Upper bounds for packings of spheres of several radii

  title={Upper bounds for packings of spheres of several radii},
  author={David de Laat and Fernando M{\'a}rio de Oliveira Filho and Frank Vallentin},
  journal={Forum of Mathematics, Sigma},
Abstract We give theorems that can be used to upper bound the densities of packings of different spherical caps in the unit sphere and of translates of different convex bodies in Euclidean space. These theorems extend the linear programming bounds for packings of spherical caps and of convex bodies through the use of semidefinite programming. We perform explicit computations, obtaining new bounds for packings of spherical caps of two different sizes and for binary sphere packings. We also… 
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