Back in the day, sailors used to tell stories about these monster waves.

過去，水手們經常講述這些怪浪的故事。

These waves were enormous, two to three times taller than the tallest average waves, even in stormy conditions, and big enough to sink ships as big as ocean liners and oil platforms.

這些海浪非常巨大，即使在暴風雨的情況下，也比最高的平均海浪高出兩到三倍，足以擊沉像海輪和石油平臺這樣大的船隻。

They would talk about being battered by this giant wave and barely living to tell the tale.

他們會談論自己被巨浪擊倒後勉強活下來的故事。

And these waves would form in the open ocean, randomly, spontaneously, and without an obvious cause.

而這些波浪會在大洋中隨機、自發地形成，沒有明顯的原因。

But people tend to exaggerate.

但人們往往會誇大其詞。

And scientists who study the ocean didn't buy it.

而研究海洋的科學家們並不買賬。

These tales of so-called rogue waves were happening far too frequently to be true.

這些所謂 "惡浪 "的傳說發生得太頻繁了，根本不可能是真的。

And according to their calculations, rogue waves could form based on a wave phenomenon known as superposition.

根據他們的計算，流氓波可能是根據一種被稱為疊加的波現象形成的。

When two waves combine crest to crest, the waves double in size.

當兩個波峰結合在一起時，波浪的大小會翻倍。

And when they combine trough to crest, they cancel out.

而當它們從波谷結合到波峰時，就會相互抵消。

So if a bunch of normal waves happen to meet at the right place at the right time, they could create one monster wave.

是以，如果一群正常的波浪碰巧在正確的時間、正確的地點相遇，就會形成一個巨浪。

This wave would break with a force of 100 metric tons per square meter.

這一海浪的衝擊力為每平方米 100 公噸。

That's like 15 elephants standing on your car.

這就像 15 頭大象站在你的車上。

Needless to say, your little boat would not fare well.

不用說，你的小船也不會好過。

But according to superposition, these waves should be incredibly rare.

但根據疊加原理，這些波應該非常罕見。

They should happen maybe once every few years.

這種情況可能每隔幾年就會發生一次。

And it took scientists until 1995, barely 20 years ago, to realize they were wrong.

直到 1995 年，也就是不到 20 年前，科學家們才意識到他們錯了。

On New Year's Day in 1995, a 25 and 1 half meter wave crashed against an oil platform off the coast of Norway.

1995 年元旦，一個 25.5 米高的巨浪衝向挪威海岸的一個石油平臺。

This wave was twice as high as any wave ever measured in that part of the ocean.

這個海浪比在該海域測量到的任何海浪都要高出一倍。

And it wasn't a tsunami or a tidal bore, which is caused when ocean tides meet river currents.

這不是海嘯，也不是潮汐孔，潮汐孔是海洋潮汐與河流水流交匯時產生的。

So for the first time, a rogue wave was measured.

是以，第一次測量到了流氓波。

And scientists could no longer deny their existence.

科學家們再也無法否認它們的存在。

So they looked further.

於是，他們進一步尋找。

A study by the European Space Agency in 2001 using satellite data found more than 10 high amplitude rogue waves occurring within a three week period.

歐洲航天局 2001 年利用衛星數據進行的一項研究發現，在三週內發生了 10 多次高振幅流氓波。

So maybe all those ships of yore that disappeared into thin air were actually sunk by monster waves, because rogue waves aren't so rare after all.

所以，也許昔日那些憑空消失的船隻其實都是被怪浪擊沉的，因為怪浪畢竟不是那麼罕見。

Why were scientists so wrong?

科學家們為什麼錯得那麼離譜？

Well, it turns out ocean waves are really complicated, more complicated than just superposition.

原來，海浪真的很複雜，比疊加更復雜。

Imagine trying to explain a human to an alien.

試想一下，如何向外星人解釋人類？

You might start with a stick figure, which is pretty good.

你可以從一個棒圖開始，這很不錯。

You've got the head, torso, and some limbs.

你有頭、軀幹和一些四肢。

But then try explaining the circulatory system.

但你可以試著解釋一下循環系統。

Yeah.

是啊

In the same way, superposition can describe some aspects of ocean waves.

同樣，疊加也可以描述海浪的某些方面。

But it's just too simple to explain most phenomena like rogue waves.

但是，這太簡單了，無法解釋流氓波等大多數現象。

So what's missing?

還缺什麼？

Well, waves form due to many, many factors.

波的形成有很多很多因素。

Wind, tides, the geology of the ocean floor, differences in temperature throughout the ocean, even varying amounts of salt can affect ocean waves.

風、潮汐、海底地質、整個海洋的溫差，甚至不同數量的鹽分都會影響海浪。

And you end up with this complicated, unexpected, chaotic system of wave behavior.

最後你就會看到這個複雜的、意想不到的、混亂的波浪行為系統。

You can see interdependent behavior like this in something as simple as a double pendulum.

你可以在雙擺這樣簡單的東西上看到這種相互依存的行為。

Initially, it behaves pretty normally.

最初，它的表現非常正常。

But the pendulum's behavior soon becomes utterly unpredictable, because the motion of the bottom joint depends on the motion of the top joint.

