Name: 為什麼光速其實慢得可怕？ (Why the Speed of Light is Actually Horribly Slow)
Uploaded: 2020-10-24T00:45:43.000Z
Duration: 8 min 7 s

基礎被動語態

this video was made possible by Brilliant.

這個視頻是由Brilliant公司製作的。

Start achieving your learning goals for 20% off by being one of the 1st 200 to sign up at brilliant dot org's slash real life.

作為前200名在Brilliant dot org's slash real life註冊的人之一，開始實現您的學習目標，享受20%的折扣。

情態副詞

Floor light is about the fastest thing that you can possibly imagine.

地板燈是你能想象到的最快的東西。

Think about how fast it seems when you turn on a light switch in your room and you see it instantly.

想一想，當你打開房間裡的電燈開關時，你會瞬間看到它的速度。

Philip with light or when you shine a flashlight on something in the light immediately appears on whatever you're shining it at.

菲利普用光或當你用手電筒照在某物上時，不管你照的是什麼，光都會立即出現。

因為我們的規模，感覺很即時。

Light moves so quickly that it might as well be.

光線移動的速度太快，以至於可能。

But when you move out beyond our scale, light gets slower and slower to the point where it quickly seems to more resemble a snail rather than, you know, light speed.

但當你移動到我們的尺度之外時，光會變得越來越慢，以至於它很快看起來更像一隻蝸牛，而不是，你知道，光速。

Light on Earth seems really, really fast because Earth is small.

地球上的光看起來真的非常快，因為地球很小。

Light travels at a speed of 299,792,458 m per second when in a vacuum, which is fast enough to completely orbit to the entire earth more than seven times in a single second, which looks like this while it's happening.

光在真空中時的速度為每秒299,792,458米，這速度足以在一秒鐘內完全繞到整個地球七次以上，這看起來就像這樣，而它正在發生。

When you flip on a light inside of your room, the light probably moves fast enough to reach across the entire room and just 1 500 1000th of a second, which to mere human eyes, basically feels instant.

當你在房間裡面打開一盞燈的時候，燈光的移動速度可能快到可以到達整個房間，而且只有1 500 1000分之一秒，在單純的人眼裡，基本上感覺就是瞬間。

This is why instant communication on the Internet between any two people on the Earth's surface is possible because Earth is a small enough place where lightspeed basically does mean the same thing as instant.

這也是為什麼地球表面任何兩個人之間都可以在互聯網上進行即時通訊的原因，因為地球是一個足夠小的地方，光速基本上確實和即時是一個意思。

But that all changes drastically when we zoom out just a little far away from the earth and get out into the rest of the universe.

但是，當我們把地球放大到離地球稍微遠一點的地方，到宇宙的其他地方去，這一切都發生了巨大的變化。

Far from being instantaneous, it takes light 1.255 seconds to cover the distance between Earth and the moon, which has all kinds of weird implications.

遠遠不是瞬時，光需要1.255秒才能覆蓋地球和月球之間的距離，這有各種奇怪的含義。

When the Apollo astronauts were there, there was a lag in communication between them and Mission Control back on Earth, because a message from Mission Control would take 1.255 seconds to arrive.

當阿波羅太空人在那裡的時候，他們和地球上的任務控制中心之間的通信有一個滯後，因為任務控制中心的資訊需要1.255秒才能到達。

And then the astronauts message would take 1.255 mawr seconds to come back for a total message, really time of 2.6 seconds round trip.

然後太空人的資訊需要1.255毫秒才能回來，總的資訊，真正的時間是來回2.6秒。

So in the future, when you're trying to communicate on Facebook or discord or whatever it is with someone living on the moon, you'll have to wait at least 2.6 seconds after sending a message to them before you actually get a response.

所以今後，當你想在Facebook或discord或其他什麼地方與生活在月球上的人交流時，你至少要在給他們發送消息後等待2.6秒才能真正得到迴應。

And it's all because of the limitations and speed of light speed communication.

而這一切都是因為光速通訊的限制和速度。

But communicating with somebody on the moon is still easy when compared with somewhere else, like, say, on Mars, which is a lot further away from us than the moon is in the future, when we have colonies with thousands or even millions of people living on Mars, the sheer distance away that Mars is is going to create lots of weird and interesting communication problems.

