Emergence of a Brunnian neutron state

Abstract

We discuss a quantum-statistical feature of non-relativistic identical fermions whose interaction is predominantly attractive at low energies. Specifically, we consider exotic, multi-neutron nuclei. From the enhancement of an arbitrarily small P-wave interaction between two nucleons, we infer the existence of a particle-stable nucleus composed entirely of neutrons. While we cannot specify the number of neutrons in the system, we predict that none of its substructures is bound. The independence of this deduction from the short-distance structure of the nuclear interaction and its consistency with deuteron, triton, and helium-4 properties is established.