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

140,634 views ・ 2011-06-03

TED


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翻译人员: Bear Jin 校对人员: Angelia King
00:15
This is a representation of your brain,
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这是大脑的描绘图。
00:18
and your brain can be broken into two parts.
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你的大脑可以被分为两个部分。
00:21
There's the left half, which is the logical side,
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左脑,主要负责理性方面,
00:23
and then the right half,
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而右脑,
00:25
which is the intuitive.
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主要负责直觉。
00:27
And so if we had a scale to measure the aptitude of each hemisphere,
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如果我们用刻度线来测量脑半球的能力的话,
00:30
then we can plot our brain.
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并标记我们的大脑。
00:32
And for example, this would be somebody who's completely logical.
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比如说,这表示某人完全的理性。
00:35
This would be someone who's entirely intuitive.
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这就表示着某人完全的感性。
00:39
So where would you put your brain on this scale?
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那你会把你的大脑放在线上的哪里呢?
00:42
Some of us may have opted for one of these extremes,
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一些人可能会选这极端情况的一种,
00:45
but I think for most people in the audience,
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但是我觉得大多数听众,
00:47
your brain is something like this --
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你的大脑位置应该大致像这样--
00:49
with a high aptitude in both hemispheres at the same time.
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两个脑半球同时有着很高的潜力。
00:52
It's not like they're mutually exclusive or anything.
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它们不太可能会互相的排斥或其他什么的。
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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我自认为是一个
00:59
along with most of the other experimental quantum physicists,
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和大多数其他的实验量子物理学家一样,
01:02
who need a good deal of logic
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有着很好的逻辑思维
01:04
to string together these complex ideas.
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能把那些复杂的想法串连起来。
01:06
But at the same time, we need a good deal of intuition
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但是同时,我们也需要一个好的直觉
01:09
to actually make the experiments work.
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让实验能切实的进行下去。
01:11
How do we develop this intuition? Well we like to play with stuff.
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那我们如何来提高这种直觉力呢?嗯我们喜欢研究东西。
01:14
So we go out and play with it, and then we see how it acts,
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我们本身研究和捣鼓东西,然后我们会看它怎么反应。
01:17
and then we develop our intuition from there.
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接着我们从中提升我们的直觉力。
01:20
And really you do the same thing.
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实际上你也做同样的事情。
01:22
So some intuition
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有一些你可能
01:24
that you may have developed over the years
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培养了很多年了的直觉
01:26
is that one thing is only in one place at a time.
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像一个事物只能同时出现在一个方位。
01:30
I mean, it can sound weird to think about
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我的意思是,这会很奇怪,要你去考虑一个事物可以
01:33
one thing being in two different places at the same time,
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同时出现在两个不同的地方,
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这种概念,你是后天培养的。
01:40
And I remember watching a kid playing on a car stop.
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我记得看到过一个小孩在阻车器上玩。
01:43
He was just a toddler and he wasn't very good at it, and he kept falling over.
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他还只是个学步而且并不擅长这个的小孩,他就一直摔倒。
01:46
But I bet playing with this car stop taught him a really valuable lesson,
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但是我打赌和阻车器玩耍给他上了很有价值的一课,
01:49
and that's that large things don't let you get right past them,
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就是大型的物体不会让你轻易的穿过,
01:53
and that they stay in one place.
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而且它们停留在一个地方。
01:56
And so this is a great conceptual model to have of the world,
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这是世上拥有的一个很具备概念性的模型,
01:59
unless you're a particle physicist.
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除非你是粒子物理学家。
02:01
It'd be a terrible model for a particle physicist,
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对于粒子物理学家这也会是一个很糟糕的模型,
02:03
because they don't play with car stops,
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因为他们不研究阻车器,
02:05
they play with these little weird particles.
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他们研究那些很小的奇怪的微粒。
02:08
And when they play with their particles,
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当他们研究他们的微粒的时候,
02:10
they find they do all sorts of really weird things --
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他们觉得他们在做各种真正奇怪的事情--
02:12
like they can fly right through walls,
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好像他们能穿墙,
02:15
or they can be in two different places at the same time.
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或者他们能同时出现在两个地方。
02:19
And so they wrote down all these observations,
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他们记录下这些发现的时候,
02:22
and they called it the theory of quantum mechanics.
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他们以此起名为量子力学理论。
02:26
And so that's where physics was at a few years ago;
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这就是几年前物理学的前沿;
02:29
you needed quantum mechanics
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你需要量子力学
02:31
to describe little, tiny particles.
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来描述细小,微小的粒子。
02:33
But you didn't need it
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但是你不需要它
02:35
to describe the large, everyday objects around us.
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来描述那些巨大的,周围日常的物体。
02:39
This didn't really sit well with my intuition,
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这并不很符合我的直觉认知,
02:42
and maybe it's just because I don't play with particles very often.
