17217393
Superspace without torsion and the composite fundamental fermions
(N=2)-superspace without torsion is described, which is equivalent to an 8-space with a discrete internal subspace. A number and a character of ties determine now an internal symmetry group, while in the supersymmetrical models this one is determined by an extension degree N. Such a model can be constructed for no less than 4 generations of the two-component fundamental fermions. Analogues of the Higgs fields appear in the model naturally after transition to the Grassmannian extra coordinates. The connection between discrete and continues internal symmetries of the model is discussed. If one considers gravity as embedding the curved 4-space into a 12-dimensional flat space, a U(1)-symmetry appears transformations of which should be connected with the ones of SU(2)-group. If super-strong interacting gravitons are constituents of the composite fermions, all this may open us another way to unify the known interactions. The main feature of this new approach may be the external see of gravitons underlying an internal structure of particles; the lack of any divergencies would be due the Planckian spectrum of external gravitons.
18867033
A quantum gravitational model of redshifts
The main features of an alternative model of redshifts are described here. The model is based on conjectures about an existence of the graviton background with the Planckian spectrum and a super-strong character of quantum gravitational interaction. This model is connected with the assumed quantum mechanism of gravity. A behavior of two theoretical functions of a redshift $z$ in this model - the geometrical distance $r(z)$ and the luminosity distance $D_{L}(z)$ - and an existence of two different cosmological horizons for any observer are discussed.
16705419
A Fine quantum mechanism of classical gravity
It is shown that screening the background of super-strong interacting gravitons ensures the Newtonian attraction, if a part of single gravitons is pairing and graviton pairs are destructed by collisions with a body. If the considered quantum mechanism of classical gravity is realized in the nature, than an existence of black holes contradicts to the equivalence principle. In such the model, Newton's constant is proportional to $H^{2}/T^{4},$ where $H$ is the Hubble constant, $T$ is an equivalent temperature of the graviton background. The estimate of the Hubble constant is obtained for the Newtonian limit: $H=3.026 \cdot 10^{-18} s^{-1}$ (or $94.576 km \cdot s^{-1} \cdot Mpc^{-1}$).
16526170
Small effects of low-energy quantum gravity
Small effects of quantum gravity on the scale $\sim 10^{-3} eV$ and their cosmological consequences are discussed and compared with observations of supernovae 1a, gamma-ray bursts and galaxies.
16422963
May gravitons be super-strong interacting particles?
A scheme, in which gravitons are super-strong interacting, is described. The graviton background with the Planckian spectrum and a small effective temperature is considered as a reservoir of gravitons. A cross-section of interaction of a graviton with any particle is assumed to be a bilinear function of its energies. Any pair of bodies are attracting not due to an exchange with its own gravitons, but due to a pressure of external gravitons of this background. A graviton pairing is necessary to obtain classical gravity. Any divergencies are not possible in such the model because of natural smooth cut-offs of the graviton spectrum from both sides. Some cosmological consequences of this scheme are discussed, too. Also it is shown here that the main conjecture of this approach may be verified at present on the Earth.
14410547
Model of graviton-dusty universe
Primary features of a new cosmological model, which is based on conjectures about an existence of the graviton background and superstrong gravitational quantum interaction, are considered. An expansion of the universe is impossible in such the model because of deceleration of massive objects by the graviton background, which is similar to the one for the NASA deep space probes Pioneer 10, 11. Redshifts of remote objects are caused in the model by interaction of photons with the graviton background, and the Hubble constant depends on an intensity of interaction and an equivalent temperature of the graviton background. Virtual massive gravitons would be dark matter particles. They transfer energy, lost by luminous matter radiation, which in a final stage may be collected with black holes and other massive objects.
