I do love the Casimir effect. Geometry of pressure differentials
   produces great rewards in output.

   [1]https://en.wikipedia.org/wiki/Efimov_state is a good place to
   start. The animated gif was from me, very precisely calibrated
   to bring the effect into two dimensions to illustrate it simply
   on two dimensional screens. [which are, of course not two
   dimensional at all, but figuratively speaking][2]efimov_scaling

References

   Visible links
   1. https://en.wikipedia.org/wiki/Efimov_state
   2. http://icopiedyou.com/wp-content/uploads/2015/10/efimov_scaling.gif