Journal of Dynamics and Differential Equations ( IF 1.4 ) Pub Date : 2020-03-16 , DOI: 10.1007/s10884-020-09839-2 Marek Fila , Johannes Lankeit
We improve the Gagliardo–Nirenberg inequality
$$\begin{aligned} \Vert \varphi \Vert _{L^q({\mathbb {R}}^n)} \le C \Vert \nabla \varphi \Vert _{L^r({\mathbb {R}}^n)} {\mathcal {L}}^{-(\frac{1}{q} - \frac{n-2}{2n})} (\Vert \nabla \varphi \Vert _{L^r({\mathbb {R}}^n)}), \end{aligned}$$\(r=2\), \(0<q<\frac{2n}{(n-2)_+}\), \({\mathcal {L}}\) generalizing \({\mathcal {L}}(s)=\ln ^{-1}\frac{2}{s}\) for \(0<s<1\), from Fila and Winkler (Adv Math 357, 2019. https://doi.org/10.1016/j.aim.2019.106823) for rapidly decaying functions (\(\varphi \in W^{1,2}({\mathbb {R}}^n){\setminus }\{0\}\) with finite \(K=\int _{{\mathbb {R}}^n} \mathcal {L}(|\varphi |)\)) by specifying the dependence of C on K and by allowing arbitrary \(r\ge 1\).
中文翻译:
快速衰变函数的Gagliardo-Nirenberg型不等式
我们改善了加利亚多-尼伦贝格不等式
$$ \ begin {aligned} \ Vert \ varphi \ Vert _ {L ^ q({\ mathbb {R}} ^ n)} \ le C \ Vert \ nabla \ varphi \ Vert _ {L ^ r({\ mathbb {R}} ^ n)} {\数学{L}} ^ {-(\ frac {1} {q}-\ frac {n-2} {2n})}}(\ Vert \ nabla \ varphi \ Vert _ {L ^ r({\ mathbb {R}} ^ n)}),\ end {aligned} $$\(r = 2 \),\(0 <q <\ frac {2n} {(n-2)_ +} \),\({\ mathcal {L}} \)推广\({\ mathcal {L }}(s)= \ ln ^ {-1} \ frac {2} {s} \)为\(0 <s <1 \),来自Fila和Winkler(Adv Math 357,2019. https:// doi .org / 10.1016 / j.aim.2019.106823)用于快速衰减的函数(\(\ varphi \ in W ^ {1,2}({\ mathbb {R}} ^ n){\ setminus} \ {0 \} \ ),通过指定C对K的依赖关系并允许任意\(r )来使用有限\(K = \ int _ {{\ mathbb {R}} ^ n} \ mathcal {L}(| \ varphi |)\))\ ge 1 \)。