arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 1701.08129math.CA
收藏

HRT猜想的推广和限制原理

Extension and restriction principles for the HRT conjecture

Kasso A. Okoudjou

摘要:

HRT(Heil-Ramanathan-Topiwala)猜想是关于$\mathbb{R}$上的非零平方可积函数的时频位移的有限集合是否是线性无关的。这个长期存在的猜想在很大程度上仍然是开放的,即使在函数被假定为光滑的情况下。尽管如此,该猜想已经被证明了一些特殊的家庭的功能和/或特殊的点集。本文的主要贡献是一个归纳的方法来调查HRT猜想基于以下问题。假设HRT对于给定的($N$)点集和给定的函数为真。我们的特点,所有新的点,使猜想仍然为真的相同的功能和一组$N+1$点,通过增加这些新的点之一,原来的集合。为了实现这一点,我们引入了一个实值函数,其全局最大化描述HRT为真时。为了激励这种新方法,我们重新推导了$3$点集的HRT。随后,我们建立了新的结果点在$(1,n)$配置,并为一个家庭的对称$(2,3)$配置。此外,我们使用这些结果和其他已知的改进,以证明HRT持有某些家庭的$4$点。特别是,我们证明了HRT适用于任何一组$4$点和任何实值Schwartz函数。

英文摘要:

The HRT (Heil-Ramanathan-Topiwala) conjecture asks whether a finite collection of time-frequency shifts of a non-zero square integrable function on $\mathbb{R}$ is linearly independent. This longstanding conjecture remains largely open even in the case when the function is assumed to be smooth. Nonetheless, the conjecture has been proved for some special families of functions and/or special sets of points. The main contribution of this paper is an inductive approach to investigate the HRT conjecture based on the following question. Suppose that the HRT is true for a given set of ($N$) points and a given function. We characterize the set of all new points such that the conjecture remains true for the same function and the set of $N+1$ points obtained by adding one of these new points to the original set. To achieve this we introduce a real-valued function whose global maximizers describe when the HRT is true. To motivate this new approach we re-derive the HRT for sets of $3$ points. Subsequently, we establish new results for points in $(1,n)$ configurations, and for a family of symmetric $(2,3)$ configurations. Furthermore, we use these results and the refinements of other known ones to prove that the HRT holds for certain families of $4$ points. In particular, we show that the HRT holds for any set of $4$ points and any real-valued Schwartz function.

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。

↑