论文标题
$ O（N）$ - 对称标量场和Sitter的量子反应在重新归一化点处：重新归一化方案和宇宙学常数的筛选
Quantum backreaction of $O(N)$-symmetric scalar fields and de Sitter spacetimes at the renormalization point: renormalization schemes and the screening of the cosmological constant
论文作者
论文摘要
我们考虑了$ n $自我相互作用的量子标量字段的理论，具有四分之一的$ o（n）$ - 对称势，并在通用弯曲的时空中具有耦合常数$λ$。我们分析了半经典爱因斯坦方程在领先顺序上以$ 1/n $的扩展为不同的肾上管方案的扩展，即：传统的范围是将时空的几何形状设定为在重新归一化点上是minkowski的几何形状，并在[1,2]中固定了一部分，该方案是在[1,2]中固定的。尤其是，我们研究了位于保姆的田野的量子反应，其质量比膨胀率$ h $小得多。我们发现，使用经典的DE Sitter背景解决方案在重新归一化点上使用的方案是研究对Sitter SpaceTime的量子效应的最合适的方案。采用这种方案，我们获得的反应被$ h^2/m_ {pl}^2 $抑制，而没有$ \lnλ$的对数增强因子，由于这种量子场的反射，因此仅对经典宇宙学常数进行了少量筛选。我们指出，新方案的使用也比传统方案更合适，以研究与宇宙学相关的其他空间中的量子效应。
We consider a theory of $N$ self-interacting quantum scalar fields with quartic $O(N)$-symmetric potential, with a coupling constant $λ$, in a generic curved spacetime. We analyze the renormalization process of the Semiclassical Einstein Equations at leading order in the $1/N$ expansion for different renormailzation schemes, namely: the traditional one that sets the geometry of the spacetime to be Minkowski at the renormalization point, and new schemes (originally proposed in [1,2]) which set the geometry to be that of a fixed de Sitter spacetime. In particular, we study the quantum backreaction for fields in de Sitter spacetimes with masses much smaller than the expansion rate $H$. We find that the scheme that uses the classical de Sitter background solution at the renormalization point, stands out as the most appropriate to study the quantum effects on de Sitter spacetimes. Adopting such scheme we obtain the backreaction is suppressed by $H^2/M_{pl}^2$ with no logarithmic enhancement factor of $\lnλ$, giving only a small screening of the classical cosmological constant due to the backreaction of such quantum fields. We point out the use of the new schemes can also be more appropriate than the traditional one to study quantum effects in other spacetimes relevant for cosmology.
