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Mathlib.GroupTheory.GroupAction.OfQuotient

MulAction and MulDistribMulAction of quotient group on fixed points #

Given a MulAction/MulDistribMulAction of a group G on A and a normal subgroup H of G, there is a MulAction/MulDistribMulAction of the quotient group G ⧸ H on fixedPoints H A.

instance MulAction.instQuotientSubgroupElemFixedPointsSubtypeMem {G : Type u_1} [Group G] {A : Type u_2} [MulAction G A] {H : Subgroup G} [H.Normal] :
MulAction (G H) (fixedPoints (↥H) A)
Equations
    @[simp]
    theorem MulAction.coe_quotient_smul_fixedPoints {G : Type u_1} [Group G] {A : Type u_2} [MulAction G A] {H : Subgroup G} [H.Normal] (g : G) (a : (fixedPoints (↥H) A)) :
    g a = g a
    @[simp]
    theorem MulAction.quotient_out_smul_fixedPoints {G : Type u_1} [Group G] {A : Type u_2} [MulAction G A] {H : Subgroup G} [H.Normal] (g : G H) (a : (fixedPoints (↥H) A)) :