摘要

In this paper, we prove that if a finite disjoint union of translates U-k=1(n) if {f(k) (X -gamma)}(gamma is an element of Gamma k) in L-P(R-d) (1 < p < infinity) is a p';-Bessel sequence for some 1 < p'; < infinity, then the disjoint union Gamma = U-k=1(n) Gamma(k) has finite upper Beurling density, and that if U-k=1(n) {f(k)(X -gamma)}(gamma is an element of Gamma k) (C-q)-system with 1/p + 1/q = 1, then F has infinite upper Beurling density. Thus, no finite disjoint union of translates in LP(I) can form a p';-Bessel (Cq)-system for any 1 < p'; < pc. Furthermore, by using techniques from the geometry of Banach spaces, we obtain that, for 1 < p <= 2, no finite disjoint union of translates in L-P(R-d) can form an unconditional basis.

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