玻尔兹曼大脑悖论
你怎么知道你是一个过着你生活的人，而不是一个刚刚形成的充满人工记忆的大脑，一时幻觉一个实际上并不存在的现实？这听起来可能很荒谬，但它让几代顶级宇宙学家彻夜难眠。他们称之为：玻尔兹曼大脑悖论。Fabio Pacucci 探索了这个令人麻木的思想实验。[由 Skirmanta Jakaitė 执导，Art Shot，Addison Anderson 旁白，Salil Bhayani 音乐，cAMP Studio]。
How do you know you’re a person who has lived your life, rather than a just-formed brain full of artificial memories, momentarily hallucinating a reality that doesn't actually exist? That may sound absurd, but it’s kept several generations of top cosmologists up at night. They call it the Boltzmann brain paradox.
你怎么知道你是一个过着你生活的人， 而不是一个刚刚形成的充满人工记忆的大脑， 暂时幻想着一个实际上并不存在的现实？ 这听起来可能很荒谬， 但它让几代顶级宇宙学家彻夜难眠。 他们称之为玻尔兹曼大脑悖论。
Its namesake, Ludwig Boltzmann, was a 19th century physicistoperating in a period when scientists were passionately debatingwhether the universe had existed for an infinite or finite time.Boltzmann’s main claim to fame was revolutionizing thermodynamics, the branch of physics that studies energy. He put forward a new interpretation of entropy, which is a measure of the disorder of a system. A glass is an ordered system, whereas a shattered glass is disordered. The second law of thermodynamics states that closed systems tend towards disorder: you won’t see a shattered glass return to its pristine state.
与它同名的路德维希·玻尔兹曼 (Ludwig Boltzmann) 是 19 世纪的物理学家 ，当时科学家们正在激烈地争论 宇宙是否存在了无限或有限的时间。 玻尔兹曼的主要声名是彻底改变热力学， 这是研究能量的物理学分支。 他提出了对熵的新解释，熵 是系统无序程度的度量。玻璃是有序的系统，而破碎的玻璃是无序的。 热力学第二定律指出，封闭系统倾向于无序： 你不会看到破碎的玻璃恢复到原始状态。
Boltzmann’s insight was applying statistical reasoning to this behavior. He found that a system evolves to a more disordered state because it’s more likely. However, the opposite direction isn’t impossible, just so unlikely that we’ll never witness things like scrambled eggs turning raw.
玻尔兹曼的见解是将统计推理应用于这种行为。 他发现一个系统进化到更无序的状态是因为它更有可能。 然而，相反的方向并非不可能， 只是不太可能，以至于我们永远不会看到像炒鸡蛋这样的东西变成生的。
But if the universe exists over an infinitely long time, extremely unlikely events will happen, including complex things forming out of random combinations of particles. So what does that look like in a hypothetical infinitely old universe? In this unremarkable stretch of near-nothingness, about eight octillion atoms randomly come together to form a replica of the Thinker made of pasta. It instantly dissolves. Over here, these particles suddenly form something like a brain. It’s filled with false memories of a lifetime up to the present moment, when it perceives a video saying these very words, before decaying. And finally, by random fluctuations, all the particles in the cosmos concentrate in a single point, and an entire new universe spontaneously bursts into existence. Of those last two, which is more likely? The brain, by far— despite all its complexity, it’s a blip compared to an entire universe. Every one universe produced by random fluctuations has equivalent odds to heaps upon heaps of insta-brains. So by this reasoning, it seems extremely more likely that everything you believe to exist is actually a brief illusion, soon to be extinguished.
