arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1902.08846math.LO
收藏

巴拿赫空间中绝对收敛的well-ordered级数的重排

Rearranging absolutely convergent well-ordered series in Banach spaces

Vedran Čačić, Marko Doko, Marko Horvat

摘要:

重新排列级数的项是一种有用的数学方法,而且我们知道什么时候可以这样做而不影响级数的收敛性或总和。例如,如果一系列实数绝对收敛,我们可以分别将偶数索引项和奇数索引项相加,或者将这些项排列在一个无限二维表中,先计算每列的和。更复杂的重新排序的可能性促使我们找到一个普遍的基本原则。我们在巴拿赫空间中证明了这样一个原理,在这里我们考虑指数超过ω但严格低于ω_1的良序级数。证明了对每一个以可数序数为指标的绝对收敛良序级数,若按任一可数序数重排该级数,则该级数的绝对收敛性及和保持不变.

英文摘要:

Reordering the terms of a series is a useful mathematical device, and much is known about when it can be done without affecting the convergence or the sum of the series. For example, if a series of real numbers absolutely converges, we can add the even-indexed and odd-indexed terms separately, or arrange the terms in an infinite two-dimensional table and first compute the sum of each column. The possibility of even more intricate re-orderings prompts us to find a general underlying principle. We identify such a principle in the setting of Banach spaces, where we consider well-ordered series with indices beyond ω, but strictly under ω_1 . We prove that for every absolutely convergent well-ordered series indexed by a countable ordinal, if the series is rearranged according to any countable ordinal, then the absolute convergence and the sum of the series remain unchanged.

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。

↑