translation.en: There's another issue, which is that the forces in nature -- it's quite beautiful, actually -- seem, as you go back in time, they seem to change in strength.
translation.zh: 这是另外一个课题 就是自然力——这个现象非常奇妙—— 当你回到过去，就能看到 它们的力度会随着时间推移而变化