English
Polar of the closure equals polar of the set.
Русский
Поляр множества совпадает с поляром замыкания множества.
LaTeX
$$$\\operatorname{polar}(𝕜, \\overline{s}) = \\operatorname{polar}(𝕜, s)$$$
Lean4
@[simp]
theorem polar_closure (s : Set E) : StrongDual.polar 𝕜 (closure s) = StrongDual.polar 𝕜 s :=
((topDualPairing 𝕜 E).flip.polar_antitone subset_closure).antisymm <|
(topDualPairing 𝕜 E).flip.polar_gc.l_le <|
closure_minimal ((topDualPairing 𝕜 E).flip.polar_gc.le_u_l s) <| by
simpa [LinearMap.flip_flip] using (isClosed_polar _ _).preimage (inclusionInDoubleDual 𝕜 E).continuous