97 research outputs found

    A scale-dependent cosmology for the inhomogeneous Universe

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    A scale-dependent cosmology is proposed in which the Robertson-Walker metric and the Einstein equation are modified in such a way that Ω0\Omega_0, H0H_0 and the age of the Universe all become scale-dependent. Its implications on the observational cosmology are discussed.Comment: 7 pages, in RevTex. To be appeared in TAUP '9

    Do the Age of the Universe and the Hubble Constant Depend on What Scale One Observes Them?

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    The apparent cosmological conflict between the age of the Universe, predicted in the standard Friedman cosmology by using the recent measurement of the larger Hubble constant from a direct calibration of the distance to the Virgo galaxy cluster, and the ages of the oldest stars and globular clusters is resolved by invoking the scale dependence of cosmological quantities, including the age of the Universe. The distance dependence or the running of cosmological quantities is motivated by the asymptotically-free higher- derivative quantum gravity. The running can also be derived by ``properly" modifying the Friedman equations. This property can also provide partial explanation of the apparent disagreement between the two recent measurements of the Hubble constant using NGC 4571 at 15 Mpc and NGC 5253 at 4 Mpc.Comment: Revtex file, 9 pages (no figures

    The localisation of ED1 antibody in the resorbing hard tissues of the periodontium

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    A dental hard tissue resorptive model was used to determine the periodontal ligament (PDL) distribution of lysosomal membrane antibody ED1 to cells of the macrophage-phagocyte lineage. Immunolabel was identified in mononuclear cells around inflammatory sites in the PDL, while multinu-clear cells were labelled in resorption bays present in both bone and dentine. As repair of the tissues occurred, the label became less obvious. The presence of strong ED1 label in alveolar bone marrow provided evidence supporting the haemopoietic origin of the similarly labelled PDL cells. Also, evidence confirming the current theory that multinucleated resorptive cells differentiate along a monocyte-macrophage pathway was provided. It was concluded that ED1 is a positive PDL marker for mononuclear and multinuclear cells involved in the inflammatory and resorptive processes
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