To investigate the cosmic future of the universe, first, we obtain the particle and event horizons, and their evolution in time for three well-known varying cosmological constant models. We investigate the implications of these varying cosmological constant models on the particle and event horizons, and their time evolution during the universe history and future. We study the behaviours around the origin and at the far future of the universe for all cases. Finally, we obtained the general behaviours of the horizons and time evolution functions with respect to the general scale factor a for each of the three cases of varying cosmological constant. The results show that for two of our three cases, a big bounce scenario is inevitable for the universe starting from the big bang and ending up with a bouncing re-collapse to its initial state.

为了研究宇宙的宇宙未来，首先，我们获得了三个众所周知的不同宇宙常数模型的粒子和事件视界，以及它们在时间上的演化。我们研究了这些不同的宇宙常数模型对粒子和事件视界的影响，以及它们在宇宙历史和未来的时间演化。我们研究所有情况下宇宙起源和遥远未来的行为。最后，我们得到了视界和时间演化函数相对于一般尺度因子a的一般行为对于不同宇宙学常数的三种情况中的每一种。结果表明，对于我们的三个案例中的两个，从大爆炸开始到最终反弹并重新坍缩到其初始状态的宇宙都不可避免地会出现大反弹。