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arXiv 0705.4277math.FA
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紧群上的卷积与陪集空间的Fourier代数

Convolutions on compact groups and Fourier algebras of coset spaces

Brian E. Forrest, Ebrahim Samei, Nico Spronk

摘要:

在本说明中,我们研究两个相关的问题。(1)对于紧群G,由$u X v |-> u*v' ($ v '(s)=v(s^{-1})$) and $ u X v给出的A(G × G)上的卷积映射的值域是什么|-> u*v$?(2)对于一个局部紧群G和一个紧子群K,陪集空间A(G/K)的Fourier代数的顺从性是什么?代数A(G/K)是由第一作者定义和研究的。在回答第一个问题时,我们得到了不允许有限指数交换子群的紧群A(G)的一些新的子代数。利用这些代数,我们可以找到许多情况下,A(G/K)失败的最基本的顺从性质:运营商弱顺从。然而,使用不同的技术,我们证明了,如果G的单位元的连通分支是阿贝尔,那么A(G/K)总是满足更强的性质,它是超Tauberian,这是一个概念,由第二命名的作者。我们还建立了一类包含最大概周期群的群A(G/K)的算子顺从性的准则。

英文摘要:

In this note we study two related questions. (1) For a compact group G, what are the ranges of the convolution maps on A(GXG) given for u,v in A(G) by $u X v |-> u*v' ($v'(s)=v(s^{-1})$) and $u X v |-> u*v$? (2) For a locally compact group G and a compact subgroup K, what are the amenability properties of the Fourier algebra of the coset space A(G/K)? The algebra A(G/K) was defined and studied by the first named author. In answering the first question, we obtain for compact groups which do not admit an abelian subgroup of finite index, some new subalgebras of A(G). Using those algebras we can find many instances in which A(G/K) fails the most rudimentary amenability property: operator weak amenability. However, using different techniques, we show that if the connected component of the identity of G is abelian, then A(G/K) always satisfies the stronger property that it is hyper-Tauberian, which is a concept developed by the second named author. We also establish a criterion which characterises operator amenability of A(G/K) for a class of groups which includes the maximally almost periodic groups.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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