1,616 research outputs found

    Wilsonian effective action for SU(2) Yang-Mills theory with Cho-Faddeev-Niemi-Shabanov decomposition

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    The Cho-Faddeev-Niemi-Shabanov decomposition of the SU(2) Yang-Mills field is employed for the calculation of the corresponding Wilsonian effective action to one-loop order with covariant gauge fixing. The generation of a mass scale is observed, and the flow of the marginal couplings is studied. Our results indicate that higher-derivative terms of the color-unit-vector n\mathbf{n} field are necessary for the description of topologically stable knotlike solitons which have been conjectured to be the large-distance degrees of freedom.Comment: 15 pages, no figures, v2: minor improvements, one reference added, version to appear in PR

    Weyl group, CP and the kink-like field configurations in the effective SU(3) gauge theory

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    Effective Lagrangian for pure Yang-Mills gauge fields invariant under the standard space-time and local gauge SU(3) transformations is considered. It is demonstrated that a set of twelve degenerated minima exists as soon as a nonzero gluon condensate is postulated. The minima are connected to each other by the parity transformations and Weyl group transformations associated with the color su(3) algebra. The presence of degenerated discrete minima in the effective potential leads to the solutions of the effective Euclidean equations of motion in the form of the kink-like gauge field configurations interpolating between different minima. Spectrum of charged scalar field in the kink background is discussed.Comment: 10 pages, 1 figure, added references for sections 1 and

    Yang-Mills Fields Quantization in the Factor Space

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    The perturbation theory over inverse interaction constant 1/g1/g is constructed for Yang-Mills theory. It is shown that the new perturbation theory is free from the gauge ghosts and Gribov's ambiguities, each order over 1/g1/g presents the gauge-invariant quantity. It is remarkable that offered perturbation theory did not contain divergences, at least in the vector fields sector, and no renormalization procedure is necessary for it.Comment: 27 pages, Latex, no figure

    Impact of Heat Resources on Rice Productivity in the Sarpinsky Lowland

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    The possibility of rice cultivation in the northern areas of rice sowing is determined by the sum of effective air temperatures (Σt ≥ 15 ∘C) over the growing season and its distribution over the vegetation phases of the plants. A long-term statistical and correlation analysis of rice productivity depending on the thermal resources of the Sarpinsky lowland at the Maliye Derbeta meteorological station for the period from 1964 to 2018 (correlation coefficient r = 0.68) is given. It is established that the sum of effective air temperatures varies from 3140.2 to 3999.7 ∘C, while the average annual value is 2820 ∘C. The highest yield (more than 5 t/ha) of rice grains is formed in years with the sum of effective temperatures over 3000 ∘C. The fluctuations of air temperature and their influence on the production process, and the yield of rice grains are analyzed, the results of which can be used as source data in modeling climate change scenarios and predicting rice grain production. The optimal amounts of effective air temperatures for the period April-September, ensuring the realization of the potential productivity of rice in the Sarpinsky lowland conditions, are determined

    Lagrangian and Hamiltonian Formalism on a Quantum Plane

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    We examine the problem of defining Lagrangian and Hamiltonian mechanics for a particle moving on a quantum plane Qq,pQ_{q,p}. For Lagrangian mechanics, we first define a tangent quantum plane TQq,pTQ_{q,p} spanned by noncommuting particle coordinates and velocities. Using techniques similar to those of Wess and Zumino, we construct two different differential calculi on TQq,pTQ_{q,p}. These two differential calculi can in principle give rise to two different particle dynamics, starting from a single Lagrangian. For Hamiltonian mechanics, we define a phase space TQq,pT^*Q_{q,p} spanned by noncommuting particle coordinates and momenta. The commutation relations for the momenta can be determined only after knowing their functional dependence on coordinates and velocities. Thus these commutation relations, as well as the differential calculus on TQq,pT^*Q_{q,p}, depend on the initial choice of Lagrangian. We obtain the deformed Hamilton's equations of motion and the deformed Poisson brackets, and their definitions also depend on our initial choice of Lagrangian. We illustrate these ideas for two sample Lagrangians. The first system we examine corresponds to that of a nonrelativistic particle in a scalar potential. The other Lagrangian we consider is first order in time derivative

    Dynamics in a noncommutative phase space

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    Dynamics has been generalized to a noncommutative phase space. The noncommuting phase space is taken to be invariant under the quantum group GLq,p(2)GL_{q,p}(2). The qq-deformed differential calculus on the phase space is formulated and using this, both the Hamiltonian and Lagrangian forms of dynamics have been constructed. In contrast to earlier forms of qq-dynamics, our formalism has the advantage of preserving the conventional symmetries such as rotational or Lorentz invariance.Comment: LaTeX-twice, 16 page

    Gribov Problem for Gauge Theories: a Pedagogical Introduction

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    The functional-integral quantization of non-Abelian gauge theories is affected by the Gribov problem at non-perturbative level: the requirement of preserving the supplementary conditions under gauge transformations leads to a non-linear differential equation, and the various solutions of such a non-linear equation represent different gauge configurations known as Gribov copies. Their occurrence (lack of global cross-sections from the point of view of differential geometry) is called Gribov ambiguity, and is here presented within the framework of a global approach to quantum field theory. We first give a simple (standard) example for the SU(2) group and spherically symmetric potentials, then we discuss this phenomenon in general relativity, and recent developments, including lattice calculations.Comment: 24 pages, Revtex 4. In the revised version, a statement has been amended on page 11, and References 14, 16 and 27 have been improve

    The Inverse Variational Problem for Autoparallels

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    We study the problem of the existence of a local quantum scalar field theory in a general affine metric space that in the semiclassical approximation would lead to the autoparallel motion of wave packets, thus providing a deviation of the spinless particle trajectory from the geodesics in the presence of torsion. The problem is shown to be equivalent to the inverse problem of the calculus of variations for the autoparallel motion with additional conditions that the action (if it exists) has to be invariant under time reparametrizations and general coordinate transformations, while depending analytically on the torsion tensor. The problem is proved to have no solution for a generic torsion in four-dimensional spacetime. A solution exists only if the contracted torsion tensor is a gradient of a scalar field. The corresponding field theory describes coupling of matter to the dilaton field.Comment: 13 pages, plain Latex, no figure

    Phase spaces related to standard classical rr-matrices

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    Fundamental representations of real simple Poisson Lie groups are Poisson actions with a suitable choice of the Poisson structure on the underlying (real) vector space. We study these (mostly quadratic) Poisson structures and corresponding phase spaces (symplectic groupoids).Comment: 20 pages, LaTeX, no figure
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