Zulip Chat Archive
Stream: maths
Topic: metric space stuff
Ashvni Narayanan (Mar 11 2021 at 11:09):
I am trying to prove that the space of locally constant functions are dense in the space of continuous functions. Things are rather open ended, in the sense that I am trying to work with the minimum amount of stuff needed. I don't understand why the last line gives me an error :
import measure_theory.integration
import algebra.group.hom
import ring_theory.int.basic
import data.padics.padic_integers
import set_theory.zfc
import topology.category.Profinite
import topology.locally_constant.algebra
import topology.algebra.continuous_functions
import topology.metric_space.basic
variables (X : Profinite)
open_locale big_operators
instance semi {R : Type*} [semiring R] : semimodule R (locally_constant X R) := sorry
variables {R : Type*} [ring R] {Γ₀ : Type*} [linear_ordered_comm_group_with_zero Γ₀] (v : valuation R Γ₀)
instance uniform [topological_space R] : uniform_space C(X, R) := sorry
instance completeness [topological_space R] : complete_space C(X, R) := sorry
--topo ring assumption not really needed
def inclusion [topological_space R] [topological_ring R] : locally_constant X R → C(X,R) := sorry
lemma sub [topological_space R] [topological_ring R] : function.injective (@inclusion X R _ _ _) := sorry
instance topo_space : topological_space (locally_constant ↥X R) := sorry
instance met [topological_space R] : metric_space C(X,R) := sorry
lemma dense_C [topological_space R] [topological_ring R] :
@dense (C(X,R)) _ (set.range (inclusion X)) :=
begin
rintros f,
rw mem_closure_iff_cluster_pt,
sorry,
end
Any help is appreciated, thank you!
Ashvni Narayanan (Mar 11 2021 at 12:34):
I figured it out, the topology did not match the one coming from the metric space, which was causing issues. Fixed now!
Last updated: Dec 20 2023 at 11:08 UTC