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 $94.576 km \cdot s^{-1} \cdot Mpc^{-1}$).
18218791
Non-Dopplerian cosmological redshift parameters in a model of graviton-dusty universe
Possible effects, which could be caused by a hypothetical super-strong interaction of photons or massive bodies with single gravitons of the graviton background, are considered. If full cosmological redshift magnitudes are caused by the interaction, then the luminosity distance in a flat non-expanding universe as a function of redshift is very similar to the specific function which fits supernova cosmology data by Riess et al (1998 Astron. J. 116 1009). From another side, in this case every massive body, moving slowly relative to the background, would experience a constant acceleration, proportional to the Hubble constant, of the same order as a small additional acceleration of Pioneer 10, 11.
14653034
How to verify the redshift mechanism of low-energy quantum gravity
In the model of low-energy quantum gravity by the author, the redshift mechanism is quantum and local, and it is not connected with any expansion of the Universe. A few possibilities to verify its predictions are considered here: the specialized ground-based laser experiment; a deceleration of massive bodies and the Pioneer anomaly; a non-universal character of the Hubble diagram for soft and hard radiations; galaxy/quasar number counts.
1458405
Low-energy quantum gravity: new challenges for an experiment and observation
Some new challenges for an experiment and observation, which are consequences of the model of low-energy quantum gravity by the author, are considered here. In particular, the property of asymptotic freedom of this model leads to the unexpected consequence: if a black hole arises due to a collapse of a matter with some characteristic mass of particles, its full mass should be restricted from the bottom. For usual baryonic matter, this limit of mass is of the order $10^{7}M_{\odot}$.
119020799
Another possible interpretation of SN 1a data - without kinematics: Comments on the paper astro-ph/0402512 by A. Riess et al
It is shown here that for redshifts $z < 0.5$ the luminosity distance, which is predicted in author's model astro-ph/0005084 v2, fits well supernova observational data of astro-ph/0402512 by A.Riess et al. Discrepancies for higher $z$ would be explained in the model as a result of specific deformation of SN spectra due to a discrete character of photon energy losses. The model does not require any dark energy; it is based on the conjecture that gravitons are super-strong interacting particles fulfilling a flat non-expanding universe.
15798950
Heavy quark limit in the model with confined light quarks and infrared heavy quark propagators
We calculate the weak coupling constants of B and D mesons, and the Isgur‐Wise form factor within the relativistic quark model with confined light quarks and with taking into account the infrared behavior of the heavy quark propagator. We investigate their dependence on the mass difference E=mH−MQ, and the parameter, characterizing the infrared behavior of the heavy quark propagator in the heavy quark limit. It is found that the weak decay constants depend rather strongly on the mass difference E with the infrared parameter ν being fixed. As for the Isgur‐Wise function its E dependence is found weak whereas it depends more strongly on the infrared parameter, leading to the suppression of this function at maximum recoil.
118350677
Cosmological dynamics of fourth-order gravity with a Gauss-Bonnet term
We consider the cosmological dynamics of fourth-order gravity with both f(R) and Φ(G) corrections to the Einstein gravity (G is the Gauss-Bonnet invariant). The particular case for which both terms are equally important on power-law solutions is described. These solutions and their stability are studied using the dynamic system approach. We also discuss the condition of existence and stability of a de Sitter solution in a more general situation of power-law f and Φ.
122225614
Heavy-Quark Limit in a Relativistic Quark-Confinement Model
Abstract. We have studied the weak decay constants and the Isgur-Wise form factors of the B and D mesons in the heavy-quark limit by employing a relativistic 2quark-confinement model. It is an attempt to improve our previous work within the same line of thinking, but by incorporating a couple of novel aspects. First, the infrared behaviour of the heavy quark is considered by modifying its conventional propagator in terms of a single parameter ν. Second, the mass difference between the heavy meson and heavy quark E = mH– MQ has been included. It is found that the weak decay constants depend strongly on this mass difference E with a relatively mild ν dependence. As for the Isgur-Wise function it is controlled more sensitively by the infrared parameter ν, leading to its suppression at maximum meson recoil.
118413560
Heavy-quark symmetries in the light of nonperturbative QCD approaches
We critically review the validity of heavy-quark spin and flavor symmetries in heavy-light decay constants, form factors and effective couplings obtained within a nonperturbative framework, the ingredients of which are all motivated by Dyson-Schwinger equations studies of QCD. Along the way, we make new predictions for two effective nonphysical couplings: g_{DsDK} = 24.1+2.5/-1.6 and g_{BsBK} = 33.3+4.0/-3.7.
119190601
STABLE SUPER-INFLATING COSMOLOGICAL SOLUTIONS IN f(R)-GRAVITY
We consider super-inflating solutions in modified gravity for several popular families of f(R) functions. Using scalar field reformulation of f(R)-gravity we describe how the form of effective scalar field potential can be used for explaining existence of stable super-inflation solutions in the theory under consideration. Several new solutions of this type have been found analytically and checked numerically.