但是和月球上的人溝通還是很容易的，和其他地方相比，比如說，火星上，火星離我們的距離比月球要遠得多，未來當我們在火星上建立了殖民地，有幾千甚至幾百萬人生活在火星上，火星的距離之遠，會產生很多奇怪而有趣的溝通問題。

Since Earth and Mars have different orbits around the sun, Mars varies pretty drastically in her distance away from Earth.

由於地球和火星圍繞太陽的軌道不同，火星離地球的距離變化相當大。

On the close end, it takes light just over three minutes to cover the distance, which isn't bad.

在近處，光是走完這段距離就需要三分多鐘，還算不錯。

But on the far end, it'll take 22 minutes and 24 seconds, which makes instant communication impossible.

但在遠端，需要22分24秒，這就無法進行即時通訊。

If you have a friend who lives on Mars and you send them a message when Mars is furthest away from Earth.

如果你有一個住在火星上的朋友，當火星離地球最遠的時候，你給他們發個資訊。

Your message will take over 22 minutes just to get there, and then whenever they get around to responding to you, it'll take over 22 more minutes just to get back to you.

你的資訊光是到達那裡就需要22分鐘以上，然後每當他們要回復你的時候，就會多花22分鐘以上的時間來回復你。

Even if your friend on Mars response immediately when they get your message, it'll take about 45 minutes after you sent it before you get a response.

即使你在火星上的朋友收到你的資訊後立即迴應，也要在你發送後45分鐘左右才能得到迴應。

And that's the quickest response time possible.

So nobody should really get upset after not getting reply to for a while by a Martian.

所以，沒有人在被一個火星人暫時沒有得到回覆後，真的應該不會生氣。

This is going to become a big problem in the future, and I suspect it's going to cause human civilization on Mars to gradually feel mawr and mawr isolated and separated from Earth.

這在未來將成為一個大問題，我猜測這將導致火星上的人類文明逐漸感到毛毛雨，與地球隔絕。

The light just keeps getting slower and slower, the further we move away from Earth.

我們離地球越遠，光線就越慢，越慢。

The time it takes light to reach a Jupiter from Earth is anywhere between 33 to 53 minutes, meaning that when NASA has a probe in orbit, they have toe wait for around two hours, sometimes just a process information and send instructions to correct a potential navigation air, meaning that light speed instructions are sometimes too slow to arrive in time to fix the problem.

光線從地球到達木星所需的時間在33到53分鐘之間，這意味著當NASA的探測器在軌道上運行時，他們要趾高氣揚地等待兩個小時左右，有時僅僅是處理資訊和發送指令，以糾正潛在的導航空氣，這意味著光速指令有時會太慢，無法及時到達以解決問題。

Even light from the sun takes a while to reach us here on Earth, generally around eight minutes on average, which looks like this in real time.

即使是來自太陽的光，也需要一段時間才能到達我們地球上，一般平均8分鐘左右，它的實時情況是這樣的。

So slow, in fact, that if the sun all of a sudden just disappeared, for whatever reason, we wouldn't even realize it back here on Earth until eight minutes after it happened.

事實上，太慢了，如果太陽突然消失了，不管是什麼原因，我們甚至不會意識到它回到地球上，直到它發生後8分鐘。

And just forget about trying to maintain instant communication at the outer reaches of the solar system on Pluto's, because it takes light over five hours to get here from Earth.

就別想在冥王星的太陽系外圍保持即時通訊了，因為從地球到這裡需要5個多小時的光照。

And keep in mind everything that we've talked about so far is just within the confines of our own solar system.

請記住，到目前為止，我們所談的一切只是在我們自己的太陽系範圍內。

So light gets even slower when we get even further out the nearest other star to our sun.

所以當我們在離太陽最近的其他恆星更遠的地方，光線變得更慢。

Proxima Centauri is 4.24 light years away from the Earth, meaning it would take 4.24 years for light from Earth to reach it.

半人馬座Proxima Centauri距離地球4.24光年，這意味著來自地球的光需要4.24年才能到達它。

So just imagine what it would be like if we ever successfully managed to get colonists or a probe out on a planet.

所以試想一下，如果我們成功地把殖民者或探測器弄到一個星球上，那會是什麼樣子。

A single message between the colony and earth would take almost a decade to achieve because the lights being message would take 4.24 years each way, going back and forth to truly appreciate how insane that is.

