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  • Check this out

    看看這個!

  • I'm using this speaker to vibrate a petri dish containing silicon oil

    我在用這個音響來讓含有矽油的培養皿振動

  • Now if I take this toothpick and make a little droplet on the surface

    現在,如果我用這支牙籤,在表面上做出一個小液滴

  • the droplet will stay there, hovering above the surface

    液滴會在那裡逗留,徘徊在表面上

  • The droplet is actually bouncing

    液滴其實是在彈跳

  • and it will keep bouncing for a very long time

    並能持續彈跳很長一段時間

  • Now the reason for this is a little layer of air between the droplet and the surface

    現在,會有這層在空氣與液滴和油面之間的薄膜

  • And the droplets bouncing so rapidly that that layer never shrinks to about 100 nanometers

    和液滴彈跳如此迅速到該層永遠不會縮至約100奈米

  • Which is what it would take for the droplet to recombine with the oil

    是因為液滴會與油重組

  • Now, every time the droplet lands on the surface, it creates a wave

    現在,每一次液滴落在油面時,會造出一個波

  • But this is a special type of wave

    而且這是一種特殊類型的波

  • Driven by the vibration of the oil bath

    透過油的振動來驅動

  • It is a standing wave

    這是一個駐波

  • Meaning that it is not traveling out

    這意味著它不會跑進油裡

  • It's just oscillating up and down

    它只是上下擺動

  • So the droplet makes the wave

    所以液滴造成了那個波

  • And then it interacts with that wave on its next bounce

    然後它的下一次彈跳會與那個波相互影響

  • If the drop lands on one side of the wave, it is pushed forwards

    如果液滴只落在波的一側,他會被推著走

  • And as long as the bounce of the droplet remains synchronized with the wave

    只要液滴的彈跳依然與波形同步就會一直持續

  • It will keep landing on the front side of the wave getting pushed farther forwards

    它會繼續落在波的前側且被推得更遠

  • Droplets like these are known as "Walkers"

    像這些液滴被稱為“步行者”

  • The bouncing oil drops has been known about since the 1970s

    自1970年代以來,彈跳的油滴就是已知的了

  • But only recently has it been discovered that you can use these little droplets

    但直到最近才發現,你可以用這些小液滴

  • to replicate many of the strange phenomena of quantum mechanics

    來複製許多量子力學的怪現象

  • Now obviously this is not a quantum system, the droplets are about a millimeter in diameter

    現在很明顯,這不是一個量子系統,液滴直徑約一毫米

  • But you can think of the droplets like, uh, quantum particles, say electrons

    但是你可以這樣想,嗯,量子粒子液滴,例如電子

  • One experiment that captures the key features of quantum mechanics is the Double-Slit Experiment

    捕獲量子力學主要特點的實驗是雙狹縫實驗

  • If you send a beam of electrons at two narrow slits

    如果向兩個狹窄的縫發送電子束

  • Well, the electrons, rather than behaving like particles and ending up in two clumps behind the slits

    那麼,電子不會只落在窄縫後的兩個區域

  • They produce an interference pattern

    它們會產生的干涉圖樣

  • Even when you send each electron through one at a time

    即使你一次只讓一個電子通過

  • With Walking droplets, the pilot wave goes through both slits

    因為液滴在走動,兩個縫隙導航波都會經過

  • Interfering with itself, while the droplet only goes through one slit

    與自身形成干擾,但液滴只會經過一個狹縫

  • The droplet does move in a straight line though

    液滴並以直線移動

  • It's deflected by its interaction with the wave

    是因為它與波相互影響而偏轉

  • The resulting distribution of where the droplets end up

    液滴最後產生出來的分布

  • Looks very similar to quantum double-slit interference patterns

    看起來與量子雙縫干涉圖樣非常相似

  • Or take tunneling

    或穿隧效應

  • In quantum mechanics, it's possible for a particle to get through a barrier

    在量子力學中,粒子有可能穿過障礙物

  • that it wouldn't classically have enough energy to get over

    它一般不會有足夠的能量來穿越

  • This has been demonstrated with Walkers by

    這已經由這些步行者證明

  • creating a shallow barrier under the surface of the oil

    油的表面下創建一個淺屏障

  • Usually the barrier reflects the pilot wave and its bouncing droplet

    通常屏障會反彈導航波和液滴

  • But in rare cases, the droplet does cross the boundary

    但是,在極少數情況下,液滴的確會穿過

  • And the probability of the droplet crossing the barrier

    而液滴穿越屏障的概率

  • Decreases exponentially with increasing width of the barrier, just as in quantum tunneling

