Quantum Quench in the Transverse Field Ising Chain

We consider the time evolution of observables in the transverse field Ising chain (TFIC) after a sudden quench of the magnetic field. We provide exact analytical results for the asymptotic time and distance dependence of one- and two-point correlation functions of the order parameter. We employ two complementary approaches based on asymptotic evaluations of determinants and form-factor sums. We prove that the stationary value of the two-point correlation function is not thermal, but can be described by a generalized Gibbs ensemble (GGE). The approach to the stationary state can also be understood in terms of a GGE. We present a conjecture on how these results generalize to particular quenches in other integrable models.Comment: 4 pages, 1 figur

Quantum Quench in the Transverse Field Ising chain I: Time evolution of order parameter correlators

We consider the time evolution of order parameter correlation functions after a sudden quantum quench of the magnetic field in the transverse field Ising chain. Using two novel methods based on determinants and form factor sums respectively, we derive analytic expressions for the asymptotic behaviour of one and two point correlators. We discuss quenches within the ordered and disordered phases as well as quenches between the phases and to the quantum critical point. We give detailed account of both methods.Comment: 65 pages, 21 figures, some typos correcte

Universal parity effects in the entanglement entropy of XX chains with open boundary conditions

We consider the Renyi entanglement entropies in the one-dimensional XX spin-chains with open boundary conditions in the presence of a magnetic field. In the case of a semi-infinite system and a block starting from the boundary, we derive rigorously the asymptotic behavior for large block sizes on the basis of a recent mathematical theorem for the determinant of Toeplitz plus Hankel matrices. We conjecture a generalized Fisher-Hartwig form for the corrections to the asymptotic behavior of this determinant that allows the exact characterization of the corrections to the scaling at order o(1/l) for any n. By combining these results with conformal field theory arguments, we derive exact expressions also in finite chains with open boundary conditions and in the case when the block is detached from the boundary.Comment: 24 pages, 9 figure

Robotic treatment of colorectal endometriosis: technique, feasibility and short-term results

background: Deep infiltrating endometriosis (DIE) is a complex disease that impairs the quality of life and the fertility of women. Since a medical approach is often insufficient, a minimally invasive approach is considered the gold standard for complete disease excision. Roboticassisted surgery is a revolutionary approach, with several advantages compared with traditional laparoscopic surgery. methods: From March 2010 to May 2011, we performed 22 consecutive robotic-assisted complete laparoscopic excisions of DIE endometriosis with colorectal involvement. All clinical data were collected by our team and all patients were interviewed preoperatively and 3 and 6 months post-operatively and yearly thereafter regarding endometriosis-related symptoms. Dysmenorrhoea, dyschezia, dyspareunia and dysuria were evaluated with a 10-point analog rating scale. results: There were 12 patients, with a median larger endometriotic nodule of 35 mm, who underwent segmental resection, and 10 patients, with a median larger endometriotic nodule of 30 mm, who underwent complete nodule debulking by colorectal wall-shaving technique. No laparotomic conversions were performed, nor was any blood transfusion necessary. No intra-operative complications were observed and, in particular, there were no inadvertent rectal perforations in any of the cases treated by the shaving technique. None of the patients had ileostomy or colostomy. No major post-operative complications were observed, except one small bowel occlusion 14 days post-surgery that was resolved in 3 days with medical treatment. Post-operatively, a statistically significant improvement of patient symptoms was shown for all the investigated parameters. conclusions: To our knowledge, this is the first study reporting the feasibility and short-term results and complications of laparoscopic robotic-assisted treatment of DIE with colorectal involvement.We demonstrate that this approach is feasible and safe, without conversion to laparotomy

Peritoneal carcinosis of ovarian origin

Epithelial ovarian cancer (EOC) is the second most common genital malignancy in women and is the most lethal gynecological malignancy, with an estimated five-year survival rate of 39%. Despite efforts to develop an effective ovarian cancer screening method, 60% of patients still present with advanced disease. Comprehensive management using surgical cytoreduction to decrease the tumor load to a minimum, and intraperitoneal chemotherapy to eliminate microscopic disease on peritoneal surface, has the potential to greatly improve quality of life and to have an impact on survival in ovarian cancer patients. Despite achieving clinical remission after completion of initial treatment, most patients (60%) with advanced EOC will ultimately develop recurrent disease or show drug resistance; the eventual rate of curability is less than 30%. Given the poor outcome of women with advanced EOC, it is imperative to continue to explore novel therapies.

Non-equilibrium dynamics of isolated quantum systems

The non-equilibrium dynamics of isolated quantum systems represent a theoretical and experimental challenge raising many fundamental questions with applications to different fields of modern physics. In these proceedings, we briefly review some of the recent findings on the subject, with particular emphasis to the existence of stationary expectation values of local observables and to their statistical mechanics description. It turns out that the appropriate statistical ensemble describing these asymptotic values depends on whether the Hamiltonian governing the time evolution is integrable or not