In this work, we calculate the tensor power spectrum and the tensor-to-scalar ratio r within the frame of the Starobinsky inflationary model using the improved uniform approximation method and the third-order phase-integral method. We compare our results with those obtained with numerical integration and the slow-roll approximation to second-order. We have obtained consistent values of r using the different approximations, and r is inside the interval reported by observations.

中文翻译：

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Starobinsky暴胀模型中张量功率谱的半经典分析

在这项工作中，我们计算了张量功率谱和张量与标量比r在 Starobinsky 暴胀模型的框架内使用改进的均匀近似法和三阶相位积分法。我们将我们的结果与通过数值积分和慢滚近似二阶获得的结果进行比较。我们获得了一致的价值观r使用不同的近似值，并且r在观察报告的区间内。