Strong topologies on the space of continuous linear maps #
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In this file, we define the strong topologies on E →L[𝕜] F
associated with a family
𝔖 : set (set E)
to be the topology of uniform convergence on the elements of 𝔖
(also called
the topology of 𝔖
-convergence).
The lemma uniform_on_fun.has_continuous_smul_of_image_bounded
tells us that this is a
vector space topology if the continuous linear image of any element of 𝔖
is bounded (in the sense
of bornology.is_vonN_bounded
).
We then declare an instance for the case where 𝔖
is exactly the set of all bounded subsets of
E
, giving us the so-called "topology of uniform convergence on bounded sets" (or "topology of
bounded convergence"), which coincides with the operator norm topology in the case of
normed_space
s.
Other useful examples include the weak-* topology (when 𝔖
is the set of finite sets or the set
of singletons) and the topology of compact convergence (when 𝔖
is the set of relatively compact
sets).
Main definitions #
continuous_linear_map.strong_topology
is the topology mentioned above for an arbitrary𝔖
.continuous_linear_map.topological_space
is the topology of bounded convergence. This is declared as an instance.
Main statements #
continuous_linear_map.strong_topology.topological_add_group
andcontinuous_linear_map.strong_topology.has_continuous_smul
show that the strong topology makesE →L[𝕜] F
a topological vector space, with the assumptions on𝔖
mentioned above.continuous_linear_map.topological_add_group
andcontinuous_linear_map.has_continuous_smul
register these facts as instances for the special case of bounded convergence.
References #
TODO #
- add a type alias for continuous linear maps with the topology of
𝔖
-convergence?
Tags #
uniform convergence, bounded convergence
Given E
and F
two topological vector spaces and 𝔖 : set (set E)
, then
strong_topology σ F 𝔖
is the "topology of uniform convergence on the elements of 𝔖
" on
E →L[𝕜] F
.
If the continuous linear image of any element of 𝔖
is bounded, this makes E →L[𝕜] F
a
topological vector space.
Equations
The uniform structure associated with continuous_linear_map.strong_topology
. We make sure
that this has nice definitional properties.
Equations
The topology of bounded convergence on E →L[𝕜] F
. This coincides with the topology induced by
the operator norm when E
and F
are normed spaces.
Equations
Equations
Pre-composition by a fixed continuous linear map as a continuous linear map. Note that in non-normed space it is not always true that composition is continuous in both variables, so we have to fix one of them.
Post-composition by a fixed continuous linear map as a continuous linear map. Note that in non-normed space it is not always true that composition is continuous in both variables, so we have to fix one of them.
A pair of continuous (semi)linear equivalences generates a (semi)linear equivalence between the spaces of continuous (semi)linear maps.
A pair of continuous linear equivalences generates an continuous linear equivalence between the spaces of continuous linear maps.
Equations
- e₁.arrow_congr e₂ = e₁.arrow_congrSL e₂