    隨著屏障的寬度,就像在量子穿隧的指數下降

  • Perhaps the most surprising thing about these Walkers is they exhibit quantization, just like electrons bound to atoms

    或許,這些步行者最令人驚奇的是, 他們表現出的量化,就像原子中彈跳的電子

  • Here the Walker is confined to a circular corral

    在這裡,步行者被限制在一個圓形的圍欄

  • The droplet seems to move around randomly as it interacts with its pilot wave

    液滴似乎四處隨機移動,因為它與它的導航波相互影響

  • The complex interaction between the droplet and the wave leads to chaotic motion of the droplet

    液滴和波之間的複雜相互作用導致液滴的混亂運動

  • But over time, a pattern builds up

    但隨著時間的推移,慢慢建立了一個模式

  • This is the probability density of finding the droplet at any point within

    這是在圈內所有可能看到液滴的概率密度

  • the corral and it looks very similar to

    它看起來和電子的概率密度

  • the probability density of electrons

    非常相似

  • confined in a quantum corral

    當限制在量子圈中。

  • all of these similarities are no coincidence

    所有這些相似之處都不是巧合

  • the walking droplets actually create a

    走動的液滴事實上創造了

  • remarkable physical realization of a

    一個顯著的物理實現

  • theory proposed by de Broglie nearly a

    由德布羅意提出的理論

  • hundred years ago in the early days of

    在近一百年前,初期的

  • quantum mechanics he postulated that all

    量子力學,他推測所有

  • particles have a wave that accompanies

    粒子都伴隨著一個波

  • them and guides their motion and that

    並引導其運動而

  • wave is actually created by tiny

    那個波實際上是由微小

  • oscillations of the particle

    的粒子振動創造出來

  • Now this pilot wave theory was marginalized when

    這個導航波理論在當時被邊緣化

  • the standard Copenhagen interpretation

    當標準哥本哈根詮釋

  • became widely adopted

    為廣泛採用的時候

  • the Copenhagen interpretation excludes anything that

    哥本哈根詮釋排除任何

  • cannot be directly observed and it says

    不能直接觀察到的東西,它說

  • everything that can be known about a

    我們可以知道有關粒子

  • particle is contained in its so-called

    在它被所謂的

  • "Wave Function" but adopting this view

    “波函數”包含,但採用這種看法

  • forces you to give up on some common

    迫使你違反一些常識

  • sense notions like the idea that

    如一些概念,像是

  • particles have a definite position and

    粒子有一個確切的位置或動量,即使在沒有被測量的情況下

  • momentum even when they're not being measured

    它也意味著

  • and it also meant that the

    宇宙

  • universe was

    不再具有確定性

  • no longer deterministic

    隨機性建立了標準的量子力學

  • randomness is built into standard quantum mechanics

    拿雙狹縫實驗做舉例

  • for example take the double-slit experiment

    根據量子力學

  • according to quantum mechanics the wave

    電子的波函數是一個

  • function of the electron is a

    由電子同時通過

  • superposition of the electron going

    一個縫隙與另一個縫隙的疊合

  • through one slit and the other slip simultaneously

    使用此波函數可以計算出

  • using this wave function you can calculate the probability of

    電子可能會在哪裡出現的概率

  • where the electron is likely to be and

    然後當你在屏幕上偵測電子

  • then when you detected at the screen the

    它會在隨機一個點彈出

  • electron pops up at one point at random

    而結果分布會一樣,我們可以說

  • that was in that distribution we say

    波函數塌縮在

  • that its wave function collapses

    測量的瞬間

  • instantaneously at the moment of

    而不能說那個電子

  • measurement you can't say that the

    在你測量之前就在那裡了

  • electron was there before you measured

    甚至不能說

  • it and you can't even say that the

    電子必須通過一個狹縫

  • electron must have gone through one slit

    或其他的狹縫

  • or the other

    與由彈跳液滴

  • compare that with the picture provided

    所顯示出的圖片比較,這個情況下

  • by the bouncing droplets in this case

    導航波通過兩個縫隙

  • the pilot wave goes through both slits

    但液滴只通過一個

  • but the droplet only goes through one

    液滴被它自己的波相互影響而

  • the droplet is pushed around by its

    推著走,所以

  • interaction with the wave so that the

    這個分佈結果統計是

  • resulting statistical distribution is

    一模一樣的,液滴不會同時出現

  • the same the droplet never exists in two

    在兩個地方,也沒有隨機性。

  • places at once and there's no randomness

    如果有任何的不確定性,只是

  • if there is any uncertainty it's just

    因為我們不知道發生了什麼事

  • due to our ignorance of what's going on

    它不是不存在,所以導航波

  • it's not that it doesn't exist so pilot

    的活動可以提供很多

  • wave dynamics can produce many of the

    相同的結果,就如同量子力學

  • same results as quantum mechanics does

    這意味著這是量子粒子

  • this mean that this is really what

    真的在做的事?

