English

Non-linear ground state representations and sharp Hardy inequalities

Analysis of PDEs 2008-11-15 v2 Mathematical Physics math.MP Spectral Theory

Abstract

We determine the sharp constant in the Hardy inequality for fractional Sobolev spaces. To do so, we develop a non-linear and non-local version of the ground state representation, which even yields a remainder term. From the sharp Hardy inequality we deduce the sharp constant in a Sobolev embedding which is optimal in the Lorentz scale. In the appendix, we characterize the cases of equality in the rearrangement inequality in fractional Sobolev spaces.

Keywords

Cite

@article{arxiv.0803.0503,
  title  = {Non-linear ground state representations and sharp Hardy inequalities},
  author = {Rupert L. Frank and Robert Seiringer},
  journal= {arXiv preprint arXiv:0803.0503},
  year   = {2008}
}

Comments

AMSLaTeX, 22 pages; extension of the result to the case N<ps

R2 v1 2026-06-21T10:18:18.272Z