Pinning of Fermionic Occupation Numbers

Mathias Christiandl, ETH - Institute of Theoretical Physics, Zurich

Résumé/abstract:

The Pauli exclusion principle is a constraint on the natural occupation numbers of fermionic states. It has been suspected since at least the 1970's, and only proved very recently, that there is a multitude of further constraints on these numbers, generalizing the Pauli exclusion principle. This is a beautiful mathematical result, but are there systems whose physics is governed by these constraints? In order to address this question, we studied a system of a few fermions connected by springs. As we varied the spring constant, the occupation numbers moved within the region allowed by the newly-found constraints. Strikingly, the path they traced hugs very close to the boundary of the allowed region, suggesting that the influence of the generalized constraints affects the system. I will discuss implications of these findings for the structure of few-fermion ground states; exploring the consequences for neutron stars remains the challenge.

Cette conférence s'adresse à tous, y compris les professeurs, les chercheurs et les étudiants des trois cycles.

Le café est servi à partir de 11h20.

Cette conférence est présentée par le Département de physique de l'Université de Montréal.