Unitarity and the color confinement

We discuss how confinement property of QCD results in the rational unitarization scheme and how unitarity saturation leads to appearance of a hadron liquid phase at very high temperatures.Comment: 10 pages, no figire

Gravitational Waves in Relativistic Theory of Gravitation

It is shown that, in the framework of Relativistic Theory of Gravitation with massive graviton, gravitational waves, due to the causality condition, do not bear negative energy flows.Comment: 4 page

Mass for the graviton

Can we give the graviton a mass? Does it even make sense to speak of a massive graviton? In this essay I shall answer these questions in the affirmative. I shall outline an alternative to Einstein Gravity that satisfies the Equivalence Principle and automatically passes all classical weak-field tests (GM/r approx 10^{-6}). It also passes medium-field tests (GM/r approx 1/5), but exhibits radically different strong-field behaviour (GM/r approx 1). Black holes in the usual sense do not exist in this theory, and large-scale cosmology is divorced from the distribution of matter. To do all this we have to sacrifice something: the theory exhibits {*prior geometry*}, and depends on a non-dynamical background metric.Comment: 12 pages, plain LaTeX. Major revisions: (1) Inconsistency in equations of motion fixed. (2) More discussion of the problems associated with quantization. (3) Many more references adde

Masses of heavy baryons in the relativistic quark model

The masses of the ground state heavy baryons consisting of two light (u,d,s) and one heavy (c,b) quarks are calculated in the heavy-quark--light-diquark approximation within the constituent quark model. The light quarks, forming the diquark, and the light diquark in the baryon are treated completely relativistically. The expansion in v/c up to the second order is used only for the heavy (b and c) quarks. The diquark-gluon interaction is taken modified by the form factor describing the light diquark structure in terms of the diquark wave functions. An overall reasonable agreement of the obtained predictions with available experimental data and previous theoretical results is found.Comment: 13 pages, 2 figures, version published in Phys. Rev.

Three-body problem at finite temperature and density

We derive practical three-body equations for the equal-time three-body Green function in matter. Our equations describe both bosons and fermions at finite density and temperature, and take into account all possible two-body sub-processes allowed by the underlying Hamiltonian.Comment: 24 pages, revtex

Background Geometry in Gauge Gravitation Theory

Dirac fermion fields are responsible for spontaneous symmetry breaking in gauge gravitation theory because the spin structure associated with a tetrad field is not preserved under general covariant transformations. Two solutions of this problem can be suggested. (i) There exists the universal spin structure $S\to X$ such that any spin structure $S^h\to X$ associated with a tetrad field $h$ is a subbundle of the bundle $S\to X$. In this model, gravitational fields correspond to different tetrad (or metric) fields. (ii) A background tetrad field $h$ and the associated spin structure $S^h$ are fixed, while gravitational fields are identified with additional tensor fields q^\la{}_\m describing deviations \wt h^\la_a=q^\la{}_\m h^\m_a of $h$. One can think of \wt h as being effective tetrad fields. We show that there exist gauge transformations which keep the background tetrad field $h$ and act on the effective fields by the general covariant transformation law. We come to Logunov's Relativistic Theory of Gravity generalized to dynamic connections and fermion fields.Comment: 12 pages, LaTeX, no figure

Nucleon-nucleon wave function with short-range nodes and high-energy deuteron photodisintegration

We review a concept of the Moscow potential (MP) of the $NN$ interaction. On the basis of this concept we derive by quantum inversion optical partial potentials from the modern partial-wave analysis (PWA) data and deuteron properties. Point-form (PF) relativistic quantum mechanics (RQM) is applied to the two-body deuteron photodisintegration. Calculations of the cross-section angular distributions cover photon energies between 1.1 and 2.5 GeV. Good agreement between our theory and recent experimental data confirms the concept of deep attractive Moscow potential with forbidden $S$- and $P$-states.Comment: 31 pages, 9 figures. typos, extended formalism, review of the Moscow potential model adde

Investigations of the pi N total cross sections at high energies using new FESR: log nu or (log nu)^2

We propose to use rich informations on pi p total cross sections below N= 10 GeV in addition to high-energy data in order to discriminate whether these cross sections increase like log nu or (log nu)^2 at high energies, since it is difficult to discriminate between asymptotic log nu and (log nu)^2 fits from high-energy data alone. A finite-energy sum rule (FESR) which is derived in the spirit of the P' sum rule as well as the n=1 moment FESR have been required to constrain the high-energy parameters. We then searched for the best fit of pi p total cross sections above 70 GeV in terms of high-energy parameters constrained by these two FESR. We can show from this analysis that the (log nu)^2 behaviours is preferred to the log nu behaviours.Comment: to be published in Phys. Rev. D 5 pages, 2 eps figure

The stability of the spectator, Dirac, and Salpeter equations for mesons

Mesons are made of quark-antiquark pairs held together by the strong force. The one channel spectator, Dirac, and Salpeter equations can each be used to model this pairing. We look at cases where the relativistic kernel of these equations corresponds to a time-like vector exchange, a scalar exchange, or a linear combination of the two. Since the model used in this paper describes mesons which cannot decay physically, the equations must describe stable states. We find that this requirement is not always satisfied, and give a complete discussion of the conditions under which the various equations give unphysical, unstable solutions

Weak decays of the B_c meson to B_s and B mesons in the relativistic quark model

Semileptonic and nonleptonic decays of the B_c meson to B_s and B mesons, caused by the c\to s,d quark transitions, are studied in the framework of the relativistic quark model. The heavy quark expansion in inverse powers of the active c and spectator \bar b quark is used to simplify calculations while the final s and d quarks in the B_s and B mesons are treated relativistically. The decay form factors are explicitly expressed through the overlap integrals of the meson wave functions in the whole accessible kinematical range. The obtained results are compared with the predictions of other approaches.Comment: 24 pages, 12 figures, version to appear in Eur. Phys. J.