[Merged by Bors] - feat(topology/algebra/group): continuity of action of a group on its own coset space #11772
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Given a subgroup
Γ
of a topological groupG
, there is an induced scalar action ofG
on the coset spaceG ⧸ Γ
, and there is also an induced topology onG ⧸ Γ
. We prove that this action is continuous in each variable, and, if the groupG
is locally compact, also jointly continuous.Co-authored-by: Alex Kontorovich 58564076+AlexKontorovich@users.noreply.github.com
See Zulip for motivation of the oddly specific lemmas in
topology/compact_open
. I am not sure whether the resultquotient_group.has_continuous_smul
truly needs the hypothesis[locally_compact_space G]
or whether this is an artifact of the proof method.