Quantum gravity corrections to sequestering

隔离理论是对引力的一种修正，它为宇宙常数问题提供了部分解决方案，因为它阻止了标准模型对真空能量的贡献来自引力。经典隔离在局部上与经典广义相对论在壳层上是等价的，尽管在全局上这两个理论是不同的。然而，量子引力（QG）修正有望打破两者之间的（局部）等效。通过采用Donoghue的有效场论（EFT）方法来研究某些截止点（通常被认为是普朗克尺度）以下的QG，我们将研究来自引力子环在隔离中的领先阶修正。当然，为了测试该提议对引力子环的鲁棒性，我们的主要兴趣在于对主导低能动力学的相关算子的修正。例如，考虑引力子对宇宙常数的修正：在一个环中，我们不期望有任何这样的修正，所以我们需要去两个环才能得到一个非平凡的结果。然后我们要问引力子的真空环是否和物质环一样有效地隔离。首先，我们将在经典封存模型的背景下问这个问题。我们天真地认为，引力子的真空能不会像它们的标准模型那样容易相互抵消。量化这种影响的大小是很重要的，如果这是一个问题，那么就需要从我们模型的QG改进版本中获得一些见解。我们还需要考虑其他阶低能量QG修正，因为它们可能潜在地改变低能EFT的期望结构。即使在物质领域，这也可能破坏抵消机制，尽管这种效应肯定会被普朗克抑制，但我们必须适当地量化它。此外，QG修正也有望改变对GR的局部等价。这是因为等价只在壳层上成立，而在壳层外不成立，所以可以想象环路产生不同的牛顿定律的QG修正。

The sequestering proposal is a modification of gravity that provides a partial solution to the cosmological constant problem, inasmuch as it prevents the standard model contributions to vacuum energy from gravitating. Classical sequestering is locally equivalent to classical General Relativity on shell, although globally the theories differ. Nevertheless, Quantum gravity (QG) corrections are expected to break the (local) equivalence between the two. By adopting Donoghue's effective field theory (EFT) approach to QG below some cut-off (usually taken to be the Planck scale) we will study the leading order corrections coming from graviton loops in sequestering. Of course, to test the robustness of the proposal against graviton loops, our main interest lies in the corrections to the relevant operators that dominate the low energy dynamics. Consider, for example, the graviton corrections to the cosmological constant: at one loop we do not expect there to be any such corrections, so we will need to go to two loops for a non-trivial result. We then ask whether or not vacuum loops of gravitons sequester as efficiently as the matter loops. Initially we will ask this in the context of the classical model of sequestering. Naively we do not expect the graviton vacuum energy to cancel as readily as their standard model counterparts. It is important to quantify the size of this effect, and if it is a problem, to get some insight into what is required from a QG improved version of our model. We also need to consider the other leading order low energy QG corrections as these could potentially alter the desired structure of the low energy EFT. This could spoil the cancellation mechanism even in the matter sector, and although such an effect will surely be Planck suppressed, it is imperative we quantify this properly. Furthermore, QG corrections are also expected to alter the local equivalence to GR. This is because the equivalence is only true on shell, and not off shell, so one could imagine loops yielding distinct QG corrections to Newton's law.