Scalar and tensor cosmological perturbations during an inflationary universe scenario in the context of the a generalized gravity theory are studied. This analyze is carried out considering an ansatz on the variables associated to scalar and tensor perturbation ( $$z_s$$ z s and $$z_t$$ z t ) in the Jordan frame. In this context, we analyze two different Ansatze for the ratio $$z_s/z_t$$ z s / z t , and we study in great detail the analytical and exact solutions for the cosmological perturbations together with the corresponding reconstruction of the background variables. Recent observational data from the Planck 2018 results are employed to constrain the parameters of each of the models.

中文翻译：

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从广义引力理论重建宇宙学扰动的精确解

在广义引力理论的背景下，研究了膨胀宇宙情景中的标量和张量宇宙学扰动。执行此分析时考虑了 Jordan 框架中与标量和张量扰动（ $$z_s$$ zs 和 $$z_t$$ zt ）相关的变量的 ansatz。在这种情况下，我们分析了两个不同的 Ansatze 的比率 $$z_s/z_t$$ zs / zt ，并且我们非常详细地研究了宇宙学扰动的解析解和精确解以及背景变量的相应重建。普朗克 2018 结果的最新观测数据用于约束每个模型的参数。