The object of this paper is to extend two partial results, one positive and one negative, concerning the a.e. convergence of Poisson integrals on generalized half-planes equivalent to bounded symmetric domains. These results involve the distinction between "restricted" and "unrestricted" convergence, which already arose in the case of domains which are equivalent to product of half-planes (for this case see e.g. [Z, Chapter 17]). For these special domains there is restricted convergence for L", p^l, and unrestricted convergence for IS, p> 1. The L1 result of restricted convergence for various other tube domains was obtained more recently in [WJ and [S]. The techniques set forth in [Wx] and [S] provide the starting point of our treatment here. Turning to the case of the general bounded symmetric domains, the positive results of [WJ and [W2] show that the Poisson integral of a function/on one of the domains in question converges restrictedly to/at a.e. point of the boundary if fie L",p> 1. It is demonstrated below that the condition/G L1 is also sufficient for restricted a.e. convergence, and that the Poisson integral of a measure has its Radon-Nikodym derivative as a restricted a.e. limit. On the other hand, it was essentially shown in [SWW] that for domains of the above type, there exists p0> 1 such that every LP class, p
JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. The Johns Hopkins University Press is collaborating with JSTOR to digitize, preserve and extend access to American Journal of Mathematics.
Introduction. The main purpose of this paper is the extension to all compact Lie groups of results concerning translation invariant operators which are known for the n-torus.
Suppose that G is a compact Lie group and A is a maximal collection of inequivalent irreducible unitary representations of G. Given a bounded multi-sequence {mX}XIA, mx C C, define the operator T on the space of finite linear combinations of entry functions on G by writing (Tf)A (X) = mx? (A), where j(A) f(x)A(x) dx. T commutes with left and right translation; if for some p, T can be extended to a bounded operator on all of LP (G), then {mx} is called a multiplier for LP(G).The problem we consider is that of characterizing such multipliers.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.