We explore the inflationary dynamics and reheating predictions of the fourth-order generalized polynomial inflation model featuring adjustable saddle-point position and flatness near the saddle point for both small and large field cases, based on the latest Planck 2018 Cosmic Microwave Background (CMB) and BICEP/Keck data. We observe that the small field case, with saddle points proximate to the origin, exhibits a significantly lower tensor-to-scalar ratio compared to the large field case. Additionally, the spectral index of the curvature perturbation increases as the flatness near the potential saddle point decreases. Through an analysis of the interplay between inflation and reheating parameters derived from the expansion history of the pivot CMB scale, we establish a permissible range for the reheating parameters. We find that both the small and large cases of polynomial inflation can be consistent with the latest observations due to potential flatness reduction, except for the case where the saddle point deviates significantly from the origin, and the reheating process accentuates the disparities in parameter space between small and large field inflationary scenarios.

中文翻译：

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小场和大场多项式暴胀中的暴胀和再加热预测


我们基于最新的普朗克 2018 年宇宙微波背景（CMB）和BICEP/Keck 数据。我们观察到，与大场情况相比，鞍点接近原点的小场情况表现出明显较低的张量与标量比。此外，曲率扰动的谱指数随着潜在鞍点附近的平坦度降低而增加。通过分析从枢轴 CMB 规模的扩张历史得出的充气和再加热参数之间的相互作用，我们建立了再加热参数的允许范围。我们发现，由于潜在的平坦度降低，多项式膨胀的小案例和大案例都可以与最新观察结果一致，除了鞍点显着偏离原点的情况，以及再加热过程加剧了参数空间之间的差异。小领域和大领域的通货膨胀情景。