相关论文: Applications of the nilpotent Dirac state vector
We obtain the spectrum of the Dirac operator on the three-dimensional Heisenberg nilmanifold $\mathcal{M}_3$, and its complete dependence on the metric moduli. As an application, we construct the four-dimensional low-energy effective action…
In a covariant model where constituent quarks and diquarks interact through quark exchange, the Bethe-Salpeter equation in ladder approximation for octet and decuplet baryons is solved. Quark and diquark confinement is thereby effectively…
We investigate the properties of octet and decuplet baryons in a light-front holographic model. By taking into account the effect of nonvanishing quark mass, we obtain the modified light-front wave functions which are applicable at both low…
The formalism of two coupled Dirac equations within constraint instant form dynamics is used to study the nucleon-nucleon interaction. The salient features and the final Schroedinger type equation is given. Explicitly energy dependent…
The weak $\Lambda N\to NN$ transition is studied in the valence quark model approach. The quark component of the two baryon system is described in the quark cluster model and the weak transition potential is calculated by evaluating the…
Semileptonic decays of heavy baryons consisting of one heavy (Q=b,c) and two light (q=u,d,s) quarks are considered in the heavy-quark--light-diquark approximation. The relativistic quasipotential equation is used for obtaining masses and…
Semileptonic decays of doubly heavy baryons are studied in the framework of the relativistic quark model. The doubly heavy baryons are treated in the quark-diquark approximation. The transition amplitudes of heavy diquarks bb and bc going…
The virial and the Hellmann--Feynman theorems for massless Dirac electrons in a solid are derived and analyzed using generalized continuity equations and scaling transformations. Boundary conditions imposed on the wave function in a finite…
Scattering of a 2D Dirac electrons on a rectangular matrix potential barrier is considered using the formalism of spinor transfer matrices. It is shown, in particular, that in the absence of the mass term, the Klein tunneling is not…
Starting from the QCD Lagrangian and taking into account both perturbative and nonperturbative effects, we use the method of vacuum correlators to derive the Dirac equation (rigorously for the Coulomb interaction and heuristically for the…
The present status of the diquark model for exclusive reactions at moderately large momentum transfer is reviewed. That model is a variant of the Brodsky-Lepage approach in which diquarks are considered as quasi-elementary constituents of…
By the large and small wave-function components approach we achieved the nonrela-tivistic limit of the Dirac equation in interaction with an electromagnetic potential in noncommutative phase-space, and we tested the effect of the…
Weak current-induced baryonic form factors at zero recoil are evaluated in the rest frame of the heavy parent baryon using the nonrelativistic quark model. Contrary to previous similar work in the literature, our quark model results do…
The ladder-rainbow truncation of the set of Dyson-Schwinger equations is used to study a variety of electroweak and strong processes involving light mesons. The parameters in the effective interaction are constrained by the chiral…
A relativistic equation is proposed for the bound state of two particles, which is in accord with the boundary condition for the propagation of the negative-energy states and reduces to the (one-body)Dirac equation in the infinite limit of…
Bipolaron energies are calculated as a function of wave vector by a variational method of Gurari appropriate for weak or intermediate coupling strengths, for a model with electron-phonon interactions independent of phonon wave vectors and a…
A simple quark-diquark model of baryons with direct and exchange interactions is constructed. Spectrum and form factors are calculated and compared with experimental data. Advantages and disadvantages of the model are discussed.
The application of quark models to the spectra and strong and electromagnetic couplings of baryons is reviewed. This review focuses on calculations which attempt a global description of the masses and decay properties of baryons, although…
Within an effective Dirac-Weyl theory we solve the scattering problem for massless chiral fermions impinging on a cylindrical time-dependent potential barrier. The set-up we consider can be used to model the electron propagation in a…
In this two part series a chiral confining model of baryons is used to describe low--lying negative parity resonances $N^*$, $\Delta^*$, $\Lambda^*$ and $\Sigma^*$ in the mean field approximation. A physical baryon in this model consists of…