unobservable random variable

例句：

1. 1. The unobservable properties of the universe are still a subject of scientific inquiry.
   宇宙中不可观察的性质仍然是科学研究的对象。
2. 2. The unobservable behavior of quantum particles is what makes them so fascinating.
   量子粒子不可观察的行为是它们如此迷人的原因。
3. 3. The unobservable effects of climate change on the environment were not fully understood until recently.
   气候变化对环境不可观察的影响直到最近才被完全理解。