96 research outputs found

    The shadows of quantum gravity on Bell's inequality

    Full text link
    The validity of quantum mechanical operators in the presence of quantum aspects of gravity is a subject of investigation since they may not hold true and require generalization. One of the key objectives of the present study is to examine the impact of such generalizations on the non-locality that is inherent in quantum mechanics and manifests itself in Bell's inequality. Another aspect of the study is to analyze the consequences of introducing a non-zero minimal length for the well-established Bell's inequality. The findings of this research are expected to contribute to the theoretical understanding of the interplay between quantum mechanics and gravity

    Quantum mechanics and geodesic deviation in the brane world

    Full text link
    We investigate the induced geodesic deviation equations in the brane world models, in which all the matter forces except gravity are confined on the 3-brane. Also, the Newtonian limit of induced geodesic deviation equation is studied. We show that in the first Randall-Sundrum model the Bohr-Sommerfeld quantization rule is as a result of consistency between the geodesic and geodesic deviation equations. This indicates that the path of test particle is made up of integral multiples of a fundamental Compton-type unit of length h/mch/mc.Comment: 5 pages, no figure

    Classical and quantum spinor cosmology with signature change

    Full text link
    We study the classical and quantum cosmology of a universe in which the matter source is a massive Dirac spinor field and consider cases where such fields are either free or self-interacting. We focus attention on the spatially flat Robertson-Walker cosmology and classify the solutions of the Einstein-Dirac system in the case of zero, negative and positive cosmological constant Λ\Lambda. For Λ<0\Lambda<0, these solutions exhibit signature transitions from a Euclidean to a Lorentzian domain. In the case of massless spinor fields it is found that signature changing solutions do not exist when the field is free while in the case of a self-interacting spinor field such solutions may exist. The resulting quantum cosmology and the corresponding Wheeler-DeWitt equation are also studied for both free and self interacting spinor fields and closed form expressions for the wavefunction of the universe are presented. These solutions suggest a quantization rule for the energy.Comment: 13 pages, 4 figure

    Stabilization of internal space in noncommutative multidimensional cosmology

    Get PDF
    We study the cosmological aspects of a noncommutative, multidimensional universe where the matter source is assumed to be a scalar field which does not commute with the internal scale factor. We show that such noncommutativity results in the internal dimensions being stabilizedComment: 8 pages, 1 figure, to appear in IJMP

    On the thermodynamics of reconciling quantum and gravity

    Full text link
    Is thermodynamics consistent with the quantum gravity reconciliation hypothesis [A. G. Cohen et al. Phys. Rev. Lett. 82, 4971 (1999)], which establishes holographic dark energy models? Here, we have attempted to address this issue in the affirmative by concentrating on the first law of thermodynamics
    • …
    corecore