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Matter is everywhere: we eat it, breathe it, drink it. It is who we are.
物質無處不在:我們吃它、呼吸它、喝它。它就是我們。
But what is matter?
但什麼是物質?
The most basic particle physics definition of matter comes down to one surprising rule:
最基本的粒子物理學對物質的定義,歸結為一條驚人的規則。
The Pauli exclusion principle - or, essentially, electrons hate being alike.
包立不相容原理 -- 或者說,從本質上講,電子討厭相似。
To understand why, we have to remember the fact that every electron is exactly the same.
要了解原因,我們必須記住一個事實,即每個電子都是完全一樣的。
Not "kind of the same"… They're perfectly identical.
不是「有點相同」…他們完全相同。
Just as you can at anytime, anywhere, spontaneously write down the number three and it will mean exactly, perfectly three.
就像你可以在任何時候、任何地方,自然而然地寫下數字三,它將意味著精確、完美的三。
As if there were some everywhere-permeating "three-ness" always available to produce a three at your whim.
彷彿有一些無處不在的「三性」,總是可以隨心所欲地產生三。
It's the same case with the electron.
這和電子的情況一樣:
There's an everywhere-permeating "electron-ness" called a "quantum field," and from that field every electron in existence has been summoned, and they are all, exactly, "electron".
有種無處不在的「電子性」稱為「量子場」,從這個場中召出的每一個電子都一樣是「電子」。
So when someone says "Every time you breathe, you inhale a few of the same electrons that used to be in Jesus or Mozart"
所以,當有人說「每次你呼吸時,你都會吸入一些曾經在耶穌或莫扎特體內的電子。」
That's about as deep as saying that every time you do arithmetic you use the same number three as Archimedes.
這就像在說,每次算術時,你和阿基米德用的數字三都是一樣的。
What's more?
還有呢?
Just like you can call on the "three-ness" to summon "negative-three", which has all the exact same properties of three except opposite.
你可以用「三性」衍生出「負三」,也就是和三擁有完全相同的特性,但與之相反。
And when it meets three they annihilate - you can summon "anti-electron" from the electron field and it will annihilate electron when they meet.
三和負三會互相抵銷,電子也一樣,你可以從電子場中召出「反電子」,而與電子相遇時,它們就會抵銷。
So, given that electrons are all exactly alike, it's a little surprising that they actually hate being like each other.
既然電子都是一模一樣的,那麼它們討厭彼此相像還挺令人驚訝的。
In fact, electrons despise alikeness so much that the universe is forbidden from summoning two or more into the same quantum state.
事實上,它們討厭彼此相像到宇宙裡沒有兩個或兩個以上量子處於同一個量子態中。
This is called "the Pauli Exclusion principle," and what it means in practice is that you can't cram too much matter into the same place – like a city where building higher than one story is prohibited:
這就是所謂的「包立不相容原理」,也就是不能放太多質量在同個地方,就像一個禁止建造高於一層建築城市。
Instead of skyscrapers, compounds sprawl outwards.
不是蓋摩天大樓,而是建築平面向外擴張。
So at the most fundamental level, matter is just any field, like "electron", "quark", or "neutrino" from which you can summon particles and anti-particles,
所以在最基本的層面上,物質只是任何體,比如「電子」、「夸克」或「中微子」,你可以從中召出粒子和反粒子。
but only one at every point, which means that, quite literally, matter is everything that takes up space.
但每次只能召喚一個,也就是說,物質就是一切佔用空間的東西。
Like Walmart.
比如沃爾瑪超市。