English
The group topologies on γ are partially ordered by refinement: t ≤ s if every open set in s is open in t.
Русский
Групповые топологии на γ образуют частично упорядоченное множество по включению (упрощению): t ≤ s тогда, когда любое открытое множество в s также открыто в t.
LaTeX
$$$\\text{PartialOrder}(\\mathrm{GroupTopology}(\\alpha))$$$
Lean4
/-- The ordering on group topologies on the group `γ`. `t ≤ s` if every set open in `s` is also open
in `t` (`t` is finer than `s`). -/
@[to_additive /-- The ordering on group topologies on the group `γ`. `t ≤ s` if every set open in `s`
is also open in `t` (`t` is finer than `s`). -/
]
instance : PartialOrder (GroupTopology α) :=
PartialOrder.lift toTopologicalSpace toTopologicalSpace_injective