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  • I want to ask you all to consider for a second

    譯者: Lauren Huang 審譯者: Diming Yu

  • the very simple fact

    請各位思考一下

  • that, by far,

    一個非常簡單的事實

  • most of what we know about the universe

    目前為止

  • comes to us from light.

    我們所知的宇宙

  • We can stand on the Earth and look up at the night sky

    都透過「光」而來

  • and see stars with our bare eyes.

    站在地球上仰望夜空

  • The Sun burns our peripheral vision.

    我們憑肉眼就能看得見星星

  • We see light reflected off the Moon.

    太陽照亮我們的視野邊界

  • And in the time since Galileo pointed that rudimentary telescope

    因為光的反射而看見月亮

  • at the celestial bodies,

    自從伽利略以最原始的望遠鏡

  • the known universe has come to us through light,

    舉目望天開始了觀測

  • across vast eras in cosmic history.

    一向以來,已知宇宙都是透過光來向我們傳達訊息

  • And with all of our modern telescopes,

    即便穿越了宇宙浩瀚的歷史

  • we've been able to collect

    以現代的望遠鏡

  • this stunning silent movie of the universe --

    我們能接收

  • these series of snapshots

    這齣令人驚異、讚歎的宇宙無聲電影

  • that go all the way back to the Big Bang.

    用許多連續圖形

  • And yet, the universe is not a silent movie

    一路回溯至大霹靂時期

  • because the universe isn't silent.

    但是,宇宙上演的並不是一齣默劇

  • I'd like to convince you

    因為宇宙其實並非一片死寂

  • that the universe has a soundtrack

    我想說服你們的就是這件事

  • and that soundtrack is played on space itself,

    宇宙是個有聲電影

  • because space can wobble like a drum.

    宇宙自己發出聲音成為它的聲部

  • It can ring out a kind of recording

    這是因為太空像鼓一樣會震動

  • throughout the universe

    它像唱片一樣可以發出聲音

  • of some of the most dramatic events as they unfold.

    傳遍整個宇宙

  • Now we'd like to be able to add

    尤其當某些極富戲劇效果的事件展開的時候

  • to a kind of glorious visual composition

    現在我們想嘗試

  • that we have of the universe --

    在炫麗奪目的視覺效果以外

  • a sonic composition.

    為我們的宇宙再加上

  • And while we've never heard the sounds from space,

    它聲音的部份

  • we really should, in the next few years,

    雖然我們從沒聽過來自太空的聲音

  • start to turn up the volume on what's going on out there.

    幾年之內,我們應該可以開始

  • So in this ambition

    把外面世界發出的聲音音量再調更大

  • to capture songs from the universe,

    在這雄心壯志

  • we turn our focus

    企圖接收宇宙譜出的歌曲驅動下

  • to black holes and the promise they have,

    帶領我們將目光轉向

  • because black holes can bang on space-time

    黑洞和它們的能量特性

  • like mallets on a drum

    因為黑洞能在空-時中發出聲響

  • and have a very characteristic song,

    像一根鼓棒一樣

  • which I'd like to play for you -- some of our predictions

    它的歌曲則極富特色

  • for what that song will be like.

    在此根據我們的假設

  • Now black holes are dark against a dark sky.

    將要播放一段黑洞可能會發出的聲音

  • We can't see them directly.

    黑洞是襯在黑底之上

  • They're not brought to us with light, at least not directly.

    不可能直接看得見

  • We can see them indirectly,

    它們不是直接以光的形式向我們呈現,至少沒有以直接的方式

  • because black holes wreak havoc on their environment.

    我們能以間接的方式看見它們

  • They destroy stars around them.

    也就是黑洞對它週遭環境施加的破壞

  • They churn up debris in their surroundings.

    諸如毀滅周圍恆星

  • But they won't come to us directly through light.

    將方圓以內碎片劇烈攪拌...等

  • We might one day see a shadow

    總之它們不會以可見光讓我們看見

  • a black hole can cast on a very bright background,

    有一天我們或許看得見它的影子

  • but we haven't yet.

    當黑洞遇上一個非常明亮的背景時這就有可能

  • And yet black holes may be heard

    但現在還在努力中

  • even if they're not seen,

    但黑洞是可以聽得見的

  • and that's because they bang on space-time like a drum.

    就算它們真的是我們所不能看見的

  • Now we owe the idea that space can ring like a drum

    能聽見黑洞是因它像鼓一樣,敲槌著空時

  • to Albert Einstein -- to whom we owe so much.

    我們會有這麼一個太空中響著鼓聲的念頭

  • Einstein realized that if space were empty,

    最該感謝的人是愛因斯坦,非常感謝

  • if the universe were empty,

    愛因斯坦明瞭如果太空是空的

  • it would be like this picture,

    宇宙是空的

  • except for maybe without the helpful grid drawn on it.

    就像這張照片

  • But if we were freely falling through the space,

    或者說實際上應沒有這些輔助線會像得更徹底些

  • even without this helpful grid,

    不過如果我們自由的墜入太空中

  • we might be able to paint it ourselves,

    就算沒有這些輔助線

  • because we would notice that we traveled along straight lines,

    我們自己也能畫的出這幅圖

  • undeflected straight paths

    因為我們會注意到自己是以直線運動前進

  • through the universe.

