We define and investigate the notion of twisted convex hull for a subset of the Heisenberg group H\mathbb{H}. We show that, while the twisted convex hull of two points is always a bounded set, the twisted convex hull of n > 2 points is, in general, an unbounded prism, with edges parallel to the t axis. These results shed some light on the twisted convex subsets of H\mathbb{H} in particular, we give a characterization of their interior.

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Andrea Calogero

Dip. di Statistica, Università di Milano-Bicocca, Via Bicocca degli Arcimboldi 8, 20126 Milano, Italy

andrea.calogero@unimib.it

Giovanna Carcano

Dip. di Metodi Quantitativi per le Scienze Economiche ed Aziendali, Università di Milano-Bicocca, Piazza Ateneo Nuovo 1, 20126 Milano, Italy

giovanna.carcano@unimib.it

Rita Pini

Dip. di Metodi Quantitativi per le Scienze Economiche ed Aziendali, Università di Milano-Bicocca, Piazza Ateneo Nuovo 1, 20126 Milano, Italy

rita.pini@unimib.it
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A. Calogero, G. Carcano, R. Pini. “Twisted Convex Hulls in the Heisenberg Group.” Journal of Convex Analysis 14 (2007), No. 3, 607–619. https://doi.org/10.68381/jca14036