伪子与量子引力的经典化：FLRW度规
Fakeons and the classicization of quantum gravity: the FLRW metric
摘要：
在某些假设下，通过将不需要的自由度量化为伪量（fakeon），可以理解高阶导数理论，这些伪量后来被投影掉。然后通过对量子理论的经典化，得到了真正的经典极限。由于量子场论是用微扰的形式表述的，经典化也是微扰的。在一般情况下推导出一些性质后，我们考虑了从fakeon思想中出现的量子引力理论，并研究了它的经典化，重点是FLRW度规。我们指出的情况下，假子投影可以准确地处理，其中包括辐射，真空能量密度和两者的组合，以及情况下，它不能，其中包括灰尘。一般来说，经典极限与它所来自的量子理论有许多共同的特征，包括不可能写出完整的、“精确的”场方程，以至于渐近级数和非微扰效应开始起作用。
英文摘要：
Under certain assumptions, it is possible to make sense of higher derivative theories by quantizing the unwanted degrees of freedom as fakeons, which are later projected away. Then the true classical limit is obtained by classicizing the quantum theory. Since quantum field theory is formulated perturbatively, the classicization is also perturbative. After deriving a number of properties in a general setting, we consider the theory of quantum gravity that emerges from the fakeon idea and study its classicization, focusing on the FLRW metric. We point out cases where the fakeon projection can be handled exactly, which include radiation, the vacuum energy density and the combination of the two, and cases where it cannot, which include dust. Generically, the classical limit shares many features with the quantum theory it comes from, including the impossibility to write down complete, "exact" field equations, to the extent that asymptotic series and nonperturbative effects come into play.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
