The asymptotic safety scenario in quantum gravity is reviewed, according to which a renormalizable quantum theory of the gravitational field is feasible which reconciles asymptotically safe couplings with unitarity. The evidence from symmetry truncations and from the truncated flow of the effective average action is presented in detail. A dimensional reduction phenomenon for the residual interactions in the extreme ultraviolet links both results. For practical reasons the background effective action is used as the central object in the quantum theory. In terms of it criteria for a continuum limit are formulated and the notion of a background geometry self-consistently determined by the quantum dynamics is presented. Self-contained appendices provide prerequisites on the background effective action, the effective average action, and their respective renormalization flows.

中文翻译：

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量子引力中的渐近安全情景。

回顾了量子引力中的渐近安全场景，根据该场景，可重整化的引力场量子理论是可行的，它将渐近安全耦合与单一性相协调。详细介绍了对称截断和有效平均作用截断流的证据。极紫外中残余相互作用的降维现象将这两个结果联系起来。由于实际原因，背景有效作用被用作量子理论中的中心对象。就它而言，制定了连续极限的标准，并提出了由量子动力学自洽确定的背景几何概念。独立的附录提供了背景有效动作、有效平均动作的先决条件，