444 research outputs found

    Gravitational Waves in Relativistic Theory of Gravitation

    Full text link
    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

    Unitarity and the color confinement

    Full text link
    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

    Mass for the graviton

    Get PDF
    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

    Full text link
    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

    Get PDF
    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

    Electron-deuteron scattering in the equal-time formalism: beyond the impulse approximation

    Full text link
    Using a three-dimensional formalism that includes relativistic kinematics, the effects of negative-energy states, approximate boosts of the two-body system, and current conservation, we calculate the electromagnetic form factors of the deuteron up to Q^2 of 4 GeV^2. This is done using a dynamical boost for two-body systems with spin. We first compute form factors in impulse approxmation, but then also add an isoscalar meson-exchange current of pion range that involves the gamma-pi contact operator associated with pseudovector pi-N coupling. We also consider effects of the rho-pi-gamma meson-exchange current. The experimentally measured quantities A, B, and t20 are calculated over the kinematic range probed in recent Jefferson Laboratory experiments. The rho-pi-gamma meson-exchange current provides significant strength in A at large Q^2 and the gamma-pi contact-term exchange current shifts t20, providing good agreement with the JLab data. Relativistic effects and the gamma-pi meson-exchange current do not provide an explanation of the B observable, but the rho-pi-gamma current could help to provide agreement if a nonstandard value is used for the tensor rho-N coupling that enters this contribution.Comment: 15 pages, 10 figures. (v2) Added references on rho-pi-gamma current as well as comparison to recent Novosibirsk data on T20. Implemented \includegraphics in place of \BoxedEPSF. (v3) Modified in order to clarify the nature of the boost we implemented for particles with spin. Other minor changes. Version to be published in Physical Review

    Background Geometry in Gauge Gravitation Theory

    Get PDF
    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→XS\to X such that any spin structure Sh→XS^h\to X associated with a tetrad field hh is a subbundle of the bundle S→XS\to X. In this model, gravitational fields correspond to different tetrad (or metric) fields. (ii) A background tetrad field hh and the associated spin structure ShS^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 hh. One can think of \wt h as being effective tetrad fields. We show that there exist gauge transformations which keep the background tetrad field hh 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

    Full text link
    We review a concept of the Moscow potential (MP) of the NNNN 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 SS- and PP-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

    Full text link
    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
    • …
    corecore