Kepler's Conjecture/Historical Note

Historical Note on Densest Sphere Packing
While it is in a certain sense obvious that the most efficient technique for packing spheres is the one traditionally used by greengrocer's to stack orange's, it proved challenging to actually prove it.


 * Many mathematicians believe, and all physicists know, that the density cannot exceed $\dfrac \pi {\sqrt {18} }$.

The proof was finally provided in $2014$ by.