Calibrations for minimal networks in a covering space setting

Carioni, Marcello; Pluda, Alessandra

ESAIM: Control, Optimisation and Calculus of Variations, Tome 26 (2020), article no. 40.

Suite au passage du modèle économique de la revue en S20, le texte intégral des articles des années 2019 et 2020 est accessible uniquement sur le site de l'éditeur et est réservé aux abonnés.

In this paper, we define a notion of calibration for an approach to the classical Steiner problem in a covering space setting and we give some explicit examples. Moreover, we introduce the notion of calibration in families: the idea is to divide the set of competitors in a suitable way, defining an appropriate (and weaker) notion of calibration. Then, calibrating the candidate minimizers in each family and comparing their perimeter, it is possible to find the minimizers of the minimization problem. Thanks to this procedure we prove the minimality of the Steiner configurations spanning the vertices of a regular hexagon and of a regular pentagon.

Classification : 49Q20, 49Q05, 57M10
Mots-clés : Minimal partitions, Steiner problem, covering spaces, calibrations

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