2006/09/14 by Valentina Riva, VALENTINA RIVA
Mathematics · Physics and Astronomy · #Nonlinear Photonic Systems #Quantum Mechanics and Non-Hermitian Physics #Quantum chaos and dynamical systems #cond-mat.stat-mech #hep-th #math-ph #math.MP
paper · pdf · doi:10.1142/s0217732306021621
published as Mod.Phys.Lett.A21:2099-2116,2006 · 16 pages, invited brief review for Mod. Phys. Lett. A
openalex publication_date 2006/09/14 · arxiv created 2006/10/05 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We review some recent results obtained in the analysis of two-dimensional quantum field theories by means of semiclassical techniques, which generalize methods introduced during the '70s by Dashen, Hasllacher and Neveu and by Goldstone and Jackiw. The approach is best suited to deal with quantum field theories characterized by a nonlinear interaction potential with different degenerate minima, that generates kink excitations of large mass in the small coupling regime. Under these circumstances, although the results obtained are based on a small coupling assumption, they are nevertheless nonperturbative, since the kink backgrounds around which the semiclassical expansion is performed are nonperturbative too. We will discuss the efficacy of the semiclassical method as a tool to control analytically spectrum and finite-size effects in these theories.