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1.
We consider a model with an abelian gauge symmetry, a Higgs potential involving two scalar fields, and two spinor fields coupled to the scalars through Yukawa couplings. The model accomodates soft violation of charge conjugation, and a domain structure of the universe with two different types of domains, which have identical energy but are governed by different effective lagrangians. The effective lagrangian has complex c-number coefficients that become parts of effective coupling constants, and these are different in the two kinds of domains. In spite of that fact the model neither predicts any domain-dependent effects, nor any particle-antiparticle asymmetries within domains.  相似文献   

2.
We derive the action for nL≥1 chiral spinor multiplets coupled to vector and scalar multiplets. We give the component form of the action, which contains gauge invariant mass terms for the antisymmetric tensors in the spinor superfield and additional Green–Schwarz couplings to vector fields. We observe that supersymmetry provides mass terms for the scalars in the spinor multiplet that do not arise from eliminating an auxiliary field. We construct the dual action by explicitly performing the duality transformations in superspace and give its component form.  相似文献   

3.
A new formulation of thermodynamics for special and general relativistic rotating perfect fluids is developed. Both isolated systems and portions of isolated systems electrically uncharged or charged are treated. Exploiting the symmetry of motion of stationary axisymmetric fluids, the global thermodynamic functions, including total energy and spin, are defined as free scalars, represented by hypersurface integrals of conserved vectors. Local equilibrium parameters such as local temperature and chemical potential are scalar functions. There also exist global equilibrium parameters, global temperature and global chemical potential, which are free scalars. The connection between local and global conditions of thermodynamic equilibrium is made clear and explicit. Thermodynamic potentials are introduced in the context of treating open systems in a relativistically invariant way.  相似文献   

4.
A self-consistent system containing a nonlinear spinor field and a Bianchi type-I (BI) gravitational field is considered in the presence of a viscous fluid and the cosmological constant. Nonlinear terms in the Lagrangian spinor-field appear either due to a self-action, or as a result of interaction with a scalar field. They are given by power functions of the invariants I and J, constructed from the bilinear spinor forms S and P. As far as the viscosity is concerned, it is a function of the energy density ? exhibiting a power-law behavior. Self-consistent solutions of the spinor, scalar, and gravitational field equations are derived. The obtained solutions are expressed in terms of the function τ(t), where τ is the volume scale in the BI-type Universe. A system of equations for τ, H, and ? is derived, where H is the Hubble constant, and ? is the viscous-flow energy. Exact solutions of the system are found for some special choices of the nonlinearity and viscosity. A complete qualitative analysis of the evolution at the boundaries is performed, and numerical solutions are obtained in the most interesting cases. In particular, it is shown that the system has Big Rip type solutions, which is typical for systems containing a phantom matter.  相似文献   

5.
The problem of bound states of the spinor and scalar particles with arbitrary isospin on the back-ground of regular magnetic monopole and dyon solution of theSU(2) gauge system is considered using Newman-Penrose formalism. The explicit general formulas for the energy eigenvalues are obtained which are in agreement with many particular cases described earlier.  相似文献   

6.
The evolution of a homogeneous multicomponent cosmological model with interacting spinor, vector, and scalar fields in the presence of dark energy described by the ideal liquid with the corresponding state equation is considered. The source of the vector and spinor fields is the kinetic energy of the inflation (scalar) field that is modeled by introduction of Lagrangians for the spinor and vector fields interacting with the scalar field through the squared gradient. A system of the dynamic Einstein–Proca–Klein–Fock and ideal liquid equations in the presence of interaction of the cosmological model components is solved. The role of individual components in the process of model evolution is elucidated.  相似文献   

