A boxing Inequality for the fractional perimeter

Autor: Daniel Spector, Augusto C. Ponce
Přispěvatelé: UCL - SST/IRMP - Institut de recherche en mathématique et physique
Rok vydání: 2020
Předmět:
Zdroj: Scuola Normale Superiore di Pisa. Annali. Classe di Scienze, Vol. 20, p. 107–141 (2020)
ISSN: 2036-2145
0391-173X
DOI: 10.2422/2036-2145.201711_012
Popis: We prove the Boxing inequality: $$\mathcal{H}^{d-\alpha}_\infty(U) \leq C\alpha(1-\alpha)\int_U \int_{\mathbb{R}^{d} \setminus U} \frac{\mathrm{d}y \, \mathrm{d}z}{|y-z|^{\alpha+d}},$$ for every $\alpha \in (0,1)$ and every bounded open subset $U \subset \mathbb{R}^d$, where $\mathcal{H}^{d-\alpha}_\infty(U)$ is the Hausdorff content of $U$ of dimension $d -\alpha$ and the constant $C > 0$ depends only on $d$. We then show how this estimate implies a trace inequality in the fractional Sobolev space $W^{\alpha, 1}(\mathbb{R}^d)$ that includes Sobolev's $L^{\frac{d}{d - \alpha}}$ embedding, its Lorentz-space improvement, and Hardy's inequality. All these estimates are thus obtained with the appropriate asymptotics as $\alpha$ tends to $0$ and $1$, recovering in particular the classical inequalities of first order. Their counterparts in the full range $\alpha \in (0, d)$ are also investigated.
Databáze: OpenAIRE