  • quantum particles are doing

    不是,但我認為它至少意味著

  • no but I think it'll at least suggest

    這是可能的,這些都是可能的動態

  • that this is possible these are possible

    可能導出從

  • dynamics that could lead to the

    量子力學理論中

  • statistics which are captured in the

    所獲得的統計

  • quantum mechanical theory and what's

    這吸引人的是它給了你一個

  • appealing about this is it gives you a

    清晰的概念,對於發生了什麼事

  • clear idea of what's going on you don't

    你不得不丟棄

  • have to abandon the idea that the

    宇宙具有確定性的想法,和

  • universe is deterministic and you get

    粒子有確切的位置或有確切的動量的想法

  • particles with definite position and momenta.

    我認為我們有

  • I think it's great that we have

    兩個為同樣的實驗互相競爭的理論是很好的。

  • two competing theories for the same

    而這兩個理論都讓你得

  • experiments and they both asked you to

    接受古怪的事物,只是為不同的古怪。

  • accept odd things just different odd

    而你可以選擇看哪個

  • things and it comes down to what you're

    比較適合你的,真的,不管你

  • comfortable with really whether you

    比較喜歡的哥本哈根詮釋是標準的量子力學

  • prefer the Copenhagen interpretation is standard quantum mechanics

    或者是導航波理論

  • or a pilot wave theory

    讓我從留言知道你怎麼想

  • let me know what you think in the

    你喜歡導航波

  • comments do you like the pilot waves I

    我是說..這絕對是一個非常有吸引力的

  • mean it's definitely a very appealing

    圖像是否符合現實

  • picture whether or not correspond to

    ,尚待觀察

  • reality that remains to be seen

    嘿,這集的Veritasium是被各位在Patreon上所贊助

  • Hey this episode of Veritasium was supported in part by viewers like you on Patreon

    和谷歌的Making & Science提倡,它是在

  • and by Google's Making & Science Initiative which seeks to

    激發人們去學習更多有關

  • inspire people to learn more about

    科學與追求自己的科學目標

  • science and pursue their science goals

    現在,我知道有人在本週末追求

  • now I know someone else who is pursuing

    他們的科學目標,

  • their science goals this weekend that is

    那就是德斯坦在他的"SmarterEveryDay"頻道

  • Destin over it Smarter Every Day he

    他和我基本上是在觀察相同的

  • and I were looking at basically the same

    現象,不同的是他在觀察水滴

  • phenomenon but he was looking at water

    和為什麼它們不會合併在一起

  • droplets and why they don't coalesce so

    如果你想看看它是如何運作的

  • if you want to see how that works and

    和它在宇宙中的作用,去看看

  • how it works in space go check it out on

    他的頻道"SmarterEveryDay"吧!

  • his channel over at Smarter Every Day

    和往常一樣感謝收看

  • and as always thanks for watching

    看著幀數只有一的彈跳

  • looking at only one frame per bounce you

    你可以看到液滴運動是如何

  • can see how the droplets motion is

    透過它的波有效的引導飄移

  • guided by the wave it's effectively

    而波仍然存在,即使

  • surfing on and the wave remains even if

    液滴已經消失了,

  • the droplet disappears has happened

    有時會發生,如果遇到一點點

  • sometimes if it encounters a little bit

    污垢

  • of dirt

    真正酷的東西是

  • what's really cool about this is the

    這個波會存儲有關

  • wave actually stores information about

    液滴到過哪裡的資訊

  • where the droplet has been.

    這是因為每次液滴彈跳

  • This is because every time the droplet bounces

    它就創造一個的圓波

  • it creates a new circular wave centered

    且以它現在的位置為中心,而那個波

  • on its present location and that wave

    附加在現有的波場表面上

  • adds to the existing wavefield on the

    所以當液滴移動時

  • surface so as the droplet moves the

    它創造的波不斷的附加上去,

  • waves it makes keep adding up, storing

    存儲著它到過那裡信息