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也许是因为我不太时常研究微粒的缘故吧。
02:45
Well, I play with them sometimes,
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嗯,我还是有时候研究它们的,
02:47
but not very often.
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只是不太平常而已。
02:49
And I've never seen them.
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而且我也从来没有看到过它们。
02:51
I mean, nobody's ever seen a particle.
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我指,没人能看见微粒。
02:54
But it didn't sit well with my logical side either.
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但是这也不符合我的逻辑认知。
02:57
Because if everything is made up of little particles
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因为如果所有事物都是由微粒组成的
03:00
and all the little particles
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而每个微粒
03:02
follow quantum mechanics,
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都遵循量子力学理论的话,
03:04
then shouldn't everything just follow quantum mechanics?
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那所有事物不也应该遵循量子力学理论吗?
03:09
I don't see any reason why it shouldn't.
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我找不到为什么它不遵循的原因。
03:12
And so I'd feel a lot better about the whole thing
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所以我对于整件事情会了解的更好
03:14
if we could somehow show
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如果我们用某种方式来表明
03:16
that an everyday object
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日常的每件事物
03:18
also follows quantum mechanics.
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也都遵循量子力学理论。
03:20
So a few years ago, I set off to do just that.
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不久之前,我开始着手。
03:23
So I made one.
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我制造出了这个。
03:26
This is the first object
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这是第一个你能看的见
03:28
that you can see
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同时也是
03:30
that has been in a mechanical quantum superposition.
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量子力学叠加的产物。
03:33
So what we're looking at here
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这里我们看到的
03:35
is a tiny computer chip.
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是一个电脑微型芯片。
03:37
And you can sort of see this green dot right in the middle.
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在中间你大概能看到的那个绿点。
03:40
And that's this piece of metal I'm going to be talking about in a minute.
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那就是我接下去要讲的金属。
03:43
This is a photograph of the object.
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这是它的照片。
03:45
And here I'll zoom in a little bit. We're looking right there in the center.
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聚焦一点。我们看到正中心的那点。
03:48
And then here's a really, really big close-up of the little piece of metal.
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这则是一个很近,很近距离观测到的金属片。
03:51
So what we're looking at is a little chunk of metal,
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我们看到的是一小块金属,
03:53
and it's shaped like a diving board, and it's sticking out over a ledge.
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它的外形像一个跳水板,并且它伸出了一端。
03:56
And so I made this thing
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我用几乎和制造电脑芯片
03:58
in nearly the same way as you make a computer chip.
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同样的方法制造出这金属。
04:00
I went into a clean room with a fresh silicon wafer,
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我在无菌室操作一片硅晶片,
04:03
and then I just cranked away at all the big machines for about 100 hours.
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接着我周转于所有这些大型机器中大约100个小时。
04:06
For the last stuff, I had to build my own machine --
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为了最后的结果,我不得不制造自己的机器--
04:08
to make this swimming pool-shaped hole
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让这泳池型的洞
04:11
underneath the device.
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在设备的下方。
04:13
This device has the ability
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这个设备有能力
04:15
to be in a quantum superposition,
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来进行量子叠加,
04:17
but it needs a little help to do it.
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但是它需要些帮助来完成这步骤。
04:19
Here, let me give you an analogy.
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来,让我给你打个比方。
04:21
You know how uncomfortable it is to be in a crowded elevator?
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你知道在一个拥挤的电梯里是多么不舒服吗?
04:24
I mean, when I'm in an elevator all alone, I do all sorts of weird things,
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我指,当我一个人在电梯里,我能做各种奇怪的事情,
04:27
but then other people get on board
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但是当其他人进来的时候
04:29
and I stop doing those things
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我就停止做这些事,
04:31
because I don't want to bother them,
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因为我不想打扰到其他人,
04:33
or, frankly, scare them.
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或者,实话说,吓到其他人。
04:36
So quantum mechanics says
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所以量子力学表明
04:38
that inanimate objects feel the same way.
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非生命体也变现出同样的情况。
04:41
The fellow passengers for inanimate objects
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那些非生命体的乘客
04:43
are not just people,
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不仅仅是人,
04:45
but it's also the light shining on it
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但是它还包括照射它的光
04:47
and the wind blowing past it and the heat of the room.
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吹拂过它的风和空间内的热度。
04:50
And so we knew, if we wanted to see
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所以,如果我们想目睹
04:52
this piece of metal behave quantum mechanically,
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这片金属表现出量子力学的特性,
04:55
we're going to have to kick out all the other passengers.
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我们就不得不剔除所有其他的乘客。
04:57
And so that's what we did.
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这就是我们曾做的。
04:59
We turned off the lights,
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我们关闭灯光,
05:01
and then we put it in a vacuum and sucked out all the air,
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接着我们把它放入抽真空机中并抽出所有的空气,
05:03
and then we cooled it down
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接着我们将它冷却
05:05
to just a fraction of a degree above absolute zero.
