Let $W^{1,p} (\mathbb{R}^n)$ be the sobolev space, and $W^{-1,p^{\prime}} (\mathbb{R}^n)$ be the it's dual space.
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I know $||f||_{L^2} \leq ||f||^{\frac{1}{2}}_{W^{1,2}} ||f||^{\frac{1}{2}}_{W^{-1,2}} \ \forall f \in W^{1,2}$.
Let $1 Is there a $1 \leq r \leq \infty , C>0, 0<\theta<1$ such that $||f||_{L^r} \leq C ||f||^{\theta}_{W^{1,q}} ||f||^{1- \theta}_{W^{-1,q^{\prime}}} $?