The Compton wavelength expresses a fundamental limitation on measuring the position of a particle. This limitation depends on the mass m of the particle.

Imagine a system that is made up of N - a number of particles with average mass <m> and each of them is in some average volume <v>. This collection of particles is a system that has a total energy E and a diameter D. Can we construct a system in which each of these <m> are fundamentally confined where the confinement of each <m> is equal to the diameter of the system?