[season 01 episode 01]
Sheldon: So if a photon is directed through a plane with two slits in it and either slit is observed, it will not go through both slits. If it’s unobserved, it will. However, if it’s observed after it’s left the plane but before it hits its target, it won’t have gone through both slits.
Leonard: Agreed. what’s your point?
Sheldon: There’s no point, I just think it’s a good idea for a t-shirt.

Sheldon: 所以如果一个光子穿过一个有两条窄缝的挡板，如果两条窄缝中任何一条被观测，则光子不会同时穿过这两条窄缝。如果不观测则不然。但是，如果观测发生在光子离开挡板而未击中目标的时候，它不可能同时穿过两条裂隙。
Leonard: 同意。你想说什么？
Sheldon: 没什么。我只是觉得这个设计用在T恤上挺不错。

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