Jónsson's theorem in non-modular varieties

A version of Jónsson's Theorem, as previously generalized, holds in non-modular varieties. Received March 20, 2000; accepted in final form December 20, 2000.     

多重奇异积分的多线性交换子

引进了由多重奇异积分和BMO函数生成的多线性交换子,然后得到了此类算子从Lebesgue积空间到Lebesgue空间的有界性,最后也给出了此类算子的加权和向量值不等式.     

Characterization for commutators of n-dimensional fractional Hardy operators

In this paper, it was proved that the commutator Hβ,b generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from Lp1(Rn) to Lp2 (Rn) if and only if b is a C(M)O(Rn) function, where 1/p1 - 1/p2 = β/n, 1 ＜ p1 ＜∞, 0 ≤β＜ n. Furthemore,the characterization of Hβ,b on the homogenous Herz space (K)qα,p(Rn) was obtained.     

广义Calderón-Zygmund算子交换子在Hardy型空间上的有界性

[b,T]表示由Lipschitz函数b与广义Calderon-Zygmund算子T生成的交换子．本文研究了[b,T]在经典Hardy空间和Herz型Hardy空间上的有界性,并且在临界点情形证明了该交换子是从Hardy空间到弱Lebesgue空间以及Herz型Hardy到弱Herz空间有界的．     

Marcinkiewicz积分高阶交换子在加权Herz型Hardy空间中的有界性

讨论了-类具有齐性核的Marcinkiewicz积分高阶交换子在加权Herz型Hardy空间中的有界性,并得到了其端点估计.     

本征平方函数在极大变指数Herz空间上的有界性

我们证明了本征平方函数及其交换子在Herz空间$\dot{K}_{q(\cdot)}^{\alpha(\cdot), p),\theta}({\Bbb{R}}^n)$空间上的有界性,其中$\alpha$, $q$均为变指数。当$\alpha(\cdot)\equiv \alpha$为常数时,所得结果也是新的.     

Commutators of BMO functions and singular integral operators with non-smooth kernels on spaces of Homogeneous type of finite measure

Let X be a space of homogeneous type with finite measure. Let T be a singular integral operator which is bounded on Lp (X), 1 ＜ p ＜∞. We give a sufficient condition on the kernel k(x,y) of Tso that when a function b ∈ BMO (X) ,the commutator [b, T] (f) = T (b f) - bT (f) is aounded on spaces Lp for all p, 1 ＜ p ＜∞.     

核满足弱正则条件的多线性算子交换子的加权估计

本文主要研究核满足弱正则条件的算子与BMO函数生成的多线性交换子.建立了多线性交换子在加权Lebesgue空间的一些性质.     

Endp oint Estimates for Commutators of Fractional Integrals Asso ciated to Op erators with Heat Kernel Bounds

Let L be the infinitesimal generator of an analytic semigroup on L~2(R~n)with pointwise upper bounds on heat kernel,and denote by L~(-α/2)the fractional integrals of L.For a BMO function b(x),we show a weak type Llog L estimate of the commutators [b,L~(-α/2)](f)(x) = b(x)L~(-α/2)(f)(x)-L~(-α/2)(bf)(x).We give applications to large classes of differential operators such as the Schr¨odinger operators and second-order elliptic operators of divergence form.