Aaron O'Connell: Making sense of a visible quantum object

140,634 views ・ 2011-06-03

TED


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譯者: Joan Liu 審譯者: Ana Choi
00:15
This is a representation of your brain,
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這是一個代表你大腦的圖像。
00:18
and your brain can be broken into two parts.
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而你的大腦可以分成兩個部分。
00:21
There's the left half, which is the logical side,
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左半邊,這是掌控邏輯的一邊,
00:23
and then the right half,
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然後是右半邊,
00:25
which is the intuitive.
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它掌控直覺。
00:27
And so if we had a scale to measure the aptitude of each hemisphere,
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所以如果我們有一個尺度去衡量這兩邊,
00:30
then we can plot our brain.
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那麼我們可以繪製我們的大腦。
00:32
And for example, this would be somebody who's completely logical.
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譬如,這是一個完全靠邏輯的人的大腦。
00:35
This would be someone who's entirely intuitive.
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這個人是完全直觀。
00:39
So where would you put your brain on this scale?
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那麼,你會把你的大腦放在這個尺上的哪裡?
00:42
Some of us may have opted for one of these extremes,
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有些人可能會選擇其中一個極端,
00:45
but I think for most people in the audience,
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但我認為,對大多數在台下的人,
00:47
your brain is something like this --
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你們的大腦是這樣的 --
00:49
with a high aptitude in both hemispheres at the same time.
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兩個腦半球同時有著很高的潛力。
00:52
It's not like they're mutually exclusive or anything.
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不是說它們會互相排斥或什麼的。
00:54
You can be logical and intuitive.
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你可以既理性又感性。
00:56
And so I consider myself one of these people,
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我自認為是一個和很多
00:59
along with most of the other experimental quantum physicists,
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其他的量子物理學家一樣,
01:02
who need a good deal of logic
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有很好的邏輯思維
01:04
to string together these complex ideas.
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能把這些複雜的想法串連起來。
01:06
But at the same time, we need a good deal of intuition
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但同時,我們也需要很好的直覺
01:09
to actually make the experiments work.
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讓實驗能切實的進行下去。
01:11
How do we develop this intuition? Well we like to play with stuff.
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我們如何啟發這種直覺呢?嗯,我們喜歡研究東西。
01:14
So we go out and play with it, and then we see how it acts,
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所以我們會去研究東西,然後我們會看它怎麼反應。
01:17
and then we develop our intuition from there.
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接著我們從中提升我們的直覺力。
01:20
And really you do the same thing.
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實際上你也做同樣的事情。
01:22
So some intuition
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所以有一些直覺,
01:24
that you may have developed over the years
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你可能培養了很多年,
01:26
is that one thing is only in one place at a time.
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像一個事物只能同時出現在一個方位。
01:30
I mean, it can sound weird to think about
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我的意思是,這聽起來很奇怪去考慮
01:33
one thing being in two different places at the same time,
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一個事物可以同時出現在兩個不同的地方,
01:37
but you weren't born with this notion, you developed it.
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但是你不是天生就有這種概念,你是後天培養的。
01:40
And I remember watching a kid playing on a car stop.
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我記得看到過一個小孩在阻車器上玩。
01:43
He was just a toddler and he wasn't very good at it, and he kept falling over.
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他還只是個小朋友,而且非常不擅長玩這個,他一直摔倒。
01:46
But I bet playing with this car stop taught him a really valuable lesson,
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但是我打賭跟阻車器玩耍給他上了很有價值的一課,
01:49
and that's that large things don't let you get right past them,
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就是大型的物體不會輕易的讓你穿過,
01:53
and that they stay in one place.
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而且它們停留在一個地方。
01:56
And so this is a great conceptual model to have of the world,
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這是世上擁有的一個很具備概念性的模型,
01:59
unless you're a particle physicist.
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除非你是粒子物理學家。
02:01
It'd be a terrible model for a particle physicist,
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對於粒子物理學家這會是一個很糟糕的模型,
02:03
because they don't play with car stops,
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因為他們不研究阻車器,
02:05
they play with these little weird particles.
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他們研究那些很小的奇怪微粒。
02:08
And when they play with their particles,
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當他們研究這些微粒的時候,
02:10
they find they do all sorts of really weird things --
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他們發現他們都在做各種很奇怪的事情--
02:12
like they can fly right through walls,
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比如他們能穿牆,
02:15
or they can be in two different places at the same time.
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或者他們能同時出現在兩個地方。
02:19
And so they wrote down all these observations,
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他們寫下這些觀察記錄,
02:22
and they called it the theory of quantum mechanics.
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然後他們把它起名為量子力學理論。
02:26
And so that's where physics was at a few years ago;
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而幾年前的物理學就是這樣;
02:29
you needed quantum mechanics
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你需要量子​​力學
02:31
to describe little, tiny particles.
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來描述細小,微小的粒子。
02:33
But you didn't need it
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但是你不需要
02:35
to describe the large, everyday objects around us.