18648204
Decay Constants and Semileptonic Form Factors of Pseudoscalar Mesons 1
AbstractA relativistic constituent quark model is adopted to give an uniﬁed description of the leptonic andsemileptonic decays of pseudoscalar mesons (π, K, D, D s , B, B s ). The calculated leptonic decayconstants and form factors are found to be in good agreement with available experimental data andthe results of other approaches. Eventually, the model is found to reproduce the scaling behavioursof spin-ﬂavor symmetry in the heavy-quark limit. 1 Introduction Semileptonic decays of pseudoscalar mesons allow to evaluate the elements of the Cabibbo–Kobayashi–Maskawa (CKM) matrix, which are fundamental parameters of the Standard Model. The decay K → πeνprovides the most accurate determination of V us , the semileptonic decays of D and B mesons, D →K(K ∗ )lν, B → D(D ∗ )lν and B → π(ρ)lν, can be used to determine |V cs |, |V cb | and |V ub |, respectively.This program can be performed if the non-perturbative QCD eﬀects, which are parameterized by theform factors, are known. Up to now, these form factors cannot be evaluated from ﬁrst principles, thusmodels, more or less connected with QCD, are usually considered for this purpose. Here we discuss arelativistic quark model [1], previously used to study the baryon form factors [2].This model is based on an eﬀective Lagrangiandescribingthe coupling ofmesons with their constituentquarks. The physical processes are described by the one-loop quark diagrams and meson-quark verticesrelated to the Bethe-Salpeter amplitudes. In principle, the vertex functions and quark propagatorsshouldbe given by the Bethe-Salpeter and Dyson-Schwinger equations, respectively. This kind of analysis isprovided by the Dyson-Schwinger Equation (DSE) studies [3] and an uniﬁed description of light andheavy meson observables was carried out in [4, 5]. Here, instead, we use free propagators for constituentquarks and consider a Gaussian vertex function as Bethe-Salpeter conﬁning function. The adjustableparameters, the widths of Bethe-Salpeter amplitudes in momentum space, and the constituent quarkmasses, are determined from the best ﬁt of available experimental data and some lattice simulations.Our results are in good agreement with experimental data and other approaches. We also reproduce thespin-ﬂavor symmetry relations and scaling for leptonic decay constants and semileptonic form factors inthe heavy-quark limit [6].An approach similar to the one presented here, can be found in [7]. That model is based on meson-quark interactions, so the mesonic transition amplitudes are described by diagrams with heavy mesonsattached to quark loops. The free propagator has been used for light quarks, while the quark propagatorobtained in the heavy-quark limit has been adopted for heavy quarks.
116517338
The Low Energy Physics of Pion in the Relativistic Model with a Separable Interaction
A Lagrangian formulation of the Nambu-Jona-Lasinio model with separable interaction is given. The electromagnetic interaction is introduced in a non-minimal way to the nonlocal quark current. Various choices of the vertex form factors characterizing the composite structure of mesons and baryon are investigated. W’e find that the physical observables depend very weakly on form factor shapes. PACS. 12.39.Fe - Chiral Lagrangians.
119015787
Magnetic moments of heavy baryons in the relativistic three-quark model
The magnetic moments of ground state single, double and triple heavy baryons containing charm or bottom quarks are calculated in a relativistic three-quark model, which, in the heavy-quark limit, is consistent with heavy-quark effective theory and heavy hadron chiral perturbation theory. The internal quark structure of baryons is modeled by baryonic three-quark currents with a spin-flavor structure patterned according to standard covariant baryonic wave functions and currents used in QCD sum rule calculations.
126090240
pi pi SCATTERING IN THE QUARK CONFINEMENT MODEL. PHASE SHIFTS
118854738
Form factors for semileptonic, nonleptonic and rare B (Bs) meson decays
We provide new values for the model parameters of the covariant constituent quark model (with built–in infrared confinement) in the meson sector by a fit to the leptonic decay constants and a number of electromagnetic decays. We then evaluate, in a parameter-free way, the form factors of the B(Bs) ! P(V ) transitions in the full kinematical region of momentum transfer. As an application of our results we calculate the widths of the nonleptonic Bs-decays into Ds D + , D � s D + s +D s D � + s