殖民地和地球之間的一次資訊傳遞需要近十年的時間才能實現，因為燈光被資訊傳遞每一次都需要4.24年的時間，來來回回才能真正體會到這是多麼的瘋狂。

If there were a human colony on a planet there right now, they would only just now be hearing about news and memes from 2015.

如果現在那裡有一個星球上的人類殖民地，他們現在才會聽到2015年的新聞和備忘錄。

Do you even remember what was going on Back then?

Everybody's favorite educational YouTube channel hadn't even been created yet, and people were arguing over what color?

大家最喜歡的YouTube教育頻道還沒創建，大家就在爭論什麼顏色？

It just it's so this would be the current state of our planet that would be reaching the residents of Proxima Centauri B in the future.

它只是它所以這將是我們地球的現狀，未來將到達半人馬座B的居民。

It'll take 8.5 years just to get a response from somebody there after you send them a message.

你發完資訊後，光是得到那裡的人的回覆就需要8.5年。

If humanities life expectancy remains around 80 years in the future, you'll only be able to share a maximum of nine messages in your entire lifetime with somebody who lives around Proxima Centauri B.

如果未來人類的壽命仍然保持在80年左右，你一生最多隻能與生活在半人馬座B附近的人分享9條資訊。

And that's what the fastest form of light speed communication looks like with just the closest star to us in the universe, let alone the billions and trillions of stars and planets that exist even further away from that.

而這就是光速通訊的最快形式，只是與宇宙中離我們最近的恆星進行通訊的樣子，更不用說與之更遠的幾十億、上萬億的恆星和行星的存在了。

The speed of light is slower than you think it ISS, and it's too slow for our grander ambitions in space.

光速比你想象的要慢，國際空間站，對於我們在太空中的宏偉目標來說，它太慢了。

We just haven't really developed to the point yet where it's become a major problem for us, but it will happen eventually, and we need to be prepared for it the physics of light or complicated.

我們只是還沒有真正發展到它成為我們的主要問題的地步，但它最終會發生，我們需要為它做好準備光的物理學或複雜。

But even though light move slowly, there's all kinds of things that you can learn by looking at it.

但是，即使光移動得很慢，但通過觀察它，你可以學到各種東西。

You can use the principle of parallax toe, learn how far away a star is, or you can look at the stars luminosity to figure out how hot it ISS, and you can learn how to do both of these things and so much more right now in the astronomy course that's offered over at Brilliant, it's never too early or too late in life to learn something new, and what makes brilliant so special is that they help you learn the kinds of things that you were forced to and maybe struggled with when you were a kid.

你可以利用視差趾的原理，瞭解一顆恆星有多遠，或者你可以看恆星的光度來計算它的熱度，你可以學習如何做這兩件事，還有更多，現在在Brilliant提供的天文學課程中，學習新的東西永遠不會太早或太晚，是什麼讓Brilliant如此特別，他們幫助你學習那些你被迫學習的東西，也許在你還是個孩子的時候，你就會感到掙扎。

Physics, calculus, computer science, algebra and mawr.

物理、微積分、計算機科學、代數和數學。

But they actually make it fun and approachable.

但他們實際上是讓它變得有趣和平易近人。

The feeling of achievement when you finally understand something inconceivably complicated is amazing.

當你終於理解了一些難以想象的複雜事物時，那種成就感是很奇妙的。

And brilliance teaching style of breaking down big scary concepts into their smaller, more intuitive chunks makes that possible to experience for everyone.

而輝煌的教學風格，將大的可怕的概念分解成更小的、更直觀的塊狀，讓大家有可能體驗到。

You can even do this on the go with their app.

你甚至可以通過他們的應用程序在旅途中進行。

And if you're the type of person without a lot of free time but who still wants to learn new things, you can set a goal to do each of their daily challenges in those small, free moments that you get.

而如果你是那種沒有很多空閒時間，但仍然想學習新東西的人，你可以設定一個目標，在你得到的那些小而自由的時間裡，完成他們每天的每一個挑戰。

 Best of all, if you're one of the 1st 200 people to sign up by clicking the link in the description or by going to brilliant top org's slash real life floor, you'll even get 20% off. 

最重要的是，如果你是前200名通過點擊描述中的鏈接或到輝煌頂點org的斜槓真人樓報名的人，你甚至可以獲得20%的折扣。