期刊
CLASSICAL AND QUANTUM GRAVITY
卷 28, 期 22, 页码 -出版社
IOP PUBLISHING LTD
DOI: 10.1088/0264-9381/28/22/225004
关键词
-
类别
资金
- FCT [PTDC/MAT/099880/2008]
- [SFRH/BPD/46376/2008]
- Fundação para a Ciência e a Tecnologia [SFRH/BPD/46376/2008] Funding Source: FCT
We define an effective action for spin-foam models of quantum gravity by adapting the background field method from quantum field theory. We show that the Regge action is the leading term in the semi-classical expansion of the spin-foam effective action if the vertex amplitude has the large-spin asymptotics which is proportional to an exponential function of the vertex Regge action. In the case of the known three-dimensional and four-dimensional spin-foam models, this amounts to modifying the vertex amplitude such that the exponential asymptotics is obtained. In particular, we show that the ELPR/FK model vertex amplitude can be modified such that the new model is finite and has the Einstein-Hilbert action as its classical limit. We also calculate the first-order and some of the second-order quantum corrections in the semi-classical expansion of the effective action.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据