493,658 research outputs found

    Multidimensional Dynamical Systems Accepting the Normal Shift

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    The dynamical systems of the form \ddot\bold r=\bold F (\bold r,\dot\bold r) in Rn\Bbb R^n accepting the normal shift are considered. The concept of weak normality for them is introduced. The partial differential equations for the force field \bold F(\bold r,\dot\bold r) of the dynamical systems with weak and complete normality are derived.Comment: AMS-TeX, ver. 2.1, IBM AT-386, size 16K (ASCII), short versio

    The matrix Hamiltonian for hadrons and the role of negative-energy components

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    The world-line (Fock-Feynman-Schwinger) representation is used for quarks in arbitrary (vacuum and valence gluon) field to construct the relativistic Hamiltonian. After averaging the Green's function of the white qqˉq\bar q system over gluon fields one obtains the relativistic Hamiltonian, which is matrix in spin indices and contains both positive and negative quark energies. The role of the latter is studied in the example of the heavy-light meson and the standard einbein technic is extended to the case of the matrix Hamiltonian. Comparison with the Dirac equation shows a good agreement of the results. For arbitrary qqˉq\bar q system the nondiagonal matrix Hamiltonian components are calculated through hyperfine interaction terms. A general discussion of the role of negative energy components is given in conclusion.Comment: 29 pages, no figure

    Analytic calculation of field-strength correlators

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    Field correlators are expressed using background field formalism through the gluelump Green's functions. The latter are obtained in the path integral and Hamiltonian formalism. As a result behaviour of field correlators is obtained at small and large distances both for perturbative and nonperturbative parts. The latter decay exponentially at large distances and are finite at x=0, in agreement with OPE and lattice data.Comment: 28 pages, no figures; new material added, misprints correcte

    Induced quantum numbers of a magnetic monopole at finite temperature

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    A Dirac electron field is quantized in the background of a Dirac magnetic monopole, and the phenomenon of induced quantum numbers in this system is analyzed. We show that, in addition to electric charge, also squares of orbital angular momentum, spin, and total angular momentum are induced. The functional dependence of these quantities on the temperature and the CP-violating vacuum angle is determined. Thermal quadratic fluctuations of charge and squared total angular momentum, as well as the correlation between them and their correlations with squared orbital angular momentum and squared spin, are examined. We find the conditions when charge and squared total angular momentum at zero temperature are sharp quantum observables rather than mere quantum averages.Comment: 24 pages, minor grammatical changes, journal versio

    Contextual approach to quantum mechanics and the theory of the fundamental prespace

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    We constructed a Hilbert space representation of a contextual Kolmogorov model. This representation is based on two fundamental observables -- in the standard quantum model these are position and momentum observables. This representation has all distinguishing features of the quantum model. Thus in spite all ``No-Go'' theorems (e.g., von Neumann, Kochen and Specker,..., Bell) we found the realist basis for quantum mechanics. Our representation is not standard model with hidden variables. In particular, this is not a reduction of quantum model to the classical one. Moreover, we see that such a reduction is even in principle impossible. This impossibility is not a consequence of a mathematical theorem but it follows from the physical structure of the model. By our model quantum states are very rough images of domains in the space of fundamental parameters - PRESPACE. Those domains represent complexes of physical conditions. By our model both classical and quantum physics describe REDUCTION of PRESPACE-INFORMATION. Quantum mechanics is not complete. In particular, there are prespace contexts which can be represented only by a so called hyperbolic quantum model. We predict violations of the Heisenberg's uncertainty principle and existence of dispersion free states.Comment: Plenary talk at Conference "Quantum Theory: Reconsideration of Foundations-2", Vaxjo, 1-6 June, 200

    The coupled-channel analysis of the D and D_s mesons

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    The shift of the p-wave DsD_s meson mass due to coupling to the DK channel is calculated without fitting parameters using the chiral Lagrangian. As a result the original QqˉQ\bar q mass 2.490 MeV generically calculated in the relativistic quark models is shifted down to the experimental value 2317 MeV. With the same Lagrangian the shift of the radial excited 11^- level is much smaller, while the total width Γ>100\Gamma > 100 MeV and the width ratio is in contradiction with the D(2632)D^*(2632) state observed by SELEX group.Comment: 9 pages, 2 figure

    Low-frequency internal friction (LFIF) as express-method for identification of cryocrystals in pores of the solids

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    We show that studying of low-frequency internal friction (LFIF) of solid samples at low temperatures allows determining the presence of various gases absorbed, for some reasons, in pores and caverns of the solids. The gases come over to a solid state (cryocrystals) and exist in the pores under corresponding thermodynamic conditions giving an additional contribution to the LFIF spectra. The spectra reflect the special points of the gases (temperatures of melting or phase transitions). This information gives a real opportunity for identification of gas in the matrix, i.e. the studied solids. This may be of great importance for investigations of cosmic or geological samples, for instance, asteroids, meteorites, rock formations, etc. The LFIF method allows identification of gas media surrounding the studied sample.Comment: 14 pages, 8 figures, 39 ref
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