Some properties of the moduli of continuity of periodic functions in metric spaces

• Date: 2016
• Main Authors: Pichugov, S. A., Пичугов, С. А.
• Format: Article
• Language: Russian
• Published: Institute of Mathematics, NAS of Ukraine 2016
• Online Access: https://umj.imath.kiev.ua/index.php/umj/article/view/1951
• Journal Title: Ukrains’kyi Matematychnyi Zhurnal

Let $L_0(T)$) be the set of real-valued periodic measurable functions, let $\Psi : R^{+} \rightarrow R^{+}$ be the modulus of continuity, and let $$L_{\Psi} \equiv L_{\Psi} (T) = \left\{ f \in L_0(T) : \| f\| _{\Psi} := \frac1{2\pi} \int_T \Psi (| f(x)| )dx < \infty \right\}.$$ We stu...