Pessimal packing shapes

Kallus, Yoav¹

¹ Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA

Geometry & topology, Tome 19 (2015) no. 1, pp. 343-363.

Résumé

We address the question of which convex shapes, when packed as densely as possible under certain restrictions, fill the least space and leave the most empty space. In each different dimension and under each different set of restrictions, this question is expected to have a different answer or perhaps no answer at all. As the problem of identifying global minima in most cases appears to be beyond current reach, in this paper we focus on local minima. We review some known results and prove these new results: in two dimensions, the regular heptagon is a local minimum of the double-lattice packing density, and in three dimensions, the directional derivative (in the sense of Minkowski addition) of the double-lattice packing density at the point in the space of shapes corresponding to the ball is in every direction positive.

Détail

DOI : 10.2140/gt.2015.19.343

Classification : 52A40, 52C15, 52C17
Keywords: packing, convex body, lattice, density

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