We live in a vast universe, on a small wet planet, where billions of years ago single-celled life forms evolved from the same elements as all non-living material around them, proliferating and radiating into an incredible ray of complex life forms. All of this— living and inanimate, microscopic and cosmic— is governed by mathematical laws with apparently arbitrary constants. And this opens up a question: If the universe is completely governed by these laws, couldn’t a powerful enough computer simulate it exactly? Could our reality actually be an incredibly detailed simulation set in place by a much more advanced civilization?
我們生活在浩瀚宇宙中 一個又濕又小的星球上, 數十億年前, 在這裡,單細胞生命形式 從和它們周遭所有非生物 相同的元素演化出來, 激增擴散成了很了不起的 複雜生命形式。 這一切——從生命到無生命、 微觀到宇宙觀—— 都由任意常數的數學法則所掌管。 這就帶出了一個問題: 如果宇宙完全由這些法則所掌控, 一台夠強大的電腦是否能夠 精確地模擬出宇宙來? 我們的現實有沒有可能其實是 由更先進的文明 所創造的極細緻模擬?
This idea may sound like science fiction, but it has been the subject of serious inquiry. Philosopher Nick Bostrom advanced a compelling argument that we’re likely living in a simulation, and some scientists also think it’s a possibility. These scientists have started thinking about experimental tests to find out whether our universe is a simulation. They are hypothesizing about what the constraints of the simulation might be, and how those constraints could lead to detectable signs in the world. So where might we look for those glitches?
這個想法可能聽起來很科幻, 但它確實是被認真探究過的主題。 哲學家尼克博斯特倫 提出了令人深思的主張: 我們很可能住在模擬中, 有些科學家也認為這是有可能的。 這些科學家開始思考要做些實驗, 來求證我們的宇宙是否是個模擬。 針對模擬的常數 及那些限制式如何能導致 世界上可偵測到的徵兆, 他們都做了假設。 所以,我們應該到哪裡 去找那些程式異常?
One idea is that as a simulation runs, it might accumulate errors over time. To correct for these errors the simulators could adjust the constants in the laws of nature. These shifts could be tiny— for instance, certain constants we’ve measured with accuracies of parts per million have stayed steady for decades, so any drift would have to be on an even smaller scale. But as we gain more precision in our measurements of these constants, we might detect slight changes over time.
一個想法是:當執行模擬時, 隨著時間可能就會累積錯誤。 為了修正這些錯誤, 模擬者可以調整自然法則的常數。 這些改變可能很微小——比如, 針對某些常數,我們的測量 精準度可達百萬分之幾(ppm), 數十年來它們都很穩定, 所以任何偏移都必然是更小的尺度。 但,當我們對這些常數的 測量能夠更精準時, 我們可能會隨著時間 而偵測到微小的改變。
Another possible place to look comes from the concept that finite computing power, no matter how huge, can’t simulate infinities. If space and time are continuous, then even a tiny piece of the universe has infinite points and becomes impossible to simulate with finite computing power. So a simulation would have to represent space and time in very small pieces. These would be almost incomprehensibly tiny. But we might be able to search for them by using certain subatomic particles as probes. The basic principle is this: the smaller something is, the more sensitive it will be to disruption— think of hitting a pothole on a skateboard versus in a truck. Any unit in space-time would be so small that most things would travel through it without disruption— not just objects large enough to be visible to the naked eye, but also molecules, atoms, and even electrons and most of the other subatomic particles we’ve discovered.
另一個可以考慮的地方, 源自於「計算能力有限」的概念, 不論計算能力多大, 都不能模擬出無限大。 如果空間和時間是連續的, 那麼,即使是宇宙的一小部分, 也會有無限多點, 用有限的計算能力 是不可能模擬出來的。 所以,模擬就必須要用非常 微小的部分來代表空間和時間。 這些部分會幾乎小到不可思議。 但我們可能可以用 某些亞原子粒子當探針, 來尋找它們。 基本原則是:越小的東西 對於中斷就會越敏感—— 想想看,滑板和卡車 壓過一個坑的結果。 在空間-時間中的 任何單位都會小到 大部分的東西通過它們時 不會發生中斷—— 不僅是大到肉眼能看到的東西, 也包括分子、原子,甚至電子, 還有大部分我們發現的 其他亞原子粒子。
If we do discover a tiny unit in space-time or a shifting constant in a natural law, would that prove the universe is a simulation? No— it would only be the first of many steps. There could be other explanations for each of those findings. And a lot more evidence would be needed to establish the simulation hypothesis as a working theory of nature.
如果我們確實在空間-時間中 發現了一個小單位, 或者發現自然法則的常數改變, 那是否就證明宇宙是個模擬? 不——那只是許多步驟中的第一步。 上述這每一項發現 都可能有其他解釋。 需要更多證據才能讓 這個模擬的假設 成為行得通的自然理論。
However many tests we design, we’re limited by some assumptions they all share. Our current understanding of the natural world on the quantum level breaks down at what’s known as the planck scale. If the unit of space-time is on this scale, we wouldn’t be able to look for it with our current scientific understanding. There’s still a wide range of things that are smaller than what’s currently observable but larger than the planck scale to investigate.
不論我們設計多少實驗, 我們總是會被它們 共有的一些假設給限制。 目前,我們對於自然世界的 了解是到量子層級, 這種了解在普朗克單位時就失效了。 如果空間-時間用的是這種單位, 用我們目前的科學理解 是找不到它的, 還有很多東西都小到 目前無法觀察到, 但比普朗克單位還大, 這些都還有待研究。
Similarly, shifts in the constants of natural laws could occur so slowly that they would only be observable over the lifetime of the universe. So they could exist even if we don’t detect them over centuries or millennia of measurements. We're also biased towards thinking that our universe’s simulator, if it exists, makes calculations the same way we do, with similar computational limitations. Really, we have no way of knowing what an alien civilization’s constraints and methods would be— but we have to start somewhere.
同樣的,自然法則的 常數改變可能非常緩慢, 可能要花上宇宙 一生的時間才能觀察到。 所以即使我們做了 數百、數千年的測量 仍然偵測不到,它們也可能存在。 我們也有偏見,認為 我們的宇宙是個模擬器 (如果存在的話), 且它做計算的方式和我們一樣, 也有類似的計算限制。 其實,我們不可能知道 外星文明的限制和方法會是什麼—— 但總要有個起始點。
It may never be possible to prove conclusively that the universe either is, or isn’t, a simulation, but we’ll always be pushing science and technology forward in pursuit of the question: what is the nature of reality?
可能永遠無法肯定宇宙 到底是或不是模擬出來的, 但在追尋這個問題時, 我們總會一直將 科學和科技向前推進: 現實的本質是什麼?