7.
A system of minimally coupled nonlinear spinor and scalar fields within the scope of a Bianchi type-I (BI) cosmological model in the presence of a perfect fluid and a cosmological constant (Λ term) is studied, and solutions to the corresponding field equations are obtained. The problem of initial singularity and the asymptotical isotropization process of the Universe are thoroughly studied. The effect of the Λ term on the character of evolution is analyzed. It is shown that some special choice of spinor field nonlinearity generates a regular solution, but the absence of singularity results in violating the dominant energy condition in the Hawking-Penrose theorem. It is also shown that a positive Λ, which denotes an additional gravitational force in our case, gives rise to an oscillatory or a non-periodic mode of expansion of the Universe depending on the choice of problem parameter. The regular oscillatory mode of expansion violets the dominant energy condition if the spinor field nonlinearity occurs as a result of self-action, whereas, in the case of a linear spinor field or nonlinear one that occurs due to interaction with a scalar field, the dominant condition remains unbroken. A system with time-varying gravitational (G) and cosmological (Λ) constants is also studied to some extent. The introduction of magneto-fluid in the system generates nonhomogeneity in the energy-momentum tensor and can be exactly solved only under some additional condition. Though in this case, we indeed deal with all four known fields, i.e., spinor, scalar, electromagnetic, and gravitational, the over-all picture of evolution remains unchanged.  相似文献   

8.
We consider a system of minimally coupled nonlinear spinor and scalar fields within the scope of a plane-symmetric gravitational field. The gravitational field plays crucial role in the formation of soliton-like solutions, i.e., solutions with limited total energy, spin, and charge. The change of the sign of the scalar field energy density of the system in question realizes physically if and only if the scalar charge does not exceed some critical value. In case of spinor field no such restriction on its parameter occurs. The choice of spinor field nonlinearity leads to the elimination of scalar field contribution to the metric functions, but leaves its contribution to the total energy unaltered. The spinor field is more sensitive to the gravitational field than the scalar field.  相似文献   

9.
The effective action for spinor fields propagating in a time-dependent Kaluza-Klein background geometry is calculated explicitly to one-loop order in an adiabatic approximation. This result is used in a stability analysis of the Candelas-Weinberg model. It is found that the “internal” space (which we choose to be an odd-dimensional sphere SN) is stable against small, uniform oscillations only if the ratio of the number of scalar fields to the number of spinor fields is greater than a certain minimum value.It is also shown that oscillations of the internal space produce conformal gravity waves in the four-dimensional space.  相似文献   

10.
In the past decades, there has been an increasing literature on the presence of an inertial energy cascade in interplanetary space plasma, being interpreted as the signature of Magnetohydrodynamic turbulence (MHD) for both fields and passive scalars. Here, we investigate the passive scalar nature of the solar wind proton density and temperature by looking for scaling features in the mixed-scalar third-order structure functions using measurements on-board the Ulysses spacecraft during two different periods, i.e., an equatorial slow solar wind and a high-latitude fast solar wind, respectively. We find a linear scaling of the mixed third-order structure function as predicted by Yaglom’s law for passive scalars in the case of slow solar wind, while the results for fast solar wind suggest that the mixed fourth-order structure function displays a linear scaling. A simple empirical explanation of the observed difference is proposed and discussed.  相似文献   

11.
The paper consists mainly of two parts. In the first part, we obtain well-defined Killing spinor equations for the low-energy effective action of the bosonic string with the conformal anomaly term. We show that the conformal anomaly term is the only scalar potential that one can add into the action that is consistent with the Killing spinor equations. In the second part, we demonstrate that Kaluza–Klein theory can be gauged so that the Killing spinors are charged under the Kaluza–Klein vector. This gauging process generates a scalar potential with a maximum that gives rise to an AdS spacetime. We also construct solutions of these theories.  相似文献   

12.
Specific effects of the dynamics of (spinor and scalar) wave fields are considered in rotating uniform Gödel-type cosmological models. It is shown that the gravitational interaction of the spinor field can be reduced to the interaction between its pseudovector current and the angular velocity of space-time rotation and is similar to its interaction with the pseudotrace of the space-time twisting. The mean values of energy-momentum tensor of the quantized scalar field in vacuum are calculated in rotating cosmological models and the difference between these values and their mean counterparts in vacuum is determined for Friedman's nonrotating cosmological models.State Education Institute, Yaroslavl'. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 35–38, June, 1992.  相似文献   

13.
We derive the analog of the Cachazo–Svr?ek–Witten (CSW) diagrammatic Feynman rules for four-dimensional Yang–Mills gauge theory coupled to a massive colored scalar. The mass term is shown to give rise to a new tower of vertices in addition to the CSW vertices for massless scalars in non-supersymmetric theories. The rules are derived directly from an action, once through a canonical transformation within light-cone Yang–Mills and once by the construction of a twistor action. The rules are tested against known results in several examples and are used to simplify the proof of on-shell recursion relations for amplitudes with massive scalars.  相似文献   

