论文标题
$α$ -VACUUM中的graviton非高斯性
Graviton non-gaussianity in $α$-vacuum
论文作者
论文摘要
我们计算了一般相对论中de Sitter空间上一般$α$ -VACUUM中张量的张扰动的领先顺序的非高斯性，即双光线。除了众所周知的束 - 戴维（BD）真空外，还退出了由真实参数$α$和$ n $ ϕ $代表的无限的De Sitter不变真空吸尘器，其中$α= 0 $是BD真空吸尘器。它们被称为$α$ -VACUA。在标准的慢速通货膨胀中，由于保姆不变不再适用，因此$α$ -VACUA在严格的意义上失去了相关性。但是，如果我们假设参数$α$仅弱取决于具有适当紫外线截止的波数，则可以考虑伪$α$ -VACUA。在背景时空是纯净保姆的错误真空通胀的情况下，确实可以实现非平凡（非BD）$α$ -VACUUM。我们发现一个有趣的结果是，即使频谱太小而无法检测到，双光谱也可能会呈指数增强以指数增强以检测到。
We compute the leading order non-Gaussianity, i.e., the bispectrum, of the tensor perturbation in the general $α$-vacuum on de Sitter space in general relativity. In addition to the well-known Bunch-Davies (BD) vacuum, there exits an infinite number of de Sitter invariant vacua represented by a real parameter $α$ and a phase $ϕ$, with $α=0$ being the BD vacuum. They are called $α$-vacua. In the standard slow-roll inflation, as de Sitter invariance no longer applies, the $α$-vacua lose its relevance in the rigorous sense. Nevertheless, if we assume that the parameter $α$ is only weakly dependent on the wavenumber with an appropriate UV cutoff, we may consider pseudo-$α$-vacua. In the case of false vacuum inflation where the background spacetime is pure de Sitter, a non-trivial (non-BD) $α$-vacuum could indeed be realized. We find an intriguing result that the bispectrum may be exponentially enhanced to be detectable by observation even if the spectrum is too small to be detected.
