190 research outputs found

    Traversable Wormholes and Black Hole Complementarity

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    Black hole complementarity is incompatible with the existence of traversable wormholes. In fact, traversable wormholes cause problems for any theory where information comes out in the Hawking radiation.Comment: 4 pages, CALT-68-193

    THE INSTITUTIONAL COMPLEXITY OF BUSINESS SOCIAL RESPONSIBILITY (NATURE, INSTITUTIONS, MECHANISM)

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    Purpose: Business social responsibility or BSR is strengthened by innovative management and marketing practices of Russian enterprises to form their reputation capital and increase commercial benefits. The reasons of these ones are not able to explain in terms of full rationality. The aim of the paper is to examine nature and specifi city of BSR in institutional logics of the fi rm evolution. Methodology & Approach: The theoretical analyses presented in this paper are based on the tools of modern institutional theory and corporate management. BSR is considered as an institutional form of the compelled adaptation of corporations to growing requirements of civil society and regulators (protective reaction), as marketing technology of strengthening of a brand image (response) and as a way of expansion of norms and practices on counteragents and partners in global supply chains (return reaction). Implications for future research: The paper highlights the puzzling essence of BSR determined political, cultural and other social institutions which have produced exogenous effects on organizational behavior. Better understanding of an economic mechanism of introducing BSR institute into a representative firm accelerates the adaptive process of this transplanted institute. Findings: The system of institutions of the socio-responsible company is detailed. Positive effects, contradictions and the mechanism of social orientation of corporate sector are proved.

    The general Leigh-Strassler deformation and integrability

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    The success of the identification of the planar dilatation operator of N=4 SYM with an integrable spin chain Hamiltonian has raised the question if this also is valid for a deformed theory. Several deformations of SYM have recently been under investigation in this context. In this work we consider the general Leigh-Strassler deformation. For the generic case the S-matrix techniques cannot be used to prove integrability. Instead we use R-matrix techniques to study integrability. Some new integrable points in the parameter space are found.Comment: 22 pages, 8 figures, reference adde

    Star product and the general Leigh-Strassler deformation

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    We extend the definition of the star product introduced by Lunin and Maldacena to study marginal deformations of N=4 SYM. The essential difference from the latter is that instead of considering U(1)xU(1) non-R-symmetry, with charges in a corresponding diagonal matrix, we consider two Z_3-symmetries followed by an SU(3) transformation, with resulting off-diagonal elements. From this procedure we obtain a more general Leigh-Strassler deformation, including cubic terms with the same index, for specific values of the coupling constants. We argue that the conformal property of N=4 SYM is preserved, in both beta- (one-parameter) and gamma_{i}-deformed (three-parameters) theories, since the deformation for each amplitude can be extracted in a prefactor. We also conclude that the obtained amplitudes should follow the iterative structure of MHV amplitudes found by Bern, Dixon and Smirnov.Comment: 21 pages, no figures, JHEP3, v2: references added, v3: appendix A added, v4: clarification in section 3.

    Greybody factor for a scalar field coupling to Einstein's tensor

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    We study the greybody factor and Hawking radiation for a scalar field coupling to Einstein's tensor in the background of Reissner-Nordstr\"om black hole in the low-energy approximation. We find that the presence of the coupling terms modifies the standard results in the greybody factor and Hawking radiation. Our results show that both the absorption probability and Hawking radiation increase with the coupling constant. Moreover, we also find that for the stronger coupling, the charge of black hole enhances the absorption probability and Hawking radiation of the scalar field, which is different from those of ones without coupling to Einstein's tensor in the black hole spacetime.Comment: 14 pages, 6 figures, Accepted by PL

    Entropy, holography and the second law

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    The geometric entropy in quantum field theory is not a Lorentz scalar and has no invariant meaning, while the black hole entropy is invariant. Renormalization of entropy and energy for reduced density matrices may lead to the negative free energy even if no boundary conditions are imposed. Presence of particles outside the horizon of a uniformly accelerated observer prevents the description in terms of a single Unruh temperature.Comment: 4 pages, RevTex 4, 1 eps figur

    Axial symmetries in lattice QCD with Kaplan fermions

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    This paper develops in detail a lattice definition of QCD based on the chiral defect fermions recently introduced by Kaplan. The revised version provides missing technical details in the proof that non-singlet axial symmetries become exact in the limit of an infinite fifth dimension. Also several minor errors are corrected.Comment: LaTeX, 29 p

    The staggered domain wall fermion method

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    A different lattice fermion method is introduced. Staggered domain wall fermions are defined in 2n+1 dimensions and describe 2^n flavors of light lattice fermions with exact U(1) x U(1) chiral symmetry in 2n dimensions. As the size of the extra dimension becomes large, 2^n chiral flavors with the same chiral charge are expected to be localized on each boundary and the full SU(2^n) x SU(2^n) flavor chiral symmetry is expected to be recovered. SDWF give a different perspective into the inherent flavor mixing of lattice fermions and by design present an advantage for numerical simulations of lattice QCD thermodynamics. The chiral and topological index properties of the SDWF Dirac operator are investigated. And, there is a surprise ending...Comment: revtex4, 7 figures, minor revisions, 2 references adde

    Semiclassical Stability of the Extreme Reissner-Nordstrom Black Hole

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    The stress-energy tensor of a free quantized scalar field is calculated in the extreme Reissner-Nordstr\"{o}m black hole spacetime in the zero temperature vacuum state. The stress-energy appears to be regular on the event horizon, contrary to the suggestion provided by two-dimensional calculations. An analytic calculation on the event horizon for a thermal state shows that if the temperature is nonzero then the stress-energy diverges strongly there.Comment: 10 pages, REVTeX, 4 figures in separate uuencoded compressed fil

    Comments on the beta-deformed N=4 SYM Theory

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    Several calculations of 2- and 3-point correlation functions in the deformed theory are presented. The central charge in the Lunin-Maldacena gravity dual is shown to be independent of the deformation parameter. Calculations show that 2- and 3-point functions of chiral primary operators have no radiative corrections to lowest order in the interactions. Correlators of the operator tr(Z_1Z_2), which has not previously been identified as chiral primary, also have vanishing lowest order corrections.Comment: 18 pages, 1 figure. 2nd version: typos corrected, one reference adde
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