open the box, you surely know it is dead or alive.
before opening it, you never know it is dead or alive.
the moment you open the box, the many worlds becomes one world. that's the only world you can observe.
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"根据量子力学，未进行观察时，这个原子核处于已衰变和未衰变的叠加态，但是，如果在一个小时后把盒子打开，实验者只能看到“衰变的原子核和死猫”或者“未衰变的原子核和活猫”两种情况。"
".. after a while, the cat is simultaneously alive and dead. Yet, when we look in the box, we see the cat either alive or dead, not both alive and dead."
