ﻻ يوجد ملخص باللغة العربية
We calculate the entanglement entropy of a non-contiguous subsystem of a chain of free fermions. The starting point is a formula suggested by Jin and Korepin, texttt{arXiv:1104.1004}, for the reduced density of states of two disjoint intervals with lattice sites $P={1,2,dots,m}cup{2m+1,2m+2,dots, 3m}$, which applies to this model. As a first step in the asymptotic analysis of this system, we consider its simplification to two disjoint intervals separated just by one site, and we rigorously calculate the mutual information between these two blocks and the rest of the chain. In order to compute the entropy we need to study the asymptotic behaviour of an inverse Toeplitz matrix with Fisher-Hartwig symbol using the the Riemann--Hilbert method.
We study the moments of the partial transpose of the reduced density matrix of two intervals for the free massless Dirac fermion. By means of a direct calculation based on coherent state path integral, we find an analytic form for these moments in te
The Ryu-Takayanagi conjecture contradicts $1+1$-dimensional CFT if we apply it to two far disjoint intervals because it predicts the product state. Instead of the conventional conjecture, we propose a holographic entanglement entropy formula that the
We reconsider the moments of the reduced density matrix of two disjoint intervals and of its partial transpose with respect to one interval for critical free fermionic lattice models. It is known that these matrices are sums of either two or four Gau
We consider the Heisenberg XXZ spin-$J$ chain ($Jinmathbb{N}/2$) with anisotropy parameter $Delta$. Assuming that $Delta>2J$, and introducing threshold energies $E_{K}:=Kleft(1-frac{2J}{Delta}right)$, we show that the bipartite entanglement entropy (
We give an upper bound of the relative entanglement entropy of the ground state of a massive Dirac-Majorana field across two widely separated regions $A$ and $B$ in a static slice of an ultrastatic Lorentzian spacetime. Our bound decays exponentially