标题： 带有高斯-博内修正的膨胀：超越慢滚 显示英文标题

标题： Inflation with Gauss-Bonnet correction: beyond slow-roll

摘要： 如果引入暴胀子与高斯-博内特项之间的耦合，许多因最新普朗克数据而被排除的暴胀模型可以再次变得可行。 标量谱指数和张量-标量比的预测通常使用慢滚近似进行计算。 在本文中，我们研究完整的运动方程并确定合理暴胀时期的必要初始条件。 我们推导了弗里德曼方程对于哈勃参数存在正解的条件。 然后我们研究了暴胀子可能被高斯-博内特项引起的局部势能极小值所困的可能性。 最后，我们在单项势能模型上展示了结果，包括二次势能和四次势能，并表明在四次情况下，慢滚近似变得不精确。 显示英文摘要

摘要： If a coupling between the inflaton and the Gauss-Bonnet term is introduced, many models of inflation that were ruled out by the most recent Planck data can be made viable again. The predictions for the scalar spectral index and tensor-to-scalar ratio are typically computed using the slow-roll approximation. In this paper we instead study the full equations of motion and determine the necessary initial conditions for reasonable inflation epoch. We derive the conditions under which the Friedmann equation admits positive solutions for the Hubble parameter. Then we study the possibility of the inflaton becoming trapped in a local potential minimum induced by the Gauss-Bonnet term. Finally we demonstrate the results on monomial potential models with a quadratic and a quartic potential and show that the slow-roll approximation becomes imprecise in the quartic case.