活動(dòng)名稱(chēng)：所有酉算子都是3循環(huán)的，多數(shù)是2循環(huán)的
時(shí) 間：2026年3月27日15:50-16:30
地 點(diǎn)：重慶國(guó)家應(yīng)用數(shù)學(xué)中心 308
主講 人：張遠(yuǎn)航 教授
主辦單位：數(shù)學(xué)科學(xué)學(xué)院
主講人簡(jiǎn)介：
張遠(yuǎn)航，吉林大學(xué)數(shù)學(xué)學(xué)院教授，研究方向?yàn)樗阕永碚摵退阕哟鷶?shù)，目前主要研究興趣是線(xiàn)性算子的結(jié)構(gòu)、單核C*-代數(shù)分類(lèi)、套代數(shù)的可逆元群連通性問(wèn)題。研究成果發(fā)表于J. Funct. Anal.、J. Noncommut. Geom.、J.Operator Theory、Math. Z.、Proc. Amer. Math. Soc.、Sci.China Math.、Studia Math.和Canad. J. Math.等知名數(shù)學(xué)期刊。
活動(dòng)簡(jiǎn)介：
Let H be a complex, separable Hilbert space (of finite or infinite dimension), and let U(H) denote the group of unitary operators on H. In the finite-dimensional setting, we prove that every unitary operator of determinant one can be expressed as the product of two operators, each unitarily equivalent to the n × n unitary cycle. In the infinite-dimensional setting, we prove that every unitary operator U is a product of three operators, each unitarily equivalent to the bilateral shift, and if the spectrum of U has nonzero Lebesgue measure, then U is a product of two operators, each unitarily equivalent to the bilateral shift. This work is joint with Laurent Marcoux, Matja?Omladi?and Heydar Radjavi.
