In the theory of linear switching systems with discrete time, as in other areas of mathematics, the problem of studying the growth rate of the norms of all possible matrix products $A_{\sigma_{n}}\cdots A_{\sigma_{0}}$ with factors from a set of matrices $\mathscr{A}$ arises. So far, only for a relatively small number of classes of matrices $\mathscr{A}$ has it been possible to accurately describe the sequences of matrices that guarantee the maximum rate of increase of the corresponding norms. Moreover, in almost all cases studied theoretically, the index sequences $\{\sigma_{n}\}$ of matrices maximizing the norms of the corresponding matrix products have been shown to be periodic or so-called Sturmian, which entails a whole set of "good" properties of the sequences $\{A_{\sigma_{n}}\}$, in particular the existence of a limiting frequency of occurrence of each matrix factor $A_{i}\in\mathscr{A}$ in them. In the paper it is shown that this is not always the case: a class of matrices is defined consisting of two $2\times 2$ matrices, similar to rotations in the plane, in which the sequence $\{A_{\sigma_{n}}\}$ maximizing the growth rate of the norms $\|A_{\sigma_{n}}\cdots A_{\sigma_{0}}\|$ is not Sturmian. All considerations are based on numerical modeling and cannot be considered mathematically rigorous in this part; rather, they should be interpreted as a set of questions for further comprehensive theoretical analysis.
翻译:在具有离散时间的线性切换系统理论中,如在数学其他领域一样,研究所有可能的矩阵产品(A ⁇ sigma ⁇ n ⁇ ⁇ cdosts A ⁇ sigma ⁇ _0}$)的增长率,加上一组基质的因子($\mathscr{A}}$)。到目前为止,只有数量相对较少的基质类别($\mathscr{A}}}),才有可能准确描述保证相应规范最大增长率的矩阵序列。此外,几乎所有在理论上研究的案例中,将相应矩阵产品规范最大化的指数序列($ ⁇ sgma_ ⁇ n ⁇ }$_cddocks A ⁇ _groductions $_BAR___BAR_BAR_BAR_BAR_BAR_BAR_BAR_BAR_BAR__BAR_BAR_BAR_BAR_BAR_BAR_BAR_BAR_BAR_BAR_BAR__BAR___________________________________________________________________________________b__________________________________________________________________________________________________________________________________________________________________________________________________________