Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optimizing Packing Fraction in Granular Media Composed of Overlapping
  Spheres   What particle shape will generate the highest packing fraction when randomly
poured into a container? In order to explore and navigate the enormous search
space efficiently, we pair molecular dynamics simulations with artificial
evolution. Arbitrary particle shape is represented by a set of overlapping
spheres of varying diameter, enabling us to approximate smooth surfaces with a
resolution proportional to the number of spheres included. We discover a family
of planar triangular particles, whose packing fraction of $\phi \sim$ 0.73
outpaces almost all reported experimental results for random packings of
frictionless particles. We investigate how $\phi$ depends on the arrangement of
spheres comprising an individual particle and on the smoothness of the surface.
We validate the simulations with experiments using 3D-printed copies of the
simplest member of the family, a planar particle consisting of three
overlapping spheres with identical radius. Direct experimental comparison with
3D-printed aspherical ellipsoids demonstrates that the triangular particles
pack exceedingly well not only in the limit of large system size but also when
confined to small containers.

0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci