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1.
The variables of a vector meson field are determined within the framework of the Kibble theory as the functions of the metric tensor, affine connection and their derivatives and a system of differential equations is found for the metric tensor and affine connection which is equivalent to the equations of motion of gravitational and vector meson fields.  相似文献   

2.
The field equations of general relativity with electromagnetic stress tensor and zeromass scalar meson field are investigated. The metric coefficients are assumed to be functions of three variables only. It is then shown that, if one assumes a functional relation between some one of the metric coefficients and the electromagnetic potentials, that one can find a solution of the coupled Einstein-Maxwell equations in terms of a solution of the Einstein equations with zeromass scalar meson field as source.  相似文献   

3.
In the usual relativistic mean field(RMF) calculation of stable nuclei, the tensor coupling of ρ meson is not taken into account. It is necessary to clarify thecontribution of the tensor coupling of ρ meson when the RMF is extended to nucleifar from β stability line. The tensor coupling of ρ meson is included and its effectis discussed in the present work.  相似文献   

4.
The thermodynamics of pion-condensed nuclear matter is investigated in a relativistic field theory in the mean field approximation. The conditions of the thermodynamical equilibrium of the system lead to a set of self-consistent equations for the meson field amplitudes and for the wave vector of the pion condensate. It is proved, that in the thermodynamical equilibrium the pressure tensor of isolated, infinite nuclear matter is isotropic at any values of the temperature and chemical potential.  相似文献   

5.
Using a finite form of local field equations some consequences of infinite mass renormalization are studied in a rigorous manner. The method is applied to various models. For pseudoscalar meson-nucleon interaction sufficient conditions are given for the equivalence to a direct Fermi coupling. Confirming a recent result byKroll, Lee, andZumino it is shown that a vector meson field should be proportional to the corresponding current if the bare meson mass is infinite. In the conventional treatment of neutral vector meson theories this causes certain difficulties which are analyzed in detail. In case of two vector fields coupled to the same current it is found that the fields must be proportional provided the bare masses are both infinite. In the Appendix finite local field equations are discussed for the coupling of a neutral vector meson field to the current of a spin 1/2 field.  相似文献   

6.
Mixing of tensor mesons and tensor meson dominance is used to investigate decays of the new particles. We find good agreement of experiment and the quark-gluon mixing scheme of Fritzsch and jackson, which we extend with some modifications to tensor mesons. General features of the scheme have consequences forall meson multiplets, which are in agreement with experiment. Some numerical consequences for additional flavors are worked out.  相似文献   

7.
By the joint assumptions of vector-meson dominance for the electromagnetic current and tensor-meson dominance for the energy-momentum tensor a model for the vector-vector-tensor meson vertex is developed, including also the coupling of two photons to a tensor meson and the coupling of one photon to the vector-tensor meson system. In its simplest possible form the model has no undetermined parameters. Tentatively the vertex is applied to compute a tensor-meson exchange contribution to vector-meson scattering from an unpolarized target, and s-channel helicity conservation is found at large energies.  相似文献   

8.
It is argued that SU(3)-singlet exotic (i.e. built of two or more quark-antiquark pairs) tensor mesons make large contributions to matrix elements of the energy-momentum tensor. An apparent inconsistency between meson dominance models and exchange degeneracy is thereby removed. New predictions about exotic meson couplings follw.  相似文献   

9.
We treat the dynamics of colliding nuclear slabs in a relativistic quantum field theory by using the relativistic mean field approximation. Starting from Walecka's lagrangian, the nucleons are represented by single-particle spinors determined by a Dirac equation that contains a repulsive mean vector meson field and an attractive mean scalar meson field. Both fields satisfy Klein-Gordon equations whose source terms are again determined by the nucleon spinors. The two equal nuclear slabs are translationally invariant in two transverse dimensions and consist of spin and isospin symmetric nuclear matter. By specification of appropriate initial conditions for the collision, we numerically solve the system of coupled Dirac and Klein-Gordon equations for lab energies per nucleon up to 420 MeV. For small energies the results are similar to TDHF results. The time dependence of the density distribution, the mean meson fields, and the damping of the collision are studied. At the highest bombarding energy retardation effects are taken into account.  相似文献   

10.
We report on the phenomenological status of tensor meson dominance. Some new results, mainly concerning hadronic decays of the 2++-meson χ2(3.55) and the heavy lepton τ are also included. Considering experimental errors, we find agreement of tensor meson dominance with experiment.  相似文献   

11.
We present a study of Goldstone boson scattering based on the flavor SU(3) chiral Lagrangian formulated with vector mesons in the tensor field representation. A coupled-channel computation is confronted with the empirical s- and p-wave phase shifts, where good agreement with the data set is obtained up to about 1.2 GeV. There are two relevant free parameters only, the chiral limit value of the pion decay constant and the coupling constant characterizing the decay of the rho meson into a pair of pions. We apply a recently suggested approach that implements constraints from micro-causality and coupled-channel unitarity. Generalized potentials are obtained from the chiral Lagrangian and are expanded in terms of suitably constructed conformal variables. The partial-wave scattering amplitudes are defined as solutions of non-linear integral equations that are solved by means of an N/D ansatz.  相似文献   

12.
Equations of scalar field are constructed by the method of embedding in conformally planar cosmic spaces of the general relativity theory (GRT). The equations are linear relative to the scalar field, which, on the one hand, enables one to regard the permutation function as a four-dimensional radially symmetric solution of the equation of the scalar field, and on the other hand, as a commutator of the wave solutions of the field; in this way the quantization laws are determined for the Fourier amplitudes of the solutions of the equations for the meson field. The wave solution of the scalar meson field is found in the conformally planar GRT space, and the permutation function is obtained as their commutator.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 75–79, March, 1977.  相似文献   

13.
We calculate the energy momentum tensor to orderE 4 in chiral perturbation theory. New terms not present in previous work enter the effective Lagrangian. We describe these and estimate the values of the new coupling constants, using the results of a disperisve analysis of the π andK energy momentum tensors and relying on tensor meson dominance for the spin two component. In addition, we compare our findings with the predictions of known scalar meson dominance models of the conformal anomaly.  相似文献   

14.
《Nuclear Physics A》1996,611(4):442-460
The propagation of a vector meson (ϱ and ω) in dense asymmetric nuclear matter (with the number density of protons and neutrons different) is studied. Of particular interest is the density dependence of the vector meson masses, as also their variation with the asymmetry parameter, mass splitting among the ϱ isospin multiplets and the change of the form of the ϱ meson self-energy or the polarization tensor (IIμν) when the pn symmetry is broken. Contributions of both the Fermi sea and Dirac vacuum have been considered. It is shown that while the density dependent dressing of the vector meson propagator lifts the dispersion characteristics into the region of instability, the Dirac vacuum on the other hand contributes with opposite sign, thereby enhancing the possibility of stable collective modes even for higher values of vector meson momenta. The role of tensor coupling on the dispersion characteristics is also presented.  相似文献   

15.
The dielectric permittivity tensor elements of a rotating cold collisionless plasma spheroid in an external magnetic field with toroidal and axial components are obtained. The effects of inhomogeneity in the densities of charged particles and the initial toroidal velocity on the dielectric permittivity tensor and field equations are investigated. The field components in terms of their toroidal components are calculated and it is shown that the toroidal components of the electric and magnetic fields are coupled by two differential equations. The influence of thermal and collisional effects on the dielectric tensor and field equations in the rotating plasma spheroid are also investigated. In the limiting spherical case, the dielectric tensor of a stationary magnetized collisionless cold plasma sphere is presented.  相似文献   

16.
As is well known the simplest way of formulating the equations for the Yang-Mills gauge fields consists in taking the Lagrangian to be quadratic in the gauge tensor [1 - 5], whereas the application of such an approach to the gravitational field yields equations which are of essentially more complicated structure than the Einstein equations. On the other hand, in the gravitational field theory the Lagrangian can be constructed to be of forms which may be both quadratic and linear in the curvature tensor, whereas the latter possibility is absent in the current gauge field theories. In previous work [6] it has been shown that the Finslerian structure of the space-time gives rise to certain gauge fields provided that the internal symmetries may be regarded as symmetries of a three-dimensional Riemannian space. Continuing this work we show that appropriate equations for these gauge fields can be formulated in both ways, namely on the basis of the quadratic Lagrangian or, if a relevant generalization of the Palatini method is applied, on the basis of a Lagrangian linear in the gauge field strength tensor. The latter possibility proves to result in equations which are similar to the Einstein equations, a distinction being that the Finslerian Cartan curvature tensor rather than the Riemann curvature tensor enters the equations.  相似文献   

17.
18.
We calculate the meson mass spectra in a quark potential model by using the complete Fermi-Breit potential including the terms of orbit-orbit interaction, spin-orbit coupling, and tensor force interaction. We find that these terms give nontrivial contributions to the calculated meson spectra. The orbit-orbit coupling term may lead to an instability of the solution of the Schrodinger equation and should be regularized.  相似文献   

19.
There is a non-linear and covariant electromagnetic analogy for gravity, in which the full Bianchi identities are Maxwell-type equations for the free gravitational field, encoded in the Weyl tensor. This tensor gravito-electromagnetism is based on a covariant generalization of spatial vector algebra and calculus to spatial tensor fields, and includes all non-linear effects from the gravitational field and matter sources. The non-linear vacuum Bianchi equations are invariant under spatial duality rotation of the gravito-electric and gravito-magnetic tensor fields. The super-energy density and super-Poynting vector of the gravitational field are natural duality invariants, and satisfy a super-energy conservation equation.  相似文献   

20.
The three-nucleon system is reconsidered. The Faddeev equations are given leading to a set of integral equations. Solving these integral equations, suitable forms are considered for the nucleon-nucleon interaction. In the bound state of three-nucleon system, the form of the nuclear forces from the nucleon-nucleon interaction is important. In the present calculations, we consider the nuclear forces resulting from the nucleon-nucleon interaction by the exchange of a scalar meson, a pseudoscalar meson, and a massless vector meson. With this different meson exchange nucleon-nucleon interaction, the binding energy of the three-nucleon system is calculated by solving the Faddeev integral equations giving a value of 8.452 MeV.  相似文献   

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