但擺的行為很快就變得完全不可預測，因為底部關節的運動取決於頂部關節的運動。

So it turns to chaos.

於是就變成了混亂。

Physicists call these weird behaviors nonlinear effects.

物理學家把這些奇怪的行為稱為非線性效應。

Many of the processes that we're familiar with are linear processes.

我們熟悉的許多流程都是線性流程。

Baking cookies, for the most part, is linear.

烤餅乾在大多數情況下是直線型的。

If you double your ingredients, you make twice as many cookies.

如果配料加倍，餅乾的數量也會加倍。

Similarly, when you use superposition to add two waves of the same size, the height doubles.

同樣，當您使用疊加法將兩個相同大小的波相加時，高度也會增加一倍。

On the other hand, watering a cactus twice as much doesn't necessarily mean it will grow twice as high.

另一方面，給仙人掌澆兩倍的水並不一定意味著它會長高一倍。

In fact, it might even die.

事實上，它甚至可能死去。

This is a nonlinear process.

這是一個非線性過程。

It means that increasing your input doesn't necessarily increase your output, well, linearly.

這意味著，增加輸入並不一定會線性增加輸出。

Some phenomena seem linear at first, but in fact become nonlinear, like stretching a rubber band.

有些現象起初看起來是線性的，但實際上卻變成了非線性的，就像拉伸橡皮筋一樣。

If you pull twice as hard, it will stretch twice as long.

如果你用兩倍的力氣拉，它就會拉長兩倍。

But if you stretch it four, six, eight times as hard, it won't keep stretching proportionally.

但如果你用四倍、六倍、八倍的力量拉伸它，它就不會一直按比例拉伸。

It'll snap.

會斷掉的

Despite the fact that the most common model of adding waves, superposition, is linear, ocean waves are nonlinear.

儘管最常見的海浪疊加模型是線性的，但海浪卻是非線性的。

Physicists and mathematicians figured out that only by adding in these nonlinear effects could they figure out why rogue waves are so common.

物理學家和數學家發現，只有加入這些非線性效應，才能弄清流氓波如此常見的原因。

It turns out that when you add two ocean waves, you don't necessarily double the height.

事實證明，當你增加兩個海浪時，不一定會使高度增加一倍。

Waves are chaotic and hard to predict.

波浪是混亂的，難以預測。

Depending on the scenario, you could have a bunch of normal waves passing by, and then through nonlinear processes, energy is passed between waves, concentrated on one wave that becomes a giant monster rogue wave.

根據不同的情況，可能會有一些正常的波浪經過，然後通過非線性過程，能量在波浪之間傳遞，集中在一個波浪上，成為一個巨大的怪獸流氓波。

That's just scary.

這太可怕了。

So now that we know about nonlinear chaotic effects, does that mean that our superposition model is no good?

那麼，既然我們已經知道了非線性混沌效應，這是否意味著我們的疊加模型就不行了呢？

Well, no.

嗯，沒有。

In certain circumstances, like calm water with small waves, you can use superposition to add and cancel out waves.

在某些情況下，比如波浪較小的平靜水面，可以使用疊加法來增加或抵消波浪。

Just like with our rubber band, it started out linear when you first start stretching it.

就像我們的橡皮筋一樣，剛開始拉伸時是線性的。

It's only when you take it to the extreme that it becomes nonlinear.

只有當你把它發揮到極致時，它才會變得非線性。

Just like Newton's laws of motion are great until you move near the speed of light.

就像牛頓的運動定律在接近光速之前都是偉大的一樣。

Then you need Einstein's relativity.

那你就需要愛因斯坦的相對論。

This is an excellent reminder that science is based on models and not absolute truths.

這很好地提醒我們，科學是建立在模型之上的，而不是絕對真理。

Scientists were wrong when they thought that they knew the entire picture about ocean waves.

當科學家們認為他們瞭解海浪的全貌時，他們就錯了。

But it's exciting when scientists are wrong.

但當科學家們出錯時，還是很令人興奮的。

It just means that there are so many more details hidden in nature that we have yet to discover.

這隻能說明，大自然中還隱藏著許多我們尚未發現的細節。

Thank you so much for watching, and happy physicsing.

感謝您的收看，祝您物理學習愉快。

This episode of Physics Girl is supported by audible.com.

本集《物理女孩》由 audible.com 提供支持。

Right now, Audible is offering viewers a 30-day trial period.

目前，Audible 正在為觀眾提供 30 天的試用期。

Check out audible.com slash physics girl to access their audio programs and titles.

請訪問 audible.com slash physics girl，訪問他們的音頻節目和標題。

Reading is good for you.

閱讀對你有好處

I recently reread Ender's Game by Orson Scott Card.

我最近重讀了奧森-斯科特-卡德的《安德的遊戲》。

Go to audible.com slash physics girl, and make sure to use that link to help us out and to get a membership trial.

請訪問 audible.com slash physics girl，確保使用該鏈接來幫助我們，並獲得會員試用資格。

♪♪♪ ♪♪

♪♪♪ ♪♪