论文标题
TGFT量子重力中的平均场相变
Mean-field phase transitions in TGFT quantum gravity
论文作者
论文摘要
控制连续性极限并提取有效的重力物理是基于量子离散结构的量子重力方法的共同挑战。量子重力在紧张群体场理论（TGFT）方面的描述最近导致了其在现象学，尤其是宇宙学上的应用方面的很大进步。该应用依赖于通过平均场理论描述的非平凡真空（冷凝水）状态的相位过渡的假设，这一假设由于相关TGFT模型的复杂性而被完全重新归一化的组流量分析很难证实。在这里，我们证明，由于逼真的量子几何TGFT模型的特定成分：联合非本地相互作用，自由度和Lorentz组数据以及微生物的编码。这大大加强了在集体场和自旋泡沫量子重力中存在有意义的连续性引力状态的证据，这种现象学是在平均场近似中明确计算的现象学。
Controlling the continuum limit and extracting effective gravitational physics are shared challenges for quantum gravity approaches based on quantum discrete structures. The description of quantum gravity in terms of tensorial group field theory (TGFT) has recently led to much progress in its application to phenomenology, in particular cosmology. This application relies on the assumption of a phase transition to a nontrivial vacuum (condensate) state describable by mean-field theory, an assumption that is difficult to corroborate by a full renormalization group flow analysis due to the complexity of the relevant TGFT models. Here we demonstrate that this assumption is justified due to the specific ingredients of realistic quantum geometric TGFT models: combinatorially non-local interactions, matter degrees of freedom and Lorentz group data together with the encoding of micro-causality. This greatly strengthens the evidence for the existence of a meaningful continuum gravitational regime in group-field and spin-foam quantum gravity, the phenomenology of which is amenable to explicit computations in a mean-field approximation.
