Related papers: Solutions of Bethe-Salpter equations in QED3
We perform a 3D reduction of the two-fermion Bethe-Salpeter equation based on Sazdjian's explicitly covariant propagator, combined with a covariant substitute of the projector on the positive-energy free states. We use this combination in…
We estimate the QCD effective charge $\alpha_s$ in the low-energy region by exploiting the conventional meson spectrum within a relativistic quantum-field model based on analytic confinement. The ladder Bethe-Salpeter equation is solved for…
A large class of scalar-tensor theories of gravity exhibit a screening mechanism that dynamically suppresses fifth forces in the Solar system and local laboratory experiments. Technically, at the scalar field equation level, this usually…
The spectrum of light bound states in an SU(2) gauge theory with two flavors of fundamentally charged fermions is investigated by solving the Bethe-Salpeter equations in the respective channels within a 3PI-type (i.e., beyond…
The Bethe-Salpeter equation (BSE) is currently the state of the art in the description of neutral electron excitations in both solids and large finite systems. It is capable of accurately treating charge-transfer excitations that present…
We solve the Bethe-Salpeter equation (BSE) for a system of a heavy quark-antiquark pair interacting with a Poincare invariant generalization of screened linear confining potential. In order to get reliable description the Lorentz scalar…
We investigate cosmological solutions of the chameleon model with a non-minimal coupling between the matter and the scalar field through a conformal factor with gravitational strength. By considering the spatially flat FLRW metric and the…
The color excitations of interacting fermions carrying an $SU(3)$ color and $U(N_f)$ flavor index in one spatial dimension are studied in the framework of a perturbed $SU(3)_{N_f}$ Wess-Zumino-Novikov-Witten model. Using Bethe ansatz…
With the aim of a further investigation of the nonperturbative Hamiltonian approach in gauge field theories, the mass spectrum of QED-2 is calculated numerically by using the corrected Hamiltonian that was constructed previously for this…
Independent of assumptions about the form of the quark-quark scattering kernel, K, we derive the explicit relation between the flavour-nonsinglet pseudoscalar meson Bethe-Salpeter amplitude, Gamma_H, and the dressed-quark propagator in the…
We give a derivation of the particle-hole RPA equations for an interacting multi-fermion system by applying the instantaneous approximation to the amputated two-fermion propagator of the system. In relativistic field theory the same…
The problem of a fermion subject to a general mixing of vector and scalar potentials in a two-dimensional world is mapped into a Sturm-Liouville problem. Isolated bounded solutions are also searched. For the specific case of an inversely…
The difficulties that typically prevent numerical solutions from being obtained to finite-energy, two-body, bound-state Bethe-Salpeter equations can often be overcome by expanding solutions in terms of basis functions that obey the boundary…
In relativistic frameworks, given by the Bethe-Salpeter and light-front bound state equations, the binding energies of system of three scalar particles interacting by scalar exchange particles are calculated. In contrast to two-body…
Based on the hard-thermal-loop resummed improved ladder Dyson-Schwinger quation for the fermion mass function, we study how we can get the gauge invariant solution in the sense it satisfies the Ward identity. Properties of the…
We have constructed nonrelativistic fermion and scalar field theories coupled to a Maxwell-Chern-Simons gauge field which admit static multi-vortex solutions. This is achieved by introducing a magnetic coupling term in addition to the usual…
We present preliminary lattice results for the nonperturbative tensor structure of the vector and axial-vector quark-antiquark vertices in QCD. Our lattice calculations are for $N_f=2$ mass-degenerate Wilson fermion flavors whose quark mass…
The ladder Bethe-Salpeter solution for the dressed photon-quark vertex is used to study the low-momentum behavior of the pion electromagnetic and the $\gamma^\star \pi^0 \gamma$ transition form factors. With model parameters previously…
The effect of quark-gluon vertex dressing on the ground state masses of the u/d-quark pseudoscalar, vector and axialvector mesons is considered with the Dyson-Schwinger equations. This extends the ladder-rainbow Bethe-Salpeter kernel to…
The light scalar meson spectrum is studied using the improved ladder QCD with the UA(1) breaking Kobayashi-Maskawa-'t Hooft interaction by solving the Schwinger-Dyson and Bethe-Salpeter equations. The dynamically generated…