Recent data suggest that the Universe could be positively curved. Combined with an inflationary stage, this might lead to a curvature bounce instead of the Big Bang. The background evolution is presented, as a function of the parameters controlling the cosmic evolution. The primordial tensor spectrum is also calculated and possible observational footprints of the model are underlined. Several potentials are considered and general remarks are made about "naturalness" in this context.

中文翻译：

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广义相对论中的曲率反弹：背景和原始光谱

最近的数据表明，宇宙可能是正弯曲的。结合暴胀阶段，这可能会导致曲率反弹而不是大爆炸。背景演化被呈现为控制宇宙演化的参数的函数。还计算了原始张量谱，并用下划线标出了模型可能的观测足迹。在这种情况下，考虑了几种潜力，并对“自然性”进行了一般性评论。