A symplectic ball packing is a collection of symplectic embeddings of disjoint standard symplectic balls into a symplectic manifold.
A symplectic embedding preserves the symplectic two-form; it is not required to preserve
the Euclidean distance. The standard ball 
has Euclidean radius 
and the standard symplectic
form, so 
is its capacity parameter.
Symplectic Ball Packing
See also
Ball, Gromov Width, Symplectic Manifold, Symplectic MapExplore with Wolfram|Alpha
References
Schlenk, F. "Symplectic Embedding Problems, Old and New." Bull. Amer. Math. Soc. 55, 139-182, 2018. https://doi.org/10.1090/bull/1587.Cite this as:
Weisstein, Eric W. "Symplectic Ball Packing." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/SymplecticBallPacking.html