The phenomenon you saw here for a brief moment

稱作量子懸浮和量子鎖定。

is called quantum levitation and quantum locking.

而這個懸浮中的物體

And the object that was levitating here

是超導體。

is called a superconductor.

超導現象是物質的量子物理狀態，

Superconductivity is a quantum state of matter,

它只會在低於特定的溫度時發生。

and it occurs only below a certain critical temperature.

其實超導體現象存在已久；

Now, it's quite an old phenomenon;

大約在一百年前就被發現了。

it was discovered 100 years ago.

不過，

However, only recently,

依賴於最近的技術進步 (譯按:是說高溫超導體)

due to several technological advancements,

我們才可以在此展示

we are now able to demonstrate to you

量子懸浮和量子鎖定。

quantum levitation and quantum locking.

超導體具有兩種特徵。

So, a superconductor is defined by two properties.

其一是零電阻，

The first is zero electrical resistance,

其二是內部抗磁性。

and the second is the expulsion of a magnetic field from the interior of the superconductor.

聽起來很複雜,對嗎?

That sounds complicated, right?

何謂電阻?

But what is electrical resistance?

電力是電子在物質中流動,

So, electricity is the flow of electrons inside a material.

電子流動時會與原子碰撞，

And these electrons, while flowing,

而這些碰撞

they collide with the atoms, and in these collisions

會使電子失去部份能量

they lose a certain amount of energy.

失去的能量會轉換成為熱，此謂之電阻

And they dissipate this energy in the form of heat, and you know that effect.

可是，在超導體中不會有此類碰撞，

However, inside a superconductor there are no collisions,

於是沒有能量流失。

so there is no energy dissipation.

這相當不平常。試想想。

It's quite remarkable. Think about it.

在古典物理學界，摩擦與能量流失無處不在。

In classical physics, there is always some friction, some energy loss.

但因為這是量子物理現象，所以不存在摩擦和能量損失。

But not here, because it is a quantum effect.

除此之外，因為超導體不喜歡磁場，

But that's not all, because superconductors don't like magnetic fields.

超導體會通過使電流循環流動，

So a superconductor will try to expel magnetic field from the inside,

而從其內部盡量把磁場排除。

and it has the means to do that by circulating currents.

具備以上兩種特徵，

Now, the combination of both effects --

零電阻和內部抗磁性，

the expulsion of magnetic fields and zero electrical resistance --

就是超導體。

is exactly a superconductor.

大家知道，事情並不總是完美的，

But the picture isn't always perfect, as we all know,

有時候，一點點磁場會殘留在超導體內部。

and sometimes strands of magnetic field remain inside the superconductor.

在適當的條件下，就如這裡可見，

Now, under proper conditions, which we have here,

這些殘留的磁場會被困在超導體裡。

these strands of magnetic field can be trapped inside the superconductor.

而且這些殘留的磁場是離散量，

And these strands of magnetic field inside the superconductor,

即不是連續的。

they come in discrete quantities.

為什麼？ 因為這是量子現象，量子物理。

Why? Because it is a quantum phenomenon. It's quantum physics.

它的行為就如量子一樣。

And it turns out that they behave like quantum particles.

從影片可見，它一個個分開地移動。

In this movie here, you can see how they flow one by one discretely.

它是磁場，而非粒子，

This is strands of magnetic field. These are not particles,

但行為就如粒子一樣。

but they behave like particles.

這就是為什麼這個現象叫量子懸浮和量子鎖定。

So, this is why we call this effect quantum levitation and quantum locking.

若將超導體置入一個磁場中會發生甚麼事呢?

But what happens to the superconductor when we put it inside a magnetic field?

嗯，首先是我們知道還有一些游離的磁場殘留在其中，

Well, first there are strands of magnetic field left inside,

但是超導體不會讓他們隨便移動

but now the superconductor doesn't like them moving around,

因為移動就會有能量流失，

because their movements dissipate energy,

也就是說會破壞超導狀態。

which breaks the superconductivity state.

所以超導體此時就會將這幾束所謂的磁通量子（磁場束）鎖定

So what it actually does, it locks these strands,

將其固定在一個位置上

which are called fluxons, and it locks these fluxons in place.

如此一來，超導體自己也會被固定住。

And by doing that, what it actually does is locking itself in place.

為什麼呢?因為超導體的任何移動 都會改變這些磁通量子的位置，

Why? Because any movement of the superconductor will change their place,

也就改變了其格局。

will change their configuration.

這就是量子鎖定的由來。現在就讓我們來一探究竟，

So we get quantum locking. And let me show you how this works.

現在我這裡有一個超導體， 事前已經用液氮包了起來， 這樣它可以保持在低溫的狀態足夠久。

I have here a superconductor, which I wrapped up so it'd stay cold long enough.

當我將它放置在一個一般的磁鐵上時，

And when I place it on top of a regular magnet,

它就這樣鎖定在半空中。

it just stays locked in midair.

(掌聲)

(Applause)

現在，這既不僅是懸浮，也不僅是排斥作用。

Now, this is not just levitation. It's not just repulsion.

我可以改變這些磁通量子的位置，它會被鎖定在新的格局裡。

I can rearrange the fluxons, and it will be locked in this new configuration.

就像這樣，或者是讓它偏左或偏右一點。

Like this, or move it slightly to the right or to the left.

