A model of the universe in which the early universe undergoes a period of exponentially rapid expansion, required to develop the high degree of homogeneity shown by the present-day universe.宇宙膨胀：一种宇宙模式，早期的宇宙所经历的一段以指数速度增加快速膨胀的期间，为发展成今日所见高度同构型的宇宙所必须经历的时期