Ferromagnetism in the Hubbard model with an infinite-range hopping

TL;DR

This paper proves that the ground state of the Hubbard model with infinite-range hopping and a specific electron count exhibits ferromagnetism, confirming a recent conjecture in condensed matter physics.

Contribution

It provides a rigorous proof confirming the conjecture that the ground state is ferromagnetic in this specific Hubbard model variant.

Findings

Ground state is ferromagnetic and fully polarized.

Confirms the recent conjecture about the model.

Provides a rigorous mathematical proof.

Abstract

We prove, as recently conjectured, that the ground state of the Hubbard Hamiltonian with an infinite-range hopping, when the number of electrons $N_e=N+1$ ($N$ being the number of sites), is ferromagnetic fully polarized.