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它來描述那些巨大的、生活周遭的尋常物體。
02:39
This didn't really sit well with my intuition,
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這並不是很符合我的直覺認知,
02:42
and maybe it's just because I don't play with particles very often.
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也許只是因為我不太時常研究微粒的緣故吧。
02:45
Well, I play with them sometimes,
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我有時候也會玩這些,
02:47
but not very often.
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但不是常常。
02:49
And I've never seen them.
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而且我從來沒有看過他們。
02:51
I mean, nobody's ever seen a particle.
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我的意思是,沒有人看過這些微粒。
02:54
But it didn't sit well with my logical side either.
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但這跟我的理性不大相符。
02:57
Because if everything is made up of little particles
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因為如果所有東西都是由微小微粒組成的
03:00
and all the little particles
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而且所有微粒
03:02
follow quantum mechanics,
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都遵守量子力學,
03:04
then shouldn't everything just follow quantum mechanics?
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那不是所有東西都應該符合量子力學嗎?
03:09
I don't see any reason why it shouldn't.
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我看不出為什麼不會。
03:12
And so I'd feel a lot better about the whole thing
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所以我覺得
03:14
if we could somehow show
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如果能夠讓
03:16
that an everyday object
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周遭所有東西都遵守量子物理
03:18
also follows quantum mechanics.
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會讓我覺得更好過一點。
03:20
So a few years ago, I set off to do just that.
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所以在幾年前,我開始這麼做。
03:23
So I made one.
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所以我製造了一個東西。
03:26
This is the first object
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這是第一個
03:28
that you can see
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你可以看得見
03:30
that has been in a mechanical quantum superposition.
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且可以表現得如量子力學解釋那樣。
03:33
So what we're looking at here
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所以我們這裡看到的是
03:35
is a tiny computer chip.
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一個很小的電腦晶片。
03:37
And you can sort of see this green dot right in the middle.
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而且你可以稍微看到這中間的綠點。
03:40
And that's this piece of metal I'm going to be talking about in a minute.
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那就是我接下來要講的金屬。
03:43
This is a photograph of the object.
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這是這個物件的照片。
03:45
And here I'll zoom in a little bit. We're looking right there in the center.
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放大一些看。我們現在看到的是在正中間。
03:48
And then here's a really, really big close-up of the little piece of metal.
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這是非常非常接近地看這塊小金屬。
03:51
So what we're looking at is a little chunk of metal,
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所以我們看到的是這塊小金屬,
03:53
and it's shaped like a diving board, and it's sticking out over a ledge.
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它的形狀像潛水板,而且它的周圍稍微凸出一些。
03:56
And so I made this thing
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我用製造電腦晶片幾乎一樣的手法
03:58
in nearly the same way as you make a computer chip.
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製作這個東西。
04:00
I went into a clean room with a fresh silicon wafer,
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我拿一個矽晶圓進到一個無塵室,
04:03
and then I just cranked away at all the big machines for about 100 hours.
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然後跟那些機器工作了大約一百個小時。
04:06
For the last stuff, I had to build my own machine --
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在最後的時候,我自己做了一個機器
04:08
to make this swimming pool-shaped hole
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來製造下方這個
04:11
underneath the device.
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游泳池形狀的洞。
04:13
This device has the ability
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這個器具
04:15
to be in a quantum superposition,
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可以在量子的形態存在,
04:17
but it needs a little help to do it.
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但它需要經過一些加工。
04:19
Here, let me give you an analogy.
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現在,讓我給你們一個比喻。
04:21
You know how uncomfortable it is to be in a crowded elevator?
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像是在很擠的電梯裡會感到不適,
04:24
I mean, when I'm in an elevator all alone, I do all sorts of weird things,
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我的意思是,當我自己一個人在電梯時,我會做很多奇怪的事,
04:27
but then other people get on board
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但當有其它人進到電梯時,
04:29
and I stop doing those things
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我停止做這些事,
04:31
because I don't want to bother them,
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因為我不想要打擾他們,
04:33
or, frankly, scare them.
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或是說嚇壞他們。
04:36
So quantum mechanics says
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所以量子力學說,
04:38
that inanimate objects feel the same way.
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無生命物體也這麼認為。
04:41
The fellow passengers for inanimate objects
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對無生命物體來說,
04:43
are not just people,
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乘客不只是人,
04:45
but it's also the light shining on it
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也包括了光源、
04:47
and the wind blowing past it and the heat of the room.
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風和房間裡的熱。
04:50
And so we knew, if we wanted to see
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所以我們知道,如果我們想要看
04:52
this piece of metal behave quantum mechanically,
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這塊金屬以量子力學的方式呈現,
04:55
we're going to have to kick out all the other passengers.
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我們需要把所有乘客都趕出去。
04:57
And so that's what we did.
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我們就是這麼做的。
04:59
We turned off the lights,
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我們把燈關掉,
05:01
and then we put it in a vacuum and sucked out all the air,
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然後用吸塵器把氣體吸掉,
05:03
and then we cooled it down
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然後讓它冷卻
05:05
to just a fraction of a degree above absolute zero.
