An important problem stemming from perturbation theory concerns description and understanding of operator $$\theta $$ -Holder functions. This article presents a survey of recent developments concerning operator $$\theta $$ -Holder functions with respect to symmetric quasi-norms.

中文翻译：

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运算符 $$\theta $$θ-Hölder 函数

来自扰动理论的一个重要问题涉及运算符 $$\theta $$ -Holder 函数的描述和理解。本文介绍了有关运算符 $$\theta $$ -Holder 函数关于对称准范数的最新发展的调查。