這就是量子鎖定--真正的鎖定--超導體的三維鎖定。

So, this is quantum locking -- actually locking -- three-dimensional locking of the superconductor.

當然，我也可以把這個鎖定的格局翻過來，

Of course, I can turn it upside down,

超導體仍然被鎖定在原來的位置。

and it will remain locked.

現在我們已經知道所謂的懸浮其實是鎖定，

Now, now that we understand that this so-called levitation is actually locking,

對，我們確實知道。

Yeah, we understand that.

不難想像，如果我用一個各面磁場都均一

You won't be surprised to hear that if I take this circular magnet,

的環狀磁鐵（來鎖定超導體），

in which the magnetic field is the same all around,

超導體會圍繞着這個磁鐵的中軸自由旋轉。

the superconductor will be able to freely rotate around the axis of the magnet.

為什麼？因為只要超導體保持旋轉， 就可以維持鎖定的狀態。

Why? Because as long as it rotates, the locking is maintained.

看到了嗎？我也可以調節，也可以轉超導體。

You see? I can adjust and I can rotate the superconductor.

這是沒有磨擦力的運動。仍然是懸浮， 但是（超導體）可以自由地移動。

We have frictionless motion. It is still levitating, but can move freely all around.

這就是量子鎖定，而我們可以讓超導體懸浮在磁鐵的上方。

So, we have quantum locking and we can levitate it on top of this magnet.

不過，這樣一個圓盤到底有多少磁通量子，多少磁場條呢？

But how many fluxons, how many magnetic strands are there in a single disk like this?

嗯，我們可以計算出來，結果是，非常多。

Well, we can calculate it, and it turns out, quite a lot.

在這個3英寸直徑的圓盤裡，有100億條磁場。

One hundred billion strands of magnetic field inside this three-inch disk.

這還不是最驚人的部分，因為最驚人的我還沒告訴你。

But that's not the amazing part yet, because there is something I haven't told you yet.

最驚人的是，這個你現在看到的超導體，

And, yeah, the amazing part is that this superconductor that you see here

只有一微米厚，非常地薄。

is only half a micron thick. It's extremely thin.

而這個超薄的超導體可以 懸浮起其自身重量70,000倍的物體。

And this extremely thin layer is able to levitate more than 70,000 times its own weight.

這是非常不尋常的事。它非常強壯。

It's a remarkable effect. It's very strong.

接下來，我把這個環形的磁鐵延伸，

Now, I can extend this circular magnet,

把它做成任何我想要的軌道。

and make whatever track I want.

比如說，我可以做一個像這樣的大圓環軌道。

For example, I can make a large circular rail here.

然後，當我把這個超導體圓盤放到軌道上方時，

And when I place the superconducting disk on top of this rail,

它會自由地（沿著軌道）移動。

it moves freely.

（掌聲）

(Applause)

而且，除此之外，我還可以調節它的位置，像這樣，然後旋轉，

And again, that's not all. I can adjust its position like this, and rotate,

它仍會在其新的位置上自由移動。

and it freely moves in this new position.

我甚至可以試試我還沒有試過的變化；

And I can even try a new thing; let's try it for the first time.

我可以把這個超導體放在這裡，

I can take this disk and put it here,

在它鎖定後--別動--

and while it stays here -- don't move --

我要試著把這個磁鐵軌道翻過來，

I will try to rotate the track,

希望，如果我沒錯的話，

and hopefully, if I did it correctly,

它會仍然懸浮。

it stays suspended.

（掌聲）

(Applause)

各位，這就是量子鎖定，不是懸浮。

You see, it's quantum locking, not levitation.

接下來，在它繼續轉的時候，

Now, while I'll let it circulate for a little more,

我要再告訴你一些關於超導體的其他事情。

let me tell you a little bit about superconductors.

現在--（笑聲）--

Now -- (Laughter) --

我們現在知道我們可以在超導體內傳導巨大的電流，

So we now know that we are able to transfer enormous amount of currents inside superconductors,

我們可以用超導體來產生強大的磁場，

so we can use them to produce strong magnetic fields,

如磁共振成像儀，粒子加速器等所需的巨大磁場。

such as needed in MRI machines, particle accelerators and so on.

我們也可以用超導體儲存能量，

But we can also store energy using superconductors,

因為沒有能量耗散。

because we have no dissipation.

我們也可以用超導體製造電纜，在電站間運送電流。

And we could also produce power cables, to transfer enormous amounts of current between power stations.

想像一下，你可以用一根超導電纜來給一整個電站供電。

Imagine you could back up a single power station with a single superconducting cable.

那麼，量子懸浮和量子鎖定的未來是什麼？

But what is the future of quantum levitation and quantum locking?

嗯，讓我舉個例子來回答這個簡單的問題。

Well, let me answer this simple question by giving you an example.

想像你有像我這樣的一個圓盤在手裡，

Imagine you would have a disk similar to the one I have here in my hand,

3英寸直徑，唯一不同的是，

three-inch diameter, with a single difference.

這個超導片不是一微米厚，

The superconducting layer, instead of being half a micron thin,

而是兩毫米厚，仍然很薄。

being two millimeters thin, quite thin.

這個兩毫米厚的超導片可以 在我手裡舉起1000公斤，一輛小車。

This two-millimeter-thin superconducting layer could hold 1,000 kilograms, a small car, in my hand.

很驚人吧。謝謝

Amazing. Thank you.

（掌聲）

(Applause)