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到绝对零度以上一点点。
05:07
Now, all alone in the elevator,
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现在,在电梯里,
05:09
the little chunk of metal is free to act however it wanted.
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小金属片可以做任何它想做的事。
05:11
And so we measured its motion.
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我们测量了它的运动。
05:13
We found it was moving in really weird ways.
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我们发现它用很古怪的方式在运动。
05:15
Instead of just sitting perfectly still, it was vibrating,
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它是在震动,而不是完全的静止。
05:18
and the way it was vibrating was breathing something like this --
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它震动的方式是像这种--
05:21
like expanding and contracting bellows.
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像一张一合的风箱。
05:23
And by giving it a gentle nudge,
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只要给它一个轻微的撞击,
05:25
we were able to make it both vibrate
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我们就能让它震动
05:27
and not vibrate
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的同时
05:29
at the same time --
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也不震动--
05:31
something that's only allowed with quantum mechanics.
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某些只在量子力学范围下才会发生的事。
05:34
So what I'm telling you here is something truly fantastic.
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我在这里告诉大家的是一些很奇妙的事情。
05:37
What does it mean for one thing
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一个事物震动的
05:39
to be both vibrating and not vibrating
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同时也不震动
05:41
at the same time?
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这是什么意思?
05:43
So let's think about the atoms.
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让我们考虑下原子。
05:45
So in one case:
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一个例子:
05:47
all the trillions of atoms that make up that chunk of metal
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所有万亿个形成金属片的原子
05:50
are sitting still
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正保持静止
05:52
and at the same time those same atoms
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同时同样的这些原子
05:54
are moving up and down.
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正在上下移动。
05:56
Now it's only at precise times when they align.
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只有在特定精确时间,它们是一致的。
05:59
The rest of the time they're delocalized.
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余下的时间它们则是不定域的。
06:01
That means that every atom
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这意味着每个原子
06:03
is in two different places at the same time,
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在同一时间在两个不同的地方,
06:05
which in turn means the entire chunk of metal
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进一步说明整个金属片
06:08
is in two different places.
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在两个位置。
06:10
I think this is really cool.
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我认为这个真的很酷。
06:12
(Laughter)
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(笑声)
06:14
Really.
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真的。
06:16
(Applause)
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(掌声)
06:19
It was worth locking myself in a clean room to do this for all those years
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我这些年把自己锁在无菌室所做的事都是很值得的。
06:24
because, check this out,
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因为,看这个,
06:26
the difference in scale
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单个原子
06:28
between a single atom and that chunk of metal
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和金属片的比例差
06:30
is about the same as the difference
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大约和整片金属片和你这个个体的
06:32
between that chunk of metal and you.
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比例差是一样的。
06:34
So if a single atom can be in two different places at the same time,
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所以如果单个原子能同时处于不同的两个位置,
06:37
that chunk of metal can be in two different places,
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那金属片也能处于不同的两个位置,
06:40
then why not you?
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那么为什么你不能呢?
06:42
I mean, this is just my logical side talking.
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我指的,这只是我的理性思考的逻辑。
06:46
So imagine if you're in multiple places at the same time,
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那想想如果你能同时处于多个位置,
06:50
what would that be like?
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那会是什么样子的?
06:53
How would your consciousness
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你的认知将如何处理
06:55
handle your body being delocalized in space?
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你自身在空间中的不定域问题呢?
06:59
There's one more part to the story.
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这是故事的一个部分。
07:01
It's when we warmed it up,
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当我们把它加热,
07:03
and we turned on the lights and looked inside the box,
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并打开灯光观察盒子里面的时候,
07:06
we saw that the piece metal was still there in one piece.
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我们看到金属片依旧只是一块。
07:10
And so I had to develop this new intuition,
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所以我不得不形成一个新的直觉,
07:13
that it seems like all the objects in the elevator
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似乎所有电梯中的物体
07:16
are really just quantum objects
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实际上都被塞进一个极小空间中的
07:18
just crammed into a tiny space.
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量子物体。
07:20
You hear a lot of talk
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大家听过很多
07:22
about how quantum mechanics says that everything is all interconnected.
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关于量子物理学如何解释万物是互相联系的。
07:25
Well, that's not quite right.
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嗯,这不是完全正确的;
07:27
It's more than that; it's deeper.
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它要比这个更广泛,更深奥。
07:30
It's that those connections,
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正是这些联系,
07:32
your connections to all the things around you,
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你和你周边的这些联系,
07:35
literally define who you are,
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真正的定义了你是谁。
07:38
and that's the profound weirdness of quantum mechanics.
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这才是量子力学的深奥和不可思议。
07:41
Thank you.
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谢谢
07:43
(Applause)
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(掌声)
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