    以直線不偏轉的路徑

  • Einstein also realized --

    通過宇宙

  • and this is the real meat of the matter --

    愛因斯坦還想到另一件事

  • that if you put energy or mass in the universe,

    而那個部份才是更加精采

  • it would curve space,

    也就是,若將能量或質量放在宇宙中

  • and a freely falling object

    它會彎曲空間

  • would pass by, let's say, the Sun

    而自由落下的物體

  • and it would be deflected

    有可能會經過,譬如說,太陽

  • along the natural curves in the space.

    於是它的路徑會受偏轉

  • It was Einstein's great general theory of relativity.

    沿著空間自然曲線偏轉

  • Now even light will be bent by those paths.

    這是愛因斯坦的普通相對論

  • And you can be bent so much

    因為連光都會受這些路徑影響而彎曲

  • that you're caught in orbit around the Sun,

    彎曲到一個程度

  • as the Earth is, or the Moon around the Earth.

    你會被太陽抓住而繞著它依軌道運轉

  • These are the natural curves in space.

    就像地球繞太陽轉,月亮繞地球轉

  • What Einstein did not realize

    這就是空間的自然曲線

  • was that, if you took our Sun

    愛因斯坦沒想通的事情是

  • and you crushed it down to six kilometers --

    如果你拿著太陽

  • so you took a million times the mass of the Earth

    把它擠壓直到只剩6公里直徑大小

  • and you crushed it to six kilometers across,

    這是一團質量是地球100萬倍的東西

  • you would make a black hole,

    然後把它的體積壓縮到6公里寬

  • an object so dense

    這樣就是個黑洞

  • that if light veered too close, it would never escape --

    一個非常嚴密的物質

  • a dark shadow against the universe.

    如果靠得太近,連光不可能逃走

  • It wasn't Einstein who realized this,

    成為一個相對於宇宙的黑色陰影

  • it was Karl Schwarzschild

    愛因斯坦沒領悟到這件事情

  • who was a German Jew in World War I --

    這是卡爾史瓦西解出來的

  • joined the German army already an accomplished scientist,

    他是德國猶太人,在第一次世界大戰時

  • working on the Russian front.

    在入伍時已是一位傑出科學家

  • I like to imagine Schwarzschild in the war in the trenches

    在德俄邊境前線工作

  • calculating ballistic trajectories for cannon fire,

    我總愛想像史瓦西是躲在戰爭時期的壕溝裡頭

  • and then, in between,

    邊計算高射炮的發射彈道

  • calculating Einstein's equations --

    邊偶爾計算一下

  • as you do in the trenches.

    愛因斯坦的公式

  • And he was reading Einstein's recently published

    壕溝裡能做的事情不多

  • general theory of relativity,

    他正拜讀愛因斯坦最新的

  • and he was thrilled by this theory.

    普通相對論

  • And he quickly surmised

    令他大感驚訝的理論

  • an exact mathematical solution

    他很快推算出

  • that described something very extraordinary:

    一道精確的數學解答

  • curves so strong

    極不尋常的描述了一個現象

  • that space would rain down into them,

    一道強大的曲線

  • space itself would curve like a waterfall

    空間會順勢下流

  • flowing down the throat of a hole.

    空間本身會像瀑布一般的彎曲

  • And even light could not escape this current.

    向下流入一個喉嚨敞開的洞

  • Light would be dragged down the hole

    即便是光也無法逃離這股流勢

  • as everything else would be,

    光會被拉入這個洞中

  • and all that would be left would be a shadow.

    和其他任何東西一樣

  • Now he wrote to Einstein,

    所有東西最後都會只剩下一個影子

  • and he said, "As you will see,

    史瓦西寫信告訴愛因斯坦

  • the war has been kind to me enough.

    他說,「且看,

  • Despite the heavy gunfire,

    戰爭對我是多麼慷慨有餘啊,

  • I've been able to get away from it all

    即便在戰火交織下

  • and walk through the land of your ideas."

    我也能有遠離這一切的一個某處可去

  • And Einstein was very impressed with his exact solution,

    一步步前進在由你的理論所佔領的土地上。」

  • and I should hope also the dedication of the scientist.

    愛因斯坦對史瓦西精確的解答實在印象深刻

  • This is the hardworking scientist under harsh conditions.

    我應該期望自己有科學家這樣全心全力

  • And he took Schwarzschild's idea

    在這樣艱困的處境下仍辛勤工作

  • to the Prussian Academy of Sciences the next week.

    帶著著史瓦西的理論想法

  • But Einstein always thought black holes were a mathematical oddity.

    一週後,愛因斯坦前往波斯科學院

  • He did not believe they existed in nature.

    愛因斯坦一向以為黑洞只不過是個純數學的怪物

  • He thought nature would protect us from their formation.

    他並不相信自然界真有這個東西存在

  • It was decades

    他認為自然界應該會在創生的過程中保護我們

  • before the term "black hole" was coined

    幾十年過去

  • and people realized

    黑洞一詞被憑空創造問世

  • that black holes are real astrophysical objects --

    人們理解到

  • in fact they're the death state

    黑洞是天文物理中真實的天體

  • of very massive stars

    事實上它們是一種最終的境界

  • that collapse catastrophically

    大質量恆星們的最終結局