8 papers · 1 filter
Sharp Truncated Difference Estimates for Nonlocal Nonconvex Functionals Defined by Superlevel Sets
Feng Dai, Dachun Yang, Wen Yuan +1
Let and . In this article, we consider a family of nonlocal nonconvex functionals with a real parameter and est…
Sharp Quantitative Matrix-Weighted Bounds for Fractional Integrals and Sobolev Inequalities
Dachun Yang, Wen Yuan, Mingdong Zhang
For , , , and , we obtain the following matrix-weighted boundedness of the fractional integral : for an…
Sharp Matrix-Weighted Lower Bounds for Non-Degenerate Convolution Calderón--Zygmund Operators
Fan Bu, Dachun Yang, Wen Yuan
Let be a convolution Calderón--Zygmund operator satisfying Hytönen's non-degeneracy condition. We prove that, for every and , there exists a positive co…
Local Matrix Muckenhoupt Weights and Quantitative Weighted Inequalities Achieving Global Best Known Exponents
Tuomas Hytönen, Dachun Yang, Wen Yuan +1
In this article, we give various real-variable properties of local Muckenhoupt matrix weights and establish the quantitative boundedness of several operators on local matrix-we…
Weak-type characterizations of Sobolev and bounded variation spaces on metric measure spaces
Tuomas P. Hytönen, Dachun Yang, Wen Yuan +1
Given a complete doubling metric measure space supporting a Poincaré inequality, we prove weak-type characterizations of the Sobolev space and the spac…
Real-Variable Characterizations and Their Applications of Anisotropic Besov Spaces with Matrix Weights
Fan Bu, Shuaijun Feng, Qingying Xue +2
Let , , and . In this article, we develop a theory of matrix-weighted anisotropic Besov spaces associated with an expansive matrix $…
Fractional Gagliardo--Nirenberg Inequalities: Pointwise Estimates,Sharp Asymptotics, and Optimal Target Spaces
Pingxu Hu, Yinqin Li, Dachun Yang +1
We establish two pointwise estimates for fractional difference operators, tracking explicitly the dependence of the constants on the smoothness index . Using these, with…
Optimal Weak-Type Estimates and Their Applications of Lifted Rough Maximal Operators
Dachun Yang, Wen Yuan, Yirui Zhao
Let and with . In this article, we introduce a new family of lifted rough maximal operators $\{\mathcal{M}_…