scholarly journals SEMICLASSICAL METHODS IN 2D QFT: SPECTRA AND FINITE-SIZE EFFECTS

2006 ◽  
Vol 21 (28) ◽  
pp. 2099-2115 ◽  
Author(s):  
VALENTINA RIVA
Keyword(s):  
Size Effects ◽  
Finite Size ◽  
Large Mass ◽  
Field Theories ◽  
Quantum Field Theories ◽  
Quantum Field ◽  
Finite Size Effects ◽  
Small Coupling ◽  
Semiclassical Methods ◽  
Semiclassical Expansion

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.

scholarly journals Log-periodic behavior of finite size effects in field theories with RG limit cycles

2004 ◽  
Vol 700 (1-3) ◽  
pp. 407-435 ◽  
Author(s):  
André LeClair ◽  
José María Román ◽  
Germán Sierra
Keyword(s):  
Limit Cycles ◽  
Size Effects ◽  
Finite Size ◽  
Field Theories ◽  
Finite Size Effects ◽  
Periodic Behavior

scholarly journals M$_k$ models: the field theory connection

2017 ◽  
Vol 3 (1) ◽  
Author(s):  
Thessa Fokkema ◽  
Kareljan Schoutens
Keyword(s):  
Field Theory ◽  
Finite Size ◽  
Field Theories ◽  
Quantum Field Theories ◽  
Quantum Field ◽  
Minimal Models ◽  
Size Spectra ◽  
Conformal Field ◽  
Lattice Fermions ◽  
Clustering Property

The M_kk models for 1D lattice fermions are characterised by {\cal N}=2 supersymmetry and by an order-kk clustering property. This paper highlights connections with quantum field theories (QFTs) in various regimes. At criticality the QFTs are minimal models of {\cal N}=2 supersymmetric conformal field theory (CFT) - we analyse finite size spectra on open chains with a variety of supersymmetry preserving boundary conditions. Specific staggering perturbations lead to a gapped regime corresponding to massive {\cal N}=2 supersymmetric QFT with Chebyshev superpotentials. At ‘extreme staggering’ we uncover a simple physical picture with degenerate supersymmetric vacua and mobile kinks. We connect this kink-picture to the Chebyshev QFTs and use it to derive novel CFT character formulas. For clarity the focus in this paper is on the simplest models, M_11, M_22 and M_33.

Sign in / Sign up

Export Citation Format

Share Document