Item

Abstract

We determine the reduced density matrix of chiral fermions on the torus, for
an arbitrary set of disjoint intervals and generic torus modulus. We find the
resolvent, which yields the modular Hamiltonian in each spin sector. Together
with a local term, it involves an infinite series of bi-local couplings, even
for a single interval. These accumulate near the endpoints, where they become
increasingly redshifted. Remarkably, in the presence of a zero mode, this set
of points 'condenses' within the interval at low temperatures, yielding
continuous non-locality.