36,365 research outputs found

    Analytic, Non-Perturbative, Gauge-invariant QCD: Nucleon Scattering and Binding Potentials

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    Removal of the quenched approximation in the mechanism which produced an analytic estimate of quark-binding potentials, along with a reasonable conjecture of the color structure of the nucleon formed by such a binding potential, is shown to generate an effective, nucleon scattering and binding potential. The mass-scale factor on the order of the pion mass, previously introduced to define transverse imprecision of quark coordinates, is again used, while the strength of the potential is proportional to the square of a renormalized QCD coupling constant. The potential so derived does not include corrections due to spin, angular momentum, nucleon structure, and electroweak interactions; rather, it is qualitative in nature, showing how Nuclear Physics can arise from fundamental QCD.Comment: 25 pages, 3 figures in REVTeX. The fifth of a series on Non-Perturbative QCD (Eur. Phys. J. C65, 395 (2010) or arXiv:0903.2644 [hep-th], arXiv:1003.2936 [hep-th], arXiv:1103.4179 [hep-th] and arXiv:1104.4663 [hep-th].

    Non-abelian Eikonals

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    A functional formulation and partial solution is given of the non-abelian eikonal problem associated with the exchange of non-interacting, charged or colored bosons between a pair of fermions, in the large ss/small tt limit. A simple, functional ``contiguity" prescription is devised for extracting those terms which exponentiate, and appear to generate the leading, high-energy behavior of each perturbative order of this simplest non-abelian eikonal function; the lowest non-trivial order agrees with the corresponding SU(N) perturbative amplitude, while higher-order contributions to this eikonal generate an ``effective Reggeization" of the exchanged bosons, resembling previous results for the perturbative amplitude. One exact and several approximate examples are given, including an application to self-energy radiative corrections. In particular, for this class of graphs and to all orders in the coupling, we calculate the leading-log eikonal for SU(2). Based on this result, we conjecture the form of the eikonal scattering amplitude for SU(N).Comment: 19 pages, late

    The One Loop Effective Action of QED for a General Class of Electric Fields

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    We compute the effective action of QED at one loop order for an electric field which points in the z^\hat{z} direction and depends arbitrarily upon the light cone time coordinate, x+=(x0+x3)/2x^+ = (x^0 + x^3)/\sqrt{2}. This calculation generalizes Schwinger's formula for the vacuum persistence probability in the presence of a constant electric field.Comment: 9 pages, LaTeX 2 epsilo

    A New Approach to Analytic, Non-Perturbative and Gauge-Invariant QCD

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    Following a previous calculation of quark scattering in eikonal approximation, this paper presents a new, analytic and rigorous approach to the calculation of QCD phenomena. In this formulation a basic distinction between the conventional "idealistic" description of QCD and a more "realistic" description is brought into focus by a non-perturbative, gauge-invariant evaluation of the Schwinger solution for the QCD generating functional in terms of the exact Fradkin representations of the Green's functional and the vacuum functional. Because quarks exist asymptotically only in bound states, their transverse coordinates can never be measured with arbitrary precision; the non-perturbative neglect of this statement leads to obstructions that are easily corrected by invoking in the basic Lagrangian a probability amplitude which describes such transverse imprecision. The second result of this non-perturbative analysis is the appearance of a new and simplifying output called "Effective Locality", in which the interactions between quarks by the exchange of a "gluon bundle" - which "bundle" contains an infinite number of gluons, including cubic and quartic gluon interactions - display an exact locality property that reduces the several functional integrals of the formulation down to a set of ordinary integrals. It should be emphasized that "non-perturbative" here refers to the effective summation of all gluons between a pair of quark lines, but does not (yet) include a summation over all closed-quark loops which are tied by gluon-bundle exchange to the rest of the "Bundle Diagram". As an example of the power of these methods we offer as a first analytic calculation the quark-antiquark binding potential of a pion, and the corresponding three-quark binding potential of a nucleon, obtained in a simple way from relevant eikonal scattering approximations.Comment: 38 pages, 3 figures in REVTeX. Collections of follow-on work of Eur. Phys. J. C65, pp. 395-411 (2010). arXiv admin note: text overlap with arXiv:1103.4179, arXiv:1104.4663, arXiv:1003.293

    Non trivial generalizations of the Schwinger pair production result

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    We present new, non trivial generalizations of the recent Tomaras, Tsamis and Woodard extension of the original Schwinger formula for charged pair production in a constant field.Comment: 11 page

    Non-perturbative QCD amplitudes in quenched and eikonal approximations

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    Even though approximated, strong coupling non-perturbative QCD amplitudes remain very difficult to obtain. In this article, in eikonal and quenched approximations, physical insights are presented that rely on the newly-discovered property of Effective Locality.Comment: Revised version (28 pages and 1 figure in REVTeX). Follow-up work of Eur. Phys. J. C65, pp. 395-411 (2010), (arXiv:1204.2038 [hep-ph]), and Ann. Phys. 327, pp. 2666-2690 (2012), (arXiv:1203.6137 [hep-ph]

    The Collision of Church and State: A Primer to Beth Din Arbitrarion and the New York Secular Courts

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    This Comment analyzes the interaction between secular courts and beth din proceedings (arbitration panels made up of specialists in halacha, or Jewish law). Part I examines the reasons why an independent Jewish religious court system is required and utilized despite the existence of a fair and equitable secular court system. It describes the Jewish legal principles involved, and how they impact both Jewish litigants and lawyers. Part II describes the mechanics of transforming a religious tribunal into a legally binding arbitration panel in New York State. Part III discusses the limited grounds upon which a beth din award may be vacated through statutory requirements and recent developments in the case law. It demonstrates the courts\u27 reluctance to treat beth din as a standard arbitration panel because of the possibility of encroaching on the Free Exercise Clause of the Constitution. Lastly, it identifies areas in which the courts have failed to vacate awards, seemingly deserving of vacature, due to a fundamental lack of understanding of Jewish mores and customs, demonstrating the need for further reform in this area of the law

    The configurational and standard force balances are not always statements of a single law

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    By studying the asympototic connection between phase-field and sharp-interface theories for transitions between two phases distinguished only by their constant free-energy densities, we show that the configurational force balance of the sharpinterface theory is completely unrelated to standard force balance. This demonstrates the fallacy of a recently asserted view that the balances for configurational and standard forces are never independent.published or submitted for publicationis not peer reviewe
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