ScalingStacks

Lemma 5.1 [0323]

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Lemma 5.1

Let XX, ωϵ\omega_{\epsilon} be as in Theorem 4.5. Assume V​o​l​(X)=1Vol(X)=1. Then there exists a function I⁡(ϵ)I(\epsilon) depending only on ϵ\epsilon and JJ with I⁡(ϵ)≥C​ϵ5I(\epsilon)\geq C\epsilon^{5}, CC depending only on JJ, such that

(1) For any function ff on XX such that ∫Xf​ωϵ2=0\int_{X}f\omega_{\epsilon}^{2}=0,

‖d​f‖22≥I⁡(ϵ)​‖f‖42.\|df\|^{2}_{2}\geq I(\epsilon)\|f\|^{2}_{4}.

(2) For any function ff on XX,

‖d​f‖22≥I⁡(ϵ)​(‖f‖42−‖f‖22).\|df\|^{2}_{2}\geq I(\epsilon)(\|f\|^{2}_{4}-\|f\|^{2}_{2}).

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