Related papers: Fixed Point Four-Fermi Theories
Four-fermi models in dimensionality $2<d<4$ exhibit an ultra-violet stable renormalization group fixed point at a strong value of the coupling constant where chiral symmetry is spontaneously broken. The resulting field theory describes…
We present results from numerical simulations of three different 3d four-fermion models that exhibit Z_2, U(1), and SU(2) x SU(2) chiral symmetries, respectively. We performed the simulations by using the hybrid Monte Carlo algorithm. We…
We present Monte Carlo simulation results for the three dimensional Thirring model for numbers of fermion flavors N_f=4 and 6. For N_f=4 we find a second order chiral symmetry breaking transition at strong coupling, corresponding to an…
We investigate the UV fixed-point structure of the three-dimensional Thirring model by means of the functional renormalization group (RG). We classify all possible 4-fermi interactions compatible with the present chiral and discrete…
We investigate a class of relativistic fermion theories in 2<d<4 space-time dimensions with continuous chiral U(Nf)xU(Nf) symmetry. This includes a number of well-studied models, e.g., of Gross-Neveu and Thirring type, in a unified…
We formulate the three dimensional Thirring model on a spacetime lattice and study it for various even numbers of fermion flavors N_f by Monte Carlo simulation. We find clear evidence for spontaneous chiral symmetry breaking at strong…
In (2+1) dimensions, we consider the model of a $N$ flavor, two-component fermionic field interacting through a Chern-Simons field besides a four fermion self-interaction which consists of a linear combination of the Gross-Neveu and…
Certain approximate solutions of the continuum Schwinger-Dyson Equations (SDEs) predict chiral symmetry breaking in the 3d Thirring model when the number of fermion flavors N_f<4.32 whereas others predict symmetry breaking for all N_f. Our…
We analyze the finite temperature chiral restoration transition of the $(D=d+1)$-dimensional Gross-Neveu model for the case of a large number of flavors and fixed total fermion number. This leads to the study of the model with a nonzero…
By means of the Lee-Shrock transformation we generalize the 2D Gross-Neveu (GN$_2$) model to a U(1) gauge theory with charged fermion and scalar fields in 2D ($\chi U \phi_2$ model). The $\chi U \phi_2$ model is equivalent to the GN$_2$…
We discuss fixed point actions for various types of free lattice fermions. The iterated block spin renormalization group transformation yields lines of local but chiral symmetry breaking fixed points. For staggered fermions at least the…
We study the dynamical breaking of chiral symmetry in the 3-d Thirring model for a small number of fermion species. The critical point is identified by fitting lattice data to an equation of state. The spectrum of the theory is studied to…
I review three different non-perturbative approaches to the three dimensional Thirring model: the 1/N_f expansion, Schwinger-Dyson equations, and Monte Carlo simulation. Simulation results are presented to support the existence of a…
Perturbing the standard Gross-Neveu model for $N^3$ fermions by quartic interactions with the appropriate tensorial contraction patterns, we reduce the original $U(N^3)$ symmetry to either $U(N)\times U(N^2)$ or $U(N)\times U(N)\times…
Large-N expansions and computer simulations indicate that the universality class of the finite temperature chiral symmetry restoration transition in the 3D Gross-Neveu model is mean field theory. This is a counterexample to the standard…
We use the functional renormalization group and the $\epsilon$-expansion concertedly to explore multicritical universality classes for coupled $\bigoplus_i O(N_i)$ vector-field models in three Euclidean dimensions. Exploiting the…
Previous results on fermion chirality-flipping four-point functions are extended to $SU(N)$ gauge theories. The problem is purely non-perturbative, and it is approached by truncating the Schwinger-Dyson hierarchy. The large-$N$ limit also…
A hybrid of the critical three dimensional Gross-Neveu and Thirring models deformed by explicit parity breaking operators is studied in the large N expansion and using the renormalization group. The regime of coupling constants where the…
In the limit of many fermion flavors it is demonstrated that the sextic Gross-Neveu theory in three dimensions displays a line of interacting UV fixed points, characterised by an exactly marginal sextic interaction. We determine the…
We consider intersecting D-brane models which have two dimensional chiral fermions localized at the intersections. At weak coupling, the interactions of these fermions are described by generalized Gross-Neveu models. At strong coupling,…