Gravitational Two-Loop Counterterm Is Asymptotically Safe.
Gravitational Two-Loop Counterterm Is Asymptotically Safe.
复制标题
DOI：
10.1103/physrevlett.116.211302
复制
发表时间：
2016-01
影响因子：
8.6
通讯作者：
H. Gies;B. Knorr;Stefan Lippoldt;F. Saueressig
中科院分区：
文献类型：
--
作者：
H. Gies;B. Knorr;Stefan Lippoldt;F. Saueressig
温伯格的渐近安全场景提供了一种优雅的机制，可以在量子场论框架内基于重正化群流的非高斯不动点构建量子引力论。在这项工作中，我们报告了证明这种情况有效性的新证据，使用函数重整化群技术来确定爱因斯坦-希尔伯特作用的重整化群流，并辅以 Goroff 和 Sagnotti 发现的双循环反项。由此产生的 beta 函数系统包含三个与尺度相关的耦合常数，并表现出一个非高斯不动点，该不动点构成了在爱因斯坦-希尔伯特作用水平上发现的不动点的自然延伸。该固定点表现出两个紫外线吸引方向和一个排斥方向，支持低维紫外线临界超曲面。我们的结果消除了长期以来的批评，即一旦投影空间中包含“适当的微扰反项”，渐近安全性将无法生存。
Weinberg's asymptotic safety scenario provides an elegant mechanism to construct a quantum theory of gravity within the framework of quantum field theory based on a non-Gaussian fixed point of the renormalization group flow. In this work we report novel evidence for the validity of this scenario, using functional renormalization group techniques to determine the renormalization group flow of the Einstein-Hilbert action supplemented by the two-loop counterterm found by Goroff and Sagnotti. The resulting system of beta functions comprises three scale-dependent coupling constants and exhibits a non-Gaussian fixed point which constitutes the natural extension of the one found at the level of the Einstein-Hilbert action. The fixed point exhibits two ultraviolet attractive and one repulsive direction supporting a low-dimensional UV-critical hypersurface. Our result vanquishes the long-standing criticism that asymptotic safety will not survive once a "proper perturbative counterterm" is included in the projection space.