原始问题：
The observable universe is finite; its boundary remains unseen.
The universe is an infinite space with no end. However, we can only see a portion of the observable universe, and the end of the observable universe is a place that we currently cannot observe.
The observable universe is finite; its boundary remains unseen.
https://www.aiaiask.com/ask/66761.html
Prev：我国在教育，科技和人才工作方面取得哪些突出的成就?