Related papers: Nambu and Compositeness
We investigate a lattice Nambu--Jona-Lasinio model both by the Monte Carlo method and Schwinger-Dyson equations. A comparison allows the discussion of finite size effects and the extrapolation to infinite volume. We pay special attention to…
We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model…
The Nambu--Jona-Lasinio model is chirally symmetric. Addition of a Wilson term explicitly breaks this symmetry and leaves the model with a remaining parity-flavor symmetry. In the approximation of a large number of colors it has been shown…
The phase diagram of the two-dimensional Nambu--Jona-Lasinio model with isospin is explored in the large Nc limit with semiclassical methods. We consider finite temperature and include chemical potentials for all conserved charges. In the…
By adding a small, irrelevant four fermi interaction to the action of noncompact lattice Quantum Electrodynamics (QED), the theory can be simulated with massless quarks in a vacuum free of lattice monopoles. The lattice theory possesses a…
The method of differential regularization is applied to calculate explicitly the one-loop effective potential of a bosonized Nambu--Jona-Lasinio model consisting of scalar and pseudoscalar fields. The regularization scheme independent…
We discuss the only two viable realizations of fermion compositeness described by a calculable relativistic effective field theory consistent with unitarity, crossing symmetry and analyticity: chiral-compositeness vs…
A fermion-boson-type Composite Model is proposed. Elementary fields are only one kind of spin-1/2 and spin-0 {\bf preon}. Both are in the global supersymmetric pair with the common electric charge of e/6 and belong to the fundamental…
We analyze the chiral phase structure of the Nambu--Jona-Lasinio model at finite temperature and density by using the functional renormalization group (FRG). The renormalization group (RG) equation for the fermionic effective potential…
The polarizability of a charged pion is estimated in the framework of the nonlocal chiral quark model of the Nambu--Jona-Lasinio type. Nonlocality is described by quark form factors of the Gaussian type. It is shown that the polarizability…
We explore the features of the $U_A(1)$ and chiral symmetry breaking of the Nambu--Jona-Lasinio model without the Kobayashi-Maskawa-'t Hooft determinant term in the presence of a parallel electromagnetic field. We show that the…
The role of chiral transformations in effective theories modeling Quantum Chromo Dynamics is reviewed. In the context of the Nambu--Jona--Lasinio model the hidden gauge and massive Yang--Mills approaches to vector mesons are demonstrated to…
We present a derivation of the low energy effective action of an extended Nambu Jona-Lasinio (ENJL) model to $O(p^4)$ in the chiral counting. Two alternative scenarios are considered on how the ENJL model could originate as a low energy…
Recent work on QCD-like theories has shown that the addition of adjoint fermions obeying periodic boundary conditions to gauge theories on R^3 X S^1 can lead to a restoration of center symmetry and confinement for sufficiently small…
The connection between QCD, a nonlocal Nambu--Jona-Lasinio type model and the Landau gauge gluon propagator is explored. This two point function is parameterized by a functional form which is compatible with Dyson-Schwinger and lattice QCD…
In search for a composite Higgs boson (techni-dilaton) in the walking technicolor, we present our preliminary results on the first observation of a light flavor-singlet scalar in a candidate theory for the walking technicolor, the Nf=8 QCD,…
The baryon number one soliton of the NJL model is investigated. The Euclidian effective action is regularized using Schwinger's proper time method. Numerical results for the static soliton energy are presented for the cases without and with…
We present our full analysis of the two flavor Nambu--Jona-Lasinio model with $SU(2) \times SU(2)$ chiral symmetry on the four--dimensional hypercubic lattice with naive and Wilson fermions. We find that this model is an excellent toy field…
The properties of the chiral phase transition at finite temperature and chemical potential are investigated within a nonlocal covariant extension of the Nambu-Jona-Lasinio model based on a separable quark-quark interaction. We consider both…
A four-dimensional ${\rm SU}(4)$ confining Yang-Mills field, coupled to a fundamental fermion field and a bi-fundamental scalar field, has excitations with spin-2, but no other quantum numbers. These spin-2 excitations can be light or can…