量子力学揭秘（2014）（1）

但随时间推移 图案逐渐显现 形成了波特征的条纹
But gradually a pattern forms, the signature wave pattern.
让我再详细地说明一下这到底奇怪在哪
Let me be quite clear about just how weird this is.
回想之前的水箱波纹实验
Remember from the wave tank experiment
之所以最终波特征条纹的形成
where the signature wave pattern only exists
是因为每个波纹都同时穿过了两条狭缝
because each wave passes through both slits
并使其被分割的两部分相互干扰
and then its two pieces interfere with each other.
但现在 每个单独的电子
But here, every individual electron,
在达到屏幕之前 穿越过两个狭缝的
each single particle is passing alone through the slits
是其本身单独一个粒子
before it hits the screen.
而且即便如此 每个单独的电子仍然最终可以形成
And yet, each single electron is still contributing
波特征的条纹
to the signature wave pattern.
也就是说每个电子都必须具有波动性
Each electron has to be behaving like a wave.
为了解释这个奇怪的实验结果
To explain this strange result,
尼尔斯·玻尔和他的同事们创立了量子力学
Niels Bohr and his colleagues created quantum mechanics,
一套光与物质的疯狂理论 还夹杂着众多矛盾的观点
a crazy theory of light and matter that embraced contradiction
而并不关心这几乎不可能被理解的理论是否能被众人所接受
and didn't care that it was almost impossible to understand.
正如尼尔斯·玻尔所说
As Niels Bohr himself said,
任何没被量子力学所震惊的人都没能完全理解它
anyone who isn't shocked by quantum theory hasn't understood it.
那么 观众们 接下来我要用这小小的电子
So, viewers, I'm going to take our tiny electron
来深入探究实在的核心所在
and use it to delve deep into the heart of reality.
当然 要做好被震惊的准备
And, yes, prepared to be shocked
因为仅有通过这唯一的途径
because this is the only way to explain what we observe
才能解释当一个电子穿越狭缝到达屏幕时
when a single electron travels through the slits
所产生的结果
and hits the screen.
根据量子力学
Quantum mechanics says this...
我们不能把穿越过狭缝的物体形容为一个实体对象
..We can't describe what's travelling as a physical object.
我们唯一能说的是
All we can talk about
这些电子可能具有概率
are the chances of where the electron might be.
这种概论波以某种方式穿越两条狭缝
This wave of chance somehow travels through both slits
并形成干涉 就如同水波那样
producing interference just like the water wave.
当其达到屏幕时
Then when it hits the screen,
刚才那具有灵魂般概率的电子
what was just the ghostly possibility of an electron
又神秘地变回实体
mysteriously becomes real.
让我用一个类比试着阐述这有多么不可思议
Let me try and capture just how weird this is with an analogy.
如果我旋转这枚硬币
If I spin this coin...
那么只要它在旋转
Then all the time it's spinning, it's a blur,
我就无法分辨出头或尾
I can't tell if it's heads or tails
但是如果我把它挡住 强迫它做出抉择 是正
but if I stop it, I force it to decide and it's heads.
所以之前 它的状态似乎并不仅仅只是正和反的区分 而是两者的混合
So before it was sort of not heads or tails but a mixture of both
但是一旦我把它挡住
but as soon as I've stopped it,
我就强迫它做出了决定
I've forced it to make up its mind.
这就是玻尔和他的支持者们
This is what Bohr and his supporters
声称的电子的真实状态
claimed was happening with our electrons.
在某种意义上 当硬币旋转时 它可以同时处于正和反的状态
In a sense, as it spins, the coin is both heads and tails.
同样的 电子以概率波的形式
Similarly, the electrons' wave of chance
同时穿过两个狭缝
passes through both slits, two paths at the same time.
硬币停在了正的状态
Our coin then stops at heads.
只有在幽灵般的概率波到达屏幕之时
The ethereal wave of probability hits the screen
才变成了粒子
and only then becomes a particle.
量子的世界与我们所见到的一切都不相同
The quantum world was unlike anything ever seen before.
无论怎么夸张都不为过
It's hard to overstate just how crazy this is.
玻尔声称 在测量之前
Bohr was effectively claiming that one can never know
我们无法得知电子的确切位置
where the electron actually is at all until you measure it
还不仅仅只是无法得知电子位置
and it's not just that you don't know where the electron is,
更奇怪的是电子本身同时处于各处
it's weirdly as though the electron itself is everywhere at once.
请记住电子是现实世界
Bear in mind that electrons are among the commonest
最普遍 最根本的基石
and most basic building blocks of reality
然而玻尔却说只有通过观测
and yet here's Bohr saying that only by looking
我们才能使它们的位置变成真实存在
do we actually conjure their position into existence.
我们与量子世界之间似乎隔着一道帷幕
It's like there's a curtain between us and the quantum world
而在帷幕的后面 没有确定的实在
and behind it there is no solid reality...
只有可能的实在
..Just the potential for reality.
事情只有在我们拉开帷幕观察时 才变得真实
Things only become real when we pull back the curtain and look.
