opposite.op (𝓝 x) = 𝓝 (add_opposite.unop x)
@[simp]
theorem
mul_opposite.comap_op_nhds
{M : Type u_1}
[topological_space M]
(x : Mᵐᵒᵖ) :
filter.comap mul_opposite.op (𝓝 x) = 𝓝 (mul_opposite.unop x)
@[simp]
theorem
add_opposite.comap_unop_nhds
{M : Type u_1}
[topological_space M]
(x : M) :
filter.comap add_opposite.unop (𝓝 x) = 𝓝 (add_opposite.op x)
@[simp]
theorem
mul_opposite.comap_unop_nhds
{M : Type u_1}
[topological_space M]
(x : M) :
filter.comap mul_opposite.unop (𝓝 x) = 𝓝 (mul_opposite.op x)
@[protected, instance]
The units of a monoid are equipped with a topology, via the embedding into M × M
.
@[protected, instance]