In this study, we have constructed a viable cosmological model characterized by the presence of the Gauss–Bonnet four-dimensional invariant, higher-order corrections to the low energy effective action motivated from heterotic superstring theory and a general exponential potential comparable to those obtained in higher dimensional supergravities. The field equations were studied by assuming a particular relation between the Hubble parameter and the time derivative of the scalar field. It was observed that, for specific relations between the free parameters in the theory, the universe is cyclic, expands and contracts alternately without singularity with an equation of state oscillating around −1. The model is found to fit the recent astrophysical data.

中文翻译：

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来自 Gauss-Bonnet 和超弦修正的循环非奇异宇宙

在这项研究中，我们构建了一个可行的宇宙学模型，其特征在于高斯-邦内四维不变性的存在，对由异质超弦理论激发的低能量有效作用的高阶修正，以及与在更高维的超引力。通过假设哈勃参数和标量场的时间导数之间的特定关系来研究场方程。观察到，对于理论中自由参数之间的特定关系，宇宙是循环的，膨胀和收缩交替，没有奇点，状态方程在-1附近振荡。发现该模型适合最近的天体物理数据。