English

Quantitative John-Nirenberg inequalities at different scales

Classical Analysis and ODEs 2020-10-06 v1

Abstract

We provide an abstract estimate of the form ffQ,μX(Q,dμY(Q))c(μ,Y)ψ(X)fBMO(dμ) \|f-f_{Q,\mu}\|_{X \left(Q,\frac{\mathrm{d} \mu}{Y(Q)}\right)}\leq c(\mu,Y)\psi(X)\|f\|_{\mathrm{BMO}(\mathrm{d}\mu)} for all cubes QQ in Rn\mathbb{R}^n and every function fBMO(dμ)f\in \mathrm{BMO}(\mathrm{d}\mu), where μ\mu is a doubling measure in Rn\mathbb{R}^n, YY is some positive functional defined on cubes, X(Q,dww(Q))\|\cdot \|_{X \left(Q,\frac{\mathrm{d} w}{w(Q)}\right)} is a sufficiently good quasi-norm and c(μ,Y)c(\mu,Y) and ψ(X)\psi(X) are positive constants depending on μ\mu and YY, and XX, respectively. That abstract scheme allows us to recover the sharp estimate ffQ,μLp(Q,dμ(x)μ(Q))c(μ)pfBMO(dμ),p1 \|f-f_{Q,\mu}\|_{L^p \left(Q,\frac{\mathrm{d} \mu(x)}{\mu(Q)}\right)}\leq c(\mu)p\|f\|_{\mathrm{BMO}(\mathrm{d}\mu)}, \qquad p\geq1 for every cube QQ and every fBMO(dμ)f\in \mathrm{BMO}(\mathrm{d}\mu), which is known to be equivalent to the John-Nirenberg inequality, and also enables us to obtain quantitative counterparts when LpL^p is replaced by suitable strong and weak Orlicz spaces and Lp()L^{p(\cdot)} spaces. Besides the aforementioned results we also generalize Theorem 1.2 in [OPRRR20] to the setting of doubling measures and obtain a new characterization of Muckenhoupt's AA_\infty weights.

Keywords

Cite

@article{arxiv.2010.01221,
  title  = {Quantitative John-Nirenberg inequalities at different scales},
  author = {Javier C. Martínez-Perales and Ezequiel Rela and Israel P. Rivera-Ríos},
  journal= {arXiv preprint arXiv:2010.01221},
  year   = {2020}
}
R2 v1 2026-06-23T18:59:20.747Z