Research PapersNo Access

DISCRETE GRAVITY AND ITS CONTINUUM LIMIT

YI LING

CCAST (World Laboratory), P. O. Box 8730, Beijing 100080, China

Institute of Theoretical Physics, Chinese Academy of Sciences, P. O. Box 2735, Beijing 100080, China

https://doi.org/10.1142/S0217732305015793Cited by:0 (Source: Crossref)

Abstract

Recently Gambini and Pullin proposed a new consistent discrete approach to quantum gravity and applied it to cosmological models. One remarkable result of this approach is that the cosmological singularity can be avoided in a general fashion. However, whether the continuum limit of such discretized theories exists is model dependent. In the case of massless scalar field coupled to gravity with Λ=0, the continuum limit can only be achieved by fine tuning the recurrence constant. We regard this failure as the implication that cosmological constant should vary with time. For this reason we replace the massless scalar field by Chaplygin gas which may contribute an effective cosmological constant term with the evolution of the universe. It turns out that the continuum limit can indeed be reached in this case.

Keywords:

PACS: 04.60.Nc, 04.20.Dw, 04.60.Kz

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