Bezdek and Kuperberg (1991) have constructed packings of identical ellipsoids of densities arbitrarily close to
(Sloane's A093824), greater than the maximum density of
(Sloane's A093825)
that is possible for sphere packing
(Sloane 1998), as established by proof of the Kepler
conjecture. Furthermore, J. Wills has modified the ellipsoid packing to
yield an even higher density of (Bezdek
and Kuperberg 1991).
Donev et al. (2004) showed that a maximally random jammed state of M&Ms chocolate candies has a packing density of about 68%, or 4% greater than spheres.
Furthermore, Donev et al. (2004) also showed by computer simulations other
ellipsoid packings resulted in random packing densities approaching that of the densest
sphere packings, i.e., filling nearly 74% of space.
Bezdek, A. and Kuperberg, W. In Applied Geometry and Discrete Mathematics: The Victor Klee Festschrift
(Ed. P. Gritzmann and B. Sturmfels). Providence, RI: Amer. Math. Soc.,
pp. 71-80, 1991.
Donev, A.; Cisse, I.; Sachs, D.; Variano, E. A.; Stillinger, F. H.; Connelly, R.; Torquato, S.; and Chaikin, P. M. "Improving the Density of Jammed Disordered
Packings using Ellipsoids." Science, 303, 990-993, 2004.
Sloane, N. J. A. "Kepler's Conjecture Confirmed." Nature 395,
435-436, 1998.
Sloane, N. J. A. Sequences A093824 and A093825 in "The On-Line Encyclopedia of Integer Sequences."
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