Abstract: 

It is natural in many transportation problems to privilege a grouped transportation rather than a diffused process. This originates transportation networks which exhibit branched structures.

A way to model this phenomenon consists in describing a discrete transportation network as an oriented weighted graph, subject to the Kirchhoff's laws, the weight on each edge representing the intensity of the flow of moving particles on that stretch. Then one associates to such network an energy which is proportional, per unit length, to a concave function of the weight, for instance a fractional power.

In this introductive talk, I will describe some features of the most common variational formulations of this problem.

For further information please write to elisur.magrini@unibocconi.it