女士们先生们 而这个观点
And this view, ladies and gentlemen,
成了后人熟知的哥本哈根解释
became known as the Copenhagen interpretation.
尽管看起来很有说服力
Persuasive as it might seem,
很多人还是无法接受玻尔这荒诞不经的观点
many people couldn't stomach Niels Bohr's outlandish ideas.
但他们在科学界最具影响力的圈子里
And they found a natural leader
找到了作为他们领袖的绝佳人选
in the most powerful man in science.
阿尔伯特·爱因斯坦浑身每个细胞
Albert Einstein hated this interpretation
都对这种解释极度厌恶
with every fibre of his being.
他有一句非常著名的话
He famously said,
"我不看月亮的时候它就不存在吗"
"Does the moon cease to exist when I don't look at it?"
他极度不满 因为他认为这个解释
He was very unhappy because it gave limits to knowledge
为探寻最终答案的人们套上了枷锁
that he didn't think should be final.
他认为应该还存在一个更加根本的理论
He thought there should be a better underlying theory.
在接下来的十年中
Over the next ten years,
爱因斯坦和玻尔进行了激烈的争论
Einstein and Bohr would argue passionately
争论的焦点是
about whether quantum
量子力学是否意味着对实在的否定
mechanics meant giving up on reality or not.
紧接着 和另两位科学家纳森·罗森和鲍里斯·波多尔斯基一道
Then, with two other scientists, Nathan Rosen and Boris Podolsky,
爱因斯坦认为他们找到了赢得这场争论的途径
Einstein thought they'd found a way to win the argument.
他确信自己找到了哥本哈根解释以及它所
He was convinced he'd found a fatal flaw
声称的实在只有在经过观测之后
in the Copenhagen interpretation and it's claim that reality
才存在这一说法的致命缺陷
was summoned into existence by the act of looking at it.
爱因斯坦论点的核心
At the heart of Einstein's argument
是量子力学中的一个概念 纠缠
was an aspect of quantum mechanics called entanglement.
纠缠是一对命运相互交织的量子之间
Now, entanglement is this special, incredibly close relationship
那种特殊而又极其紧密的联♥系♥
between a pair of quantum particles whose fates are intertwined.
比如说 如果它们是在同一事件中产生的两个量子
For example, if they were created in the same event.
我会把这两个粒子当成
Let me try and explain this
两个旋转的硬币来试着解释这一现象
by imagining the two particles are spinning coins.
想象一下这两个硬币就是两个电子
Imagine these coins are two electrons
他们是同一事件中产生的 然后彼此分开
created from the same event and then moved apart from each other.
量子力学表明 因为他们是一起产生的
Quantum mechanics says that, because they're created together,
他们之间就发生了纠缠
they're entangled.
他们之间的一些特性就永远联结在了一起
And now many of their properties are for ever linked,
无论他们身处何方
wherever they are.
回想之前 哥本哈根解释说
Remember, the Copenhagen interpretation says that
除非你去测量这两个硬币
until you measure one of the coins,
否则它们就既非正也非反
neither of them is heads or tails.
事实上 正和反的概念都不会存在
In fact, heads and tails don't even exist.
而纠缠使
And here's where entanglement
这种奇怪的现象更加诡异
makes this weird situation even weirder.
当我们挡住第一个硬币让它变成正后
When we stop the first coin and it becomes heads...
由于这两个硬币因纠缠联结在一起
..Because the coins are linked through entanglement,
第二个硬币就会同时地变成反面
the second coin will simultaneously become tails.
更重要的一点是
And here's the crucial thing.
我无法预测我测量的结果如何
I can't predict what the outcome of my measurement will be,
只知道它们的状态会永远相反
only that they will always be opposite.
爱因斯坦抓住了这一点
Einstein seized on this.
因为这意味着
Because it meant that
这两个硬币之间的联♥系♥
something was happening between the two coins
太过诡异而无法想象
that was almost too crazy to imagine.
就好像两个硬币之间存在秘密的通信
It's as if the two coins are secretly communicating.
而这种通信能瞬间穿越时空
Communicating instantaneously across space and time.
即使这两个硬币一个在地球 另一个远在冥王星
Even if the first coin was on Earth and the other was on Pluto.
爱因斯坦拒绝相信
Einstein refused to believe
这种瞬时的 能超越光速的通信的存在
this instantaneous, faster-than-light communication.
他的相对论
His theory of relativity
正是表明没什么能比光速还快
said that nothing could travel that fast.
即使是信息也不能
Not even information.
那一个硬币怎么能瞬间就知道
So, how could one coin instantaneously know
另一个硬币的行为呢
how the other would land?
他轻蔑地称之为"超距幽灵"
He disparagingly called it "Spooky action at a distance"
并称这是哥本哈根解释中的一个致命缺陷
and claimed it was a fatal flaw in the Copenhagen interpretation.
而且 他有一个更好的解释
What's more, he had a better idea.
爱因斯坦相信存在一个更简明的解释
Einstein believed there was a simpler interpretation.
无论硬币最终是正是反
That somehow the destiny of the two coins, whether or not they
他们最终的状态
ended up heads or tails,