Weighted norm inequalities, off-diagonal estimates and elliptic operators
Pascal Auscher, José Maria Martell
备注:
survey for the El Escorial 2008 proceedings
发表信息:
Harmonic Analysis and Partial Differential Equations. Proceedings of the 8th International Conference on Harmonic Analysis and Partial Differential Equations, El Escorial, June 16-20, 2008, Contemporary Mathematics 505 (2010), 61--83
We give an overview of the generalized Calderón-Zygmund theory for "non-integral" singular operators, that is, operators without kernels bounds but appropriate off-diagonal estimates. This theory is powerful enough to obtain weighted estimates for such operators and their commutators with $\BMO$ functions. $L^p-L^q$ off-diagonal estimates when $p\le q$ play an important role and we present them. They are particularly well suited to the semigroups generated by second order elliptic operators and the range of exponents $(p,q)$ rules the $L^p$ theory for many operators constructed from the semigroup and its gradient. Such applications are summarized.
Weighted norm inequalities, off-diagonal estimates and elliptic operators. Part I: General operator theory and weights
这是一系列四篇文章的第一部分。在这项工作中,我们感兴趣的加权范数估计。我们把重点放在两个不同性质的结果:一个是基于一个好的$λ$不等式与两个参数和其他使用Calderón-Zygmund分解。这些结果很好地适用于奇异的“非积分”算子及其具有有界平均振荡函数的算子。奇异意味着它们是0阶的,“非整数”意味着它们没有一个带有大小估计的核的整表示,甚至是粗略的,所以它们可能不在$1 < p < \infty$的所有$L^p$空间上有界。然后用适当的局部$L^p-L^q$估计值替换逐点估计值。我们获得加权$L^p$估计的$p$的范围是不同的$(1,\infty)$和隔离的权利类的权重。特别是,我们证明了这样一个类的外推定理' à la Rubio de Francia',从而向量值估计。