14.
The sum rules analysis for SU(N) SUSY gluodynamics is presented, concerning scalar, pseudoscalar and spinor channels. The spectrum obtained is characterized by a relatively dense disposition of excitations. The applicability of the effective lagrangian method to the study of resonance properties is thus made doubtful. Some new non-trivial relations between condensates in the SUSY vacuum are also presented.  相似文献   

15.
In this Letter the approximately analytical bound state solutions of the Dirac equation with the Manning-Rosen potential for arbitrary spin-orbit coupling quantum number k are carried out by taking a properly approximate expansion for the spin-orbit coupling term. In the case of exact spin symmetry, the associated two-component spinor wave functions of the Dirac equation for arbitrary spin-orbit quantum number k are presented and the corresponding bound state energy equation is derived. We study briefly two special cases; the general s-wave problem and the equal scalar and vector Manning-Rosen potential.  相似文献   

16.
Owing to the special structure of a five-dimensional Elko spinor, its localization on a brane with codimension one becomes completely different from that of a Dirac spinor. By introducing the coupling between the Elko spinor and the scalar field that can generate the brane, we have two types of localization mechanism for the five-dimensional Elko spinor zero mode on a brane. One is the Yukawa-type coupling, and the other is the non-minimal coupling. In this study, we investigate the localization of the Elko zero mode on de Sitter and Anti-de Sitter thick branes with the two localization mechanisms, respectively. The results show that both the mechanisms can achieve localization. The forms of the scalar coupling function in both localization mechanisms have similar properties, and they play a similar role in localization.  相似文献   

17.
The starting point is the attractive class of composite models where quarks and leptons appear as fermion-scalar bound states (). The aim is to resolve the “naturality” problem associated with fundamental scalars without losing the appealing properties of -type composite models. A systematic construction of such models is given, where the scalar constituents automatically qualify as light dynamical scalars, i.e. as composite (pseudo) Goldstonebosons. A comfortably large class of composite models then results, where all standard “naturality” requirements are satisfied: the quark and lepton masses are kept small through 't Hooft's chiral protection mechanism; the dynamical scalar “constituents” are light and the CP problem of QCD finds an automatic solution. Further characteristics are economy, absence of light exotics, possibility of three generations and elegance of anomaly matching. It is shown that existing attractive models with fundamental scalars can be made “natural” in the sense defined above.  相似文献   

18.
With displacement, time, and force as basic undefined physical quantities, other physical quantities are defined as combinations of two vector quantities and one scalar quantity. Combinations include multiplication and division of vectors by vectors, scalars by vectors, and scalars by scalars. Defined quantities are vectors, scalars or quaternions, depending on directions of vectors in the definitions. Division of a vector by a vector is equivalent to multiplication of vectors divided by a scalar. The unit of a vector (or scalar) is itself a vector (or scalar) quantity. Thesquare meter (a vector) differs from meter 2 (a scalar), and the cubic meter (a scalar) is different frommeter 3 . The characteristics of displacement, time, and force are considered known from experience.  相似文献   

19.
Applying the 1 + 3 formalism we write down the full set of equations governing the structure and the evolution of self-gravitating cylindrically symmetric dissipative fluids with anisotropic stresses, in terms of scalar quantities obtained from the orthogonal splitting of the Riemann tensor (structure scalars), in the context of general relativity. These scalars which have been shown previously (in the spherically symmetric case) to be related to fundamental properties of the fluid distribution, such as: energy density, energy density inhomogeneity, local anisotropy of pressure, dissipative flux, active gravitational mass etc, are shown here to play also a very important role in the dynamics of cylindrically symmetric fluids. It is also shown that in the static case, all possible solutions to Einstein equations may be expressed explicitly through three of these scalars.  相似文献   

20.
D AGBOOLA 《Pramana》2011,76(6):875-885
We present solutions of the Dirac equation with spin symmetry for vector and scalar modified Pöschl–Teller potentials within the framework of an approximation of the centrifugal term. The relativistic energy spectrum is obtained using the Nikiforov–Uvarov method and the two-component spinor wave functions obtained are in terms of the Jacobi polynomials. It is found that there exist only positive energy states for bound states under spin symmetry, and the energy of a level with fixed value of n, increases with increase in dimension of space time and the potential range parameter α.  相似文献   

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