Lemma 3.8. Assuming that:

$ψ : V \to ℝ_{\geq 0}$

Then there is

0 < t \leq ∥ ψ ∥_{\infty}

such that

Φ ({x : ψ (x) \geq t}) \leq \sqrt{2 q_{{\tilde{L}}_{G}} (ψ)} .