Related papers: The A5 and the pion field
The Lagrangian of non-Abelian tensor gauge fields describes the interaction of the Yang-Mills and massless tensor bosons of increasing helicities. We have found a metric-independent gauge invariant density which is a four-dimensional analog…
A higher spin field theory on AdS(4) possesses a conformal field theory on the boundary R(3) which can be identified with the critical O(N) sigma model of O(N) invariant fields only. The notions of quasiprimary and secondary fields can be…
The electromagnetic form factor of the pion is obtained using a particular realization of QCD in the large $N_c$ limit, which sums up the infinite number of zero-width resonances to yield an Euler's Beta function of the Veneziano type. This…
We develop a formalism to calculate form factor and charge density distribution of pion in the chiral limit using the holographic dual model of QCD with hard-wall cutoff. We introduce two conjugate pion wave functions and present analytic…
We discuss electro-magnetic and weak production of pions on nucleons and show how results of experiments and their interpretation in terms of chiral quark models with explicit meson degrees of freedom combine to reveal the ground-state…
Domain model of QCD allows for description of wide range of meson observables, dynamical chiral symmetry breaking, and resolution of $U_A(1)$ and strong $CP$ problems. The purpose of the present study is transition form-factor of neutral…
In order to understand the so-called decoupling solution for gluon and ghost propagators in QCD, we give a nonperturbative construction of a massive vector field describing a non-Abelian massive spin-one particle, which has the correct…
We study phenomenological aspects of the holographic model of chiral symmetry breaking recently introduced by Kuperstein and Sonnenschein (KS). As a first step, we calculate the spectrum of vector and axial-vector mesons in the KS model. We…
We introduce a class of composite axion models that provide a natural solution to the strong CP problem, and possibly account for the observed dark matter abundance. The QCD axion arises as a composite Nambu-Goldstone boson (NGB) from the…
We analyze the vacuum structure of N=2, SU(2) QCD with massive quark hypermultiplets, once supersymmetry is softly broken down to N=0 with dilaton and mass spurions. We give general expressions for the low energy couplings of the effective…
These lectures provide an introduction to the behavior of strongly-coupled supersymmetric gauge theories. After a discussion of the effective Lagrangian in nonsupersymmetric and supersymmetric field theories, I analyze the qualitative…
Sum rules for products of two, three and four QCD currents are derived using chiral symmetry at infinite momentum in the large-N limit. These exact relations among meson decay constants, axialvector couplings and masses determine the…
A quadratic action in even Grassmann variables with the quantum numbers of the pions has been studied. It includes the $\sigma$-field in order to be invariant under SU(2)_L times SU(2)_R transformations over the quarks. This action exhibits…
In the present paper we discuss various aspects of the 't Hooft model for two-dimensional QCD in the limit of infinite number of colours in the Coulomb gauge. The properties of mesonic excitations are addressed, with special attention paid…
If a global chiral symmetry is explicitly broken by anomalies in nonabelian gauge theories, a pseudo Nambu-Goldstone boson (axion) associated with a spontaneous breakdown of such a global symmetry acquires a mass through nonperturbative…
We use dispersive techniques to address the behavior of the pion form factor as $Q^2 \to \infty$ and $Q^2 \to 0$. We perform the matching with the constraints of perturbative QCD and chiral perturbation theory in the high energy and low…
Mechanism for generation of vector meson resonances is studied in the framework of QCD Dyson-Schwinger equations, which are defined and actually solved in Minkowski space. It is suggested that the timelike pion form factor is generated by…
We suggest an extension of the Yang-Mills theory which includes non-Abelian tensor gauge fields. The invariant Lagrangian is quadratic in the field strength tensors and describes interaction of charged tensor gauge bosons of arbitrary large…
We analyze the vacuum structure of an eight-dimensional non-abelian gauge theory with a compactified four-dimensional torus as the extra dimensions. As a non-trivial background configuration of the gauge field of an $SU(n)$ gauge group, we…
It is shown that a chiral SU(2) model can break Lorentz symmetry spontaneously at the Lagrangian level when gauge bosons become massive. This model seems to propose the principles and conceptual foundations leading to a unified picture of…