论文标题
纯净的保姆空间，岛上的时间返回
Pure de Sitter space and the island moving back in time
论文作者
论文摘要
De Sitter空间中的观察者只能访问其宇宙学视野。假设有热平衡，我们使用量子ryu-takayanagi或Island公式来计算宇宙范围内部和外部状态之间的纠缠熵，作为时间的函数。我们获得了与Gibbons-Hawking熵相对应的值绑定的页面曲线。 在这种过渡时，“岛”形成了，与考虑黑洞的视野甚至及时移动时相比，该岛的位置在一个明显不同的位置。这些差异对于与纠缠楔的重建结合无关定理的非侵犯至关重要。此外，这种考虑还引入了争夺时间的需求，其熵依赖性与黑洞的期望相吻合。 我们采用的模型具有纯的三维设立空间作为解决方案。为了考虑半古典效应，我们在尺寸上缩小为两个维度。尽管如此，我们期望该岛的上述定性特征持续更高。
Observers in de Sitter space can only access the space up to their cosmological horizon. Assuming thermal equilibrium, we use the quantum Ryu-Takayanagi or island formula to compute the entanglement entropy between the states inside the cosmological horizon and states outside, as a function of time. We obtain a Page curve that is bound at a value corresponding to the Gibbons-Hawking entropy. At this transition an 'island' forms, which is in a significantly different location as compared to when considering black hole horizons and even moves back in time. These differences turn out to be essential for non-violation of the no-cloning theorem in combination with entanglement wedge reconstruction. This consideration furthermore introduces the need for a scrambling time, the entropy dependence of which turns out to coincide with what is expected for black holes. The model we employ has pure three-dimensional de Sitter space as a solution. We dimensionally reduce to two dimensions in order to take into account semi-classical effects. Nevertheless, we expect the aforementioned qualitative features of the island to persist in higher dimensions.
