319 research outputs found
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
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.
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
Nucleon-nucleon wave function with short-range nodes and high-energy deuteron photodisintegration
We review a concept of the Moscow potential (MP) of the 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 - and -states.Comment: 31 pages, 9 figures. typos, extended formalism, review of the Moscow
potential model adde
Novel features of diffraction at the LHC
Interest and problems in the studies of diffraction at LHC are highlighted.
Predictions for the global characteristics of proton-proton interactions at the
LHC energy are given. Potential discoveries of the antishadow scattering mode
and diffractive scattering conjugated with high-- jets are discussed.Comment: 10 pages, 7 figures, journal version, 1 figure added, extended
introductio
Hamiltonian anomalies of bound states in QED
The Bound State in QED is described in systematic way by means of nonlocal
irreducible representations of the nonhomogeneous Poincare group and Dirac's
method of quantization. As an example of application of this method we
calculate triangle diagram . We show that
the Hamiltonian approach to Bound State in QED leads to anomaly-type
contribution to creation of pair of parapositronium by two photon.Comment: 12 pages, 2 figures. Proceedings of the conference "Symmetry Methods
in Physics XV", July 12-16, 2011, Dubna, Russi
Soft-core meson-baryon interactions. I. One-hadron-exchange potentials
The Nijmegen soft-core model for the pseudoscalar-meson baryon interaction is
derived, analogous to the Nijmegen NN and YN models. The interaction
Hamiltonians are defined and the resulting amplitudes for one-meson-exchange
and one-baryon-exchange in momentum space are given for the general mass case.
The partial wave projection is carried through and explicit expressions for the
momentum space partial wave meson-baryon potentials are presented.Comment: 25 pages, 2 PostScript figures, revtex4, submitted to Phys. Rev.
Interactions of a boson in the component theory
The amplitudes for boson-boson and fermion-boson interactions are calculated
in the second order of perturbation theory in the Lobachevsky space. An
essential ingredient of the used model is the Weinberg's component
formalism for describing a particle of spin , recently developed
substantially. The boson-boson amplitude is then compared with the two-fermion
amplitude obtained long ago by Skachkov on the ground of the hamiltonian
formulation of quantum field theory on the mass hyperboloid, , proposed by Kadyshevsky. The parametrization of the amplitudes by
means of the momentum transfer in the Lobachevsky space leads to same spin
structures in the expressions of matrices for the fermion and the boson
cases. However, certain differences are found. Possible physical applications
are discussed.Comment: REVTeX 3.0 file. 12pp. Substantially revised version of IFUNAM
preprints FT-93-24, FT-93-3
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.
Relativistic quasipotential equations with u-channel exchange interactions
Various quasipotential two-body scattering equations are studied at the
one-loop level for the case of - and -channel exchange potentials. We
find that the quasipotential equations devised to satisfy the one-body limit
for the -channel exchange potential can be in large disagreement with the
field-theoretical prediction in the case of -channel exchange interactions.
Within the spectator model, the description of the -channel case improves if
another choice of the spectator particle is made. Since the appropriate choice
of the spectator depends strongly on the type of interaction used, one faces a
problem when both types of interaction are contained in the potential.
Equal-time formulations are presented, which, in the light-heavy particle
system corresponding to the mass situation of the system, approximate
in a reasonable way the field-theoretical result for both types of
interactions.Comment: Revtex, 20 pages, 12 PostScript figures, to appear in Phys. Rev.
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