Page 1. Block Entropy of the XYZ Model: Exact Results and Numerical Study Cristian Degli Esposti Boschi CNISM and Dipartimento di Fisica, Università di Bologna Stefano Evangelisti Tesi di laurea in Fisica, Università di Bologna, Elisa Ercolessi, Francesco Ravanini, Fabio Ortolani, Dipartimento di Fisica and Sezione INFN, Bologna Italian Quantum Information Science Conference, 58 nov 2009, Scuola Normale Superiore, Pisa Page 2. Given a bipartite quantum system (A+B), the von Neumann entropy quantifies the entanglement of A with B if the whole system is in a pure state in particular the ground state of the Hamiltonian on (A+B) S=−tr A  A log A  A =tr B  =∣ 0 =∣0〉〈0∣ HAB∣0〉=E0∣0 〉 Page 3. ● Critical points of 1D quantum systems are typically described by (1+1) conformal field theories. ● Calabrese and Cardy [J. Stat. Mech. P06002 …