但如果宇宙存在无限长的时间， 极不可能发生的事件就会发生， 包括由粒子随机组合形成的复杂事物。 那么在一个假设的无限古老的宇宙中，这是什么样的呢？ 在这片不起眼的近乎虚无中， 大约 8 个 octillion 原子随机聚集在一起，形成了 由意大利面制成的 Thinker 的复制品。 它立即溶解。 在这里，这些粒子突然形成了类似大脑的东西。 它充满了一生的虚假记忆，直到现在， 当它感知到一段视频说这些话， 然后才腐烂。 最后，通过随机波动，宇宙中的所有粒子 集中在一个点上， 一个全新的宇宙自发地爆发出来。 在最后两个中，哪个更有可能？ 到目前为止，大脑—— 尽管它很复杂，但与整个宇宙相比，它只是一个昙花一现。 由随机波动产生的每一个宇宙都有与 成堆的即时大脑相当的几率。 所以根据这个推理，你认为存在的一切似乎极有可能实际上是一个短暂的幻觉， 很快就会消失。
Boltzmann didn’t get quite that far in his thinking; the brains themselves were introduced by later cosmologists building on his work. But they, like just about everyone else, were pretty sure that they themselves weren't just ephemeral brains. So the paradox was: how could they be correct and the universe be eternal? The resolution is something most take for granted today:that our universe has not existed forever, but rather time and space started with a Big Bang.
玻尔兹曼的想法并没有走得那么远。 后来的宇宙学家在他的工作基础上介绍了大脑本身。 但他们和其他所有人一样， 非常确定他们自己不仅仅是短暂的大脑。 所以悖论是：它们怎么可能是正确的，而宇宙是永恒的？ 这个决议在今天是大多数人认为理所当然的事情：我们的宇宙并不是永远存在的， 而是时间和空间始于大爆炸。
So that’s the paradox over and done with, right? Well, maybe not.In the last century, scientists have found evidence supporting the theory of the Big Bang everywhere we look. Yet while we know that the Big Bang happened, no one knows what, if anything, preceded and caused it. Why did the universe begin in such an extremely ordered, and unlikely, state? Is our universe in an unending cycle of creation and collapse? Or might we be in one of many universes expanding within a multiverse?
所以这就是悖论了，对吧？ 好吧，也许不是。 在上个世纪，科学家们在我们所看到的任何地方都发现了支持 大爆炸理论的证据。 然而，虽然我们知道大爆炸发生了， 但没有人知道是什么（如果有的话）先于并导致了它。 为什么宇宙会以如此极其有序且不太可能的状态开始？ 我们的宇宙是否处于创造和崩溃的无休止循环中？ 或者我们可能处于在多元宇宙中扩展的众多宇宙之一？
In this context, Boltzmann’s paradox has found renewed interestby contemporary cosmologists. Some argue that leading models for where the universe came from still imply that Boltzmann brains are more likely than human brains, suggesting something’s amiss. Others counter that slight modifications of the cosmological models would avoid the problem, or that Boltzmann’s brains can’t actually physically form. Some researchers even attempted to calculate the probability of a brain popping out of random quantum fluctuations long enough to think a single thought. They got this incredible number whose denominator is 10 to a number about a septillion times largerthan the number of stars in the universe. The Boltzmann brain paradox, despite its absurdity, is useful because it creates a bar that models have to rise to. If, compared to numbers like this one,the current state of the universe is exceedingly unlikely,something in the model is almost certainly wrong. Unless you’re the one who is wrong...
在这种情况下，玻尔兹曼悖论重新引起 了当代宇宙学家的兴趣。 一些人认为，宇宙起源的主要模型 仍然暗示玻尔兹曼大脑比人类大脑更有可能， 这表明有些不对劲。 其他人则反驳说，对宇宙模型的轻微修改 可以避免这个问题， 或者说玻尔兹曼的大脑实际上无法形成物理形式。 一些研究人员甚至试图计算 大脑从随机量子波动中弹出足够长的时间来思考一个想法的概率。 他们得到了这个令人难以置信的数字 ，其分母是 10 到大约 septillion 倍的数字 比宇宙中恒星的数量还要多。 玻尔兹曼大脑悖论尽管很荒谬，但 很有用，因为它创造了模型必须达到的标准。 如果与这样的数字相比， 宇宙的当前状态极不可能， 那么模型中的某些东西几乎肯定是错误的。 除非你是错的人...
