But we can determine what that constant is, because we know that if we sum over all the possible states, the molecule has to be in some state, right?
我们可以确定这个常数，因为我们知道，当我们把所有的态加起来之后，粒子必定处于某个状态，对吗？
E So if we wrote E as we've seen in the past, it's just the sum over that energy times the probability for each state.
如果我们写,就像之前看到的，它就是各个状态的能量,乘以概率的和。
So we could say, let's not do the sum over every state.
也即是说我们并不是对每个状态求和。
And then realizing that the probability that some state out there has to be occupied, we saw that of course if we sum over all these probabilities that sum has to equal one, right?
并且我们知道，某个状态必定会被占据，那么这些概率相加，的结果应该等于一？
And then realizing that the probability that some state out there has to be occupied, we saw that of course if we sum over all these probabilities that sum has to equal one, right?
并且我们知道，某个状态必定会被占据，那么这些概率相加，的结果应该等于一？
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