1,077 research outputs found

    Place of manufacture diversification in cyclical development of the enterprise

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    The relevance of the researched problem is caused by the fact that diversification is one of the best options for reforming enterprises. The aim of the research: to consider changes in production of outputs in development cycles of the enterprise. This will help to reveal the nature of manufacture diversification. The leading method to the research of this problem is the system approach, which allows to elicit factors promoting formation of business mechanism of manufacture diversification under the conditions of volatile economic environment. The results of the research are: it is offered to enhance the existing classification of enterprises by nomenclative and technological characteristic, taking into account the specific nature of processing capacity. The materials of the research can be useful for control bodies of enterprises when taking constructive steps in the sphere of manufacture diversification and strategy development. © 2016 Erofeev and Smolin

    OPERA neutrinos and relativity

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    In a recent study, Cohen and Glashow argue that superluminal neutrinos of the type recently reported by OPERA should be affected by anomalous Cherenkov-like processes. This causes them to loose much of their energy before reaching the OPERA detectors. Related concerns were reported also by Gonzalez-Mestres and Bi et. al., who argued that pions cannot decay to superluminal neutrinos over part of the energy range studied by OPERA. We observe here that these arguments are set within a framework in which Lorentz symmetry is broken, by the presence of a preferred frame. We further show that these anomalous processes are forbidden if Lorentz symmetry is instead "deformed", preserving the relativity of inertial frames. These deformations add non-linear terms to energy momentum relations, conservation laws and Lorentz transformations in a way that is consistent with the relativity of inertial observers.Comment: 5 pages, some citations added; in v3 a footnote added and minor changes in the text made, the final version to appear in MPL

    Relative Locality in κ\kappa-Poincar\'e

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    We show that the κ\kappa-Poincar\'e Hopf algebra can be interpreted in the framework of curved momentum space leading to the relativity of locality \cite{AFKS}. We study the geometric properties of the momentum space described by κ\kappa-Poincar\'e, and derive the consequences for particles propagation and energy-momentum conservation laws in interaction vertices, obtaining for the first time a coherent and fully workable model of the deformed relativistic kinematics implied by κ\kappa-Poincar\'e. We describe the action of boost transformations on multi-particles systems, showing that in order to keep covariant the composed momenta it is necessary to introduce a dependence of the rapidity parameter on the particles momenta themselves. Finally, we show that this particular form of the boost transformations keeps the validity of the relativity principle, demonstrating the invariance of the equations of motion under boost transformations.Comment: 24 pages, 4 figures, 1 table. v2 matches accepted CQG versio

    The linearization of the Kodama state

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    We study the question of whether the linearization of the Kodama state around classical deSitter spacetime is normalizable in the inner product of the theory of linearized gravitons on deSitter spacetime. We find the answer is no in the Lorentzian theory. However, in the Euclidean theory the corresponding linearized Kodama state is delta-functional normalizable. We discuss whether this result invalidates the conjecture that the full Kodama state is a good physical state for quantum gravity with positive cosmological constant.Comment: 14 pages, statement on the corresponding Yang-Mills case correcte

    Relative locality: A deepening of the relativity principle

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    We describe a recently introduced principle of relative locality which we propose governs a regime of quantum gravitational phenomena accessible to experimental investigation. This regime comprises phenomena in which \hbar and GNG_N may be neglected, while their ratio, the Planck mass Mp=/GNM_p =\sqrt{\hbar / G_N}, is important. We propose that MpM_p governs the scale at which momentum space may have a curved geometry. We find that there are striking consequences for the concept of locality. The description of events in spacetime now depends on the energy used to probe it. But there remains an invariant description of physics in phase space. There is furthermore a reasonable expectation that the geometry of momentum space can be measured experimentally using astrophysical observations.Comment: 8 pages, Latex; this essay was awarded Second Prize in the 2011 Essay Competition of the Gravity Research Foundatio

    Rainbow universe

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    The formalism of rainbow gravity is studied in a cosmological setting. We consider the very early universe which is radiation dominated. A novel treatment in our paper is to look for an ``averaged'' cosmological metric probed by radiation particles themselves. Taking their cosmological evolution into account, we derive the modified Friedmann-Robertson-Walker(FRW) equations which is a generalization of the solution presented by Magueijo and Smolin. Based on this phenomenological cosmological model we argue that the spacetime curvature has an upper bound such that the cosmological singularity is absent. These modified FRWFRW equations can be treated as effective equations in the semi-classical framework of quantum gravity and its analogy with the one recently proposed in loop quantum cosmology is also discussed.Comment: 5 page

    Ideal-Modified Bosonic Gas Trapped in an Arbitrary Three Dimensional Power-Law Potential

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    We analyze the effects caused by an anomalous single-particle dispersion relation suggested in several quantum-gravity models, upon the thermodynamics of a Bose-Einstein condensate trapped in a generic 3-dimensional power-law potential. We prove that the shift in the condensation temperature, caused by a deformed dispersion relation, described as a non-trivial function of the number of particles and the shape associated to the corresponding trap, could provide bounds for the parameters associated to such deformation. Additionally, we calculate the fluctuations in the number of particles as a criterium of thermodynamic stability for these systems. We show that the apparent instability caused by the anomalous fluctuations in the thermodynamic limit can be suppressed considering the lowest energy associated to the system in question.Comment: 10 pages. arXiv admin note: text overlap with arXiv:1202.380

    Constraints on the quantum gravity scale from kappa - Minkowski spacetime

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    We compare two versions of deformed dispersion relations (energy vs momenta and momenta vs energy) and the corresponding time delay up to the second order accuracy in the quantum gravity scale (deformation parameter). A general framework describing modified dispersion relations and time delay with respect to different noncommutative kappa -Minkowski spacetime realizations is firstly proposed here and it covers all the cases introduced in the literature. It is shown that some of the realizations provide certain bounds on quadratic corrections, i.e. on quantum gravity scale, but it is not excluded in our framework that quantum gravity scale is the Planck scale. We also show how the coefficients in the dispersion relations can be obtained through a multiparameter fit of the gamma ray burst (GRB) data.Comment: 9 pages, final published version, revised abstract, introduction and conclusion, to make it clear to general reade
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