论文标题
有效的非最小二次重力和经典截止
Effective Non-Minimal Quadratic Gravity and the Classical Cut-Off
论文作者
论文摘要
在本文中，我们将二次引力视为某些未知的紫外线完全重力理论的低能量有效场理论。使用在二次重力中发生的Spin-2幽灵病理学，我们在各种构型中得出了低能量有效场理论的经典截止值的最大值。然后，我们添加更高秩序，自下而上，有效的术语。在每个顺序上，我们允许引入非最少耦合的标量字段项，并计算假定的$ \ Mathbb {z} _2 $对称性破坏标量字段的真空期望值。这种对称性破裂使我们引入了动作中的常数，以确保物理自旋2的自由度在平面近似中是无质量的，这是我们在整个工作中做出的隐含假设。然后，我们考虑我们不细化引入常数的情况，这导致了（反）de安静解决方案，然后我们可以扩展。所选宇宙常数的迹象是确定几何形状是保姆还是反DE保姆的主要因素。然后，扩展这种几何形状使我们能够将理论经典的截止值与扁平空间案例相比，与自由宇宙恒定参数成正比的量。
In this paper we consider Quadratic Gravity as a low energy effective field theory of some unknown UV-complete theory of gravity. Using the spin-2 ghost pathology that occurs in Quadratic Gravity, we derive maximum value for the classical cut-off of the low energy effective field theory in various configurations. We then add on higher order, bottom-up, effective terms. At each order we allow the introduction of non-minimally coupled scalar field terms, and we calculate the vacuum expectation value of the theory under an assumed $\mathbb{Z}_2$ symmetry breaking of the scalar field. This symmetry breaking leads us to introduce a constant in the action which is required to ensure that the physical spin-2 degree of freedom is massless in the flat space approximation, an implicit assumption we make throughout the work. We then consider the case in which we do not fine tune the introduced constant, which leads to an (Anti-)de Sitter solution about which we can then expand. The sign of the chosen cosmological constant is the major factor in determining whether the geometry is de Sitter or Anti-de Sitter. Then expanding about this geometry allows us to increase the theoretical classical cut-off as compared to the flat space case by an amount that is proportional to the free cosmological constant parameter.
