标题： 新的量子引力自旋泡沫模型 显示英文标题

标题： New Spin Foam Models of Quantum Gravity

摘要： 我们对巴雷特-克兰自旋泡沫量子引力模型进行了简要和批判性的回顾。然后我们描述了两个新的自旋泡沫模型，这些模型是通过直接量化广义相对论得到的，并且没有巴雷特-克兰模型的一些缺点。这些是环量子引力中嵌入自旋网络的自旋泡沫不变量模型，以及基于路径积分中四维矢量积分的自旋泡沫模型。 显示英文摘要

摘要： We give a brief and a critical review of the Barret-Crane spin foam models of quantum gravity. Then we describe two new spin foam models which are obtained by direct quantization of General Relativity and do not have some of the drawbacks of the Barret-Crane models. These are the model of spin foam invariants for the embedded spin networks in loop quantum gravity and the spin foam model based on the integration of the tetrads in the path integral for the Palatini action.