The Lean 4 theorem `ritzInf_extension_le` in the `ChapterHermiteGalerkinFriedrichs` chapter of the timepiece formalization

-- Generated from ChapterHermiteGalerkinFriedrichs.lean — theorem BookProof.HermiteGalerkin.ritzInf_extension_le
import Mathlib
import Definitions.Def_ChapterHermiteGalerkinFriedrichs
open BookProof.HermiteGalerkin












open BookProof.FarisLavine BookProof.YangMillsFriedrichs BookProof.YangMillsFriedrichsLimit
open Filter Topology



variable {F : Type*} [NormedAddCommGroup F] [InnerProductSpace ℂ F]






variable {F : Type*} [NormedAddCommGroup F] [InnerProductSpace ℂ F]


















variable {F : Type*} [NormedAddCommGroup F] [InnerProductSpace ℂ F]



variable {D : Submodule ℂ F}

theorem BookProof.HermiteGalerkin.ritzInf_extension_le {Dom : Submodule ℂ F} (H : D →ₗ[ℂ] F) (A : Dom →ₗ[ℂ] F)
    (hA : IsPositiveSelfAdjointExtension H A) (hne : (ritzSet H D).Nonempty) :
    ritzInf A Dom ≤ ritzInf H D := by sorry