Name: 如何發現奇怪的新粒子｜新興量子準粒子 (How To Discover Weird New Particles | Emergent Quantum Quasiparticles)
Uploaded: 2021-01-14T10:19:20.000Z
Duration: 3 min 14 s

Physicists love particles, and with good reason – almost everything in the universe

物理學家熱愛粒子，而且有好理由─宇宙中幾乎一切

is made up of particles, so the physicist’s approach to understanding the universe is

都由粒子組成，因此物理學家了解宇宙的方法

關係子句

to understand the particles that make it up. If you want to discover and catalogue new

便是了解其組成粒子。如果你想發現並記錄新粒子

particles (which physicists do), here are three approaches you can take.

(如同物理學家)，提供你三招可以用。

First, you can take old particles we already know stuff about and just stick them together

首先，你可以把已知的舊粒子組合起來

to build new *composite* particles. That’s what chemists and molecular biologists spend

形成新的複合粒子。這就是化學家和分子生物學家

a lot of their time doing, and it’s kind of like figuring out what you can build with

花很多時間在做的，有點類似讓你用樂高積木堆東西。

第二，你可以讓舊粒子非常暴力地互相撞擊，不管事

Second, you can smash old particles together with ever increasing violence, either hoping

想打散舊粒子成為其未知的組成，或想使

to break an old particle apart into previously unknown constituents or to excite a new particle

潛伏於量子場中的粒子出現。有時候這招管用

into existence from the quantum fields that underly all reality. Sometimes this works

且會撞出全新的宇宙基本組成，像夸克

and the smashing reveals an entirely new *fundamental* building block of the universe like quarks

或希格斯粒子。但大多時候這只會產生一團亂，一場

or the Higgs boson. But most of the time it just makes a big mess, an explosion of old

第三，你可以把舊粒子放到新環境， 導致它們產生不同行為，或把

Third, you can put old particles in new environments so that they behave differently, or put old

舊粒子用不同方式放在一起，使它們產生類似粒子的

particles together in new ways so that new particle-like behaviors emerge through their

例如，在某些晶體中，移動的粒子並非墊子本身，

For example, in certain crystals, the particles that move around are not electrons themselves

而是密集電子海中的空缺(電洞)。

but in fact holes or gaps in a densely packed sea of electrons.

或當你把特定材料冷卻到極低溫，自由電子開始

Or, when you make certain materials really really cold, free electrons in them stop acting

不像電子，開始集結成隊， 猶如缺乏原子核的奇異原子，在幾乎

like electrons and team up in pairs to act like weird electron-only atoms that move around

或當你把特定金屬冷卻，電子開始表現得像

Or when you make certain metals really cold, electrons in them start acting as if they

再如果你做張非常薄幾乎是二維的砷化鎵薄片，加上

Or if you make a super thin essentially 2-dimensional sheet of gallium arsenide with a perpendicular

垂直磁場、平行電子並極度冷卻，電子表現出

magnetic field and parallel electric field and make it really cold, electrons start behaving

as if they had an electric charge that’s a fraction of what they normally do.

或你強迫電子進入一維直線，那些在線上前進後退的

Or if you force electrons into a special 1-dimensional line, the particles that move back and forth

粒子開始表現得像拆解的電子，因此它們有些

along that line *look* like electrons, except separated so that some of them have the charge

有電荷沒有自旋，有些會自旋卻無電荷。

of an electron but no spin, while others have the spin but no charge.

或你把氦冷卻到極致，你會發現新出現的粒子行為就像

Or if you cool helium down super super cold, you’ll find emergent particles that behave

希格斯粒子！這些出現的希格斯粒子 在1973年首度發現，比其基本構成

like higgs bosons! These emergent higgs bosons were first discovered in 1973, 40 years before

在大強子對撞機中，以質子的暴力相撞法發現

the higgs boson fundamental particle was discovered at the Large Hadron Collider by violently

當然，在金屬電子海中出現的那些「粒子」

Of course, the particles that emerge when you put collections of electrons together

並不算宇宙的基本組成，但它們更是多樣、

in materials aren’t fundamental constituents of the universe, but they’re far more diverse

奇異、古怪又酷炫。不像搜尋已經存在於大自然中

and bizarre and weird and cool. And unlike searching for fundamental particles where

的粒子，必須等待並觀察；我們可以主動尋找並編錄

you just have to wait and see what nature has in store, we can actively find and curate

新生粒子，只要創造各種奇怪材料，其性質能夠提供

new emergent particles simply by making different weird materials that allow their emergent

讓它們現身的條件。 另外，帶有這些粒子的材料具有真實且深遠的

properties to come to life. Plus, materials with emergent particles have real and far-reaching

科技實用性：在電器、電腦晶片、磁浮列車

practical technological use: in electronics, computer chips, levitating high speed trains,

甚至大強子對撞機裡，用來發現希格斯粒子的

and even the magnets and detectors used to discover the higgs boson at the Large Hadron

本影片部分由Gordon and Betty Moore Foundation’s Emergent Phenomena

This video was supported in part by the Gordon and Betty Moore Foundation’s Emergent Phenomena

EPiQS 支持奇異電子材料上的發現導向的研究

in Quantum Systems Initiative. EPiQS supports discovery-driven research on novel electronic

並試圖刺激突破以徹底改變我們對

materials and aims to stimulate breakthroughs to fundamentally change our understanding

事物組成原則的理解。想要學習更多，請至Moore.org或

of the organizing principles of complex matter. To learn more, visit Moore.org or follow the