English

The Cheeger constant as limit of Sobolev-type constants

Analysis of PDEs 2023-12-25 v2

Abstract

Let Ω\Omega be a bounded, smooth domain of RN,\mathbb{R}^{N}, N2.N\geq2. For 1<p<N1<p<N and 0<q(p)<p:=NpNp0<q(p)<p^{\ast}:=\frac{Np}{N-p} let λp,q(p):=inf{Ωupdx:uW01,p(Ω)  and  Ωuq(p)dx=1}. \lambda_{p,q(p)}:=\inf\left\{ \int_{\Omega}\left\vert \nabla u\right\vert ^{p}\mathrm{d}x:u\in W_{0}^{1,p}(\Omega)\text{ \ and \ }\int_{\Omega }\left\vert u\right\vert ^{q(p)}\mathrm{d}x=1\right\} . We prove that if limp1+q(p)=1,\lim_{p\rightarrow1^{+}}q(p)=1, then limp1+λp,q(p)=h(Ω)\lim_{p\rightarrow 1^{+}}\lambda_{p,q(p)}=h(\Omega), where h(Ω)h(\Omega) denotes the Cheeger constant of Ω.\Omega. Moreover, we study the behavior of the positive solutions wp,q(p)w_{p,q(p)} to the Lane-Emden equation div(wp2w)=wq2w,-\operatorname{div}(\left\vert \nabla w\right\vert ^{p-2}\nabla w)=\left\vert w\right\vert ^{q-2}w, as p1+.p\rightarrow1^{+}.

Keywords

Cite

@article{arxiv.2307.15618,
  title  = {The Cheeger constant as limit of Sobolev-type constants},
  author = {Grey Ercole},
  journal= {arXiv preprint arXiv:2307.15618},
  year   = {2023}
}

Comments

16 pages. Typing errors have been corrected, one reference has been added, and the abstract has been slightly modified