Acta Applicandae Mathematicae ( IF 1.6 ) Pub Date : 2020-07-10 , DOI: 10.1007/s10440-020-00349-3 J. Rodríguez-López , E. A. Sánchez-Pérez
Given a countable set of families \(\{\mathcal{D}_{k}:k \in \mathbb{N}\}\) of pseudometrics over the same set \(D\), we study the power-aggregations of this class, that are defined as convex combinations of integral averages of powers of the elements of \(\cup _{k} \mathcal{D}_{k}\). We prove that a Lipschitz function \(f\) is dominated by such a power-aggregation if and only if a certain property of super-additivity involving the powers of the elements of \(\cup _{k} \mathcal{D}_{k}\) is fulfilled by \(f\). In particular, we show that a pseudo-metric is equivalent to a power-aggregation of other pseudometrics if this kind of domination holds. When the super-additivity property involves a \(p\)-power domination, we say that the elements of \(\mathcal{D}_{k}\) are \(p\)-concave. As an application of our results, we prove under this requirement a new extension result of McShane-Whitney type for Lipschitz \(p\)-concave real valued maps.
中文翻译:
Lipschitz p $ p $的伪计量学的功率聚集和McShane-Whitney扩展定理-凹图
给定相同集合\(D \)上一组可计数的伪度量族\(\ {\ mathcal {D} _ {k}:k \ in \ mathbb {N} \} \),我们研究幂集合定义为\(\ cup _ {k} \ mathcal {D} _ {k} \)元素的幂的整数平均值的凸组合。我们证明,当且仅当涉及\(\ cup _ {k} \ mathcal {D}元素的幂的超可加性的某些属性时,Lipschitz函数\(f \)才由这种幂集合控制。_ {k} \)由\(f \)满足。特别是,我们证明了,如果这种支配地位成立,则伪度量等效于其他伪度量的功率聚集。当超可加性涉及\(p \)-幂控制时,我们说\(\ mathcal {D} _ {k} \)的元素是\(p \)-凹面。作为我们结果的应用,我们证明了在此要求下针对Lipschitz \(p \)-凹实值映射的McShane-Whitney类型的新扩展结果。