We derive the power spectrum of primordial quantum fluctuations in an inflationary universe for curvature parameter \({\mathcal {K}}=1\). This is achieved through a Born–Oppenheimer type of approximation scheme from the Wheeler–DeWitt equation of canonical quantum gravity using gauge-invariant variables. Compared to the flat model, the closed model exhibits a deficit of power at large scales.

中文翻译：

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封闭宇宙暴胀模型中扰动的功率谱

我们为曲率参数\({\mathcal {K}}=1\)推导出暴胀宇宙中原始量子涨落的功率谱。这是通过使用规范不变变量的规范量子引力的 Wheeler-DeWitt 方程的 Born-Oppenheimer 类型的近似方案来实现的。与平面模型相比，封闭模型在大尺度上表现出功率不足。