∀ {G : Type u} {α : Type w} {m : MeasurableSpace α} [inst : Group G] [inst_1 : MulAction G α]
  {μ : MeasureTheory.Measure α} [MeasureTheory.SMulInvariantMeasure G α μ] {s : Set α} (c : G), μ (c • s) = 0 ↔ μ s = 0