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至比絕對零度高好幾分之一的溫度。
05:07
Now, all alone in the elevator,
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現在,自己一個在電梯裡,
05:09
the little chunk of metal is free to act however it wanted.
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這個小金屬可以做任意的事。
05:11
And so we measured its motion.
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所以我們量測它的活動。
05:13
We found it was moving in really weird ways.
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我們發現它以奇怪的方式運動。
05:15
Instead of just sitting perfectly still, it was vibrating,
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它沒有靜止不動,而是在震動。
05:18
and the way it was vibrating was breathing something like this --
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而且它震動的方式是有點像這樣的:
05:21
like expanding and contracting bellows.
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像是吸氣吐氣的風箱。
05:23
And by giving it a gentle nudge,
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當我們給它一點能量,
05:25
we were able to make it both vibrate
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我們能夠使它同時震動
05:27
and not vibrate
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及不震動
05:29
at the same time --
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在同一時間 --
05:31
something that's only allowed with quantum mechanics.
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這只有在量子物理中是被容許的。
05:34
So what I'm telling you here is something truly fantastic.
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所以我在這裡告訴大家的這是一件真的奇妙的事情。
05:37
What does it mean for one thing
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一個東西
05:39
to be both vibrating and not vibrating
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的同時在震動也不震動,
05:41
at the same time?
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這是什麼意思?
05:43
So let's think about the atoms.
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讓我們考慮一下原子。
05:45
So in one case:
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舉例而言:
05:47
all the trillions of atoms that make up that chunk of metal
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所有萬億個形成金屬片的原子
05:50
are sitting still
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正保持靜止狀態
05:52
and at the same time those same atoms
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然後在此同時,同樣的這些原子
05:54
are moving up and down.
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正在上下移動。
05:56
Now it's only at precise times when they align.
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只有在特定精確時間,它們是一致的。
05:59
The rest of the time they're delocalized.
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餘下的時間它們則是不定域的。
06:01
That means that every atom
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這意味著每個原子
06:03
is in two different places at the same time,
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在同一時間在兩個不同的地方,
06:05
which in turn means the entire chunk of metal
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進一步說明整個金屬片
06:08
is in two different places.
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在兩個位置。
06:10
I think this is really cool.
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我認為這真的很酷。
06:12
(Laughter)
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(笑聲)
06:14
Really.
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真的。
06:16
(Applause)
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(鼓掌)
06:19
It was worth locking myself in a clean room to do this for all those years
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我這些年把自己鎖在無菌室所做的事都是值得的。
06:24
because, check this out,
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因為,看看這個,
06:26
the difference in scale
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一個原子和一塊小金屬
06:28
between a single atom and that chunk of metal
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在尺度上的不同
06:30
is about the same as the difference
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就跟你和這塊小金屬的不同
06:32
between that chunk of metal and you.
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差不多。
06:34
So if a single atom can be in two different places at the same time,
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所以如果一個原子可以同時在兩個地方,
06:37
that chunk of metal can be in two different places,
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那塊金屬可以同時在兩個地方,
06:40
then why not you?
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那為什麼你不能?
06:42
I mean, this is just my logical side talking.
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我的意思是,這只是我的合理推測。
06:46
So imagine if you're in multiple places at the same time,
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所以想像你可以同時在不同的地方,
06:50
what would that be like?
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那會是怎麼樣的呢?
06:53
How would your consciousness
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你的意識
06:55
handle your body being delocalized in space?
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能夠接受你同時在不同地方嗎?
06:59
There's one more part to the story.
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這個故事還有另一個部份。
07:01
It's when we warmed it up,
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就是當我們給這個東西加熱,
07:03
and we turned on the lights and looked inside the box,
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且我們把燈打開來看這個盒子裡面,
07:06
we saw that the piece metal was still there in one piece.
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我們看到那塊金屬還是在那裡的。
07:10
And so I had to develop this new intuition,
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所以我必須發展另一個直覺,
07:13
that it seems like all the objects in the elevator
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就是看起來像是電梯裡所有的東西
07:16
are really just quantum objects
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都是量子物體,
07:18
just crammed into a tiny space.
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只是放在一個狹小的空間裡。
07:20
You hear a lot of talk
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你們聽過很多說法
07:22
about how quantum mechanics says that everything is all interconnected.
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說量子力學是在說每個東西都有交互作用。
07:25
Well, that's not quite right.
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這並不是完全正確的;
07:27
It's more than that; it's deeper.
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應該說,是更深奧的。
07:30
It's that those connections,
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是這些交互作用,
07:32
your connections to all the things around you,
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你和你周圍東西的交互作用,
07:35
literally define who you are,
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事實上定義著你。
07:38
and that's the profound weirdness of quantum mechanics.
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而這正是量子力學奇怪的地方。
07:41
Thank you.
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謝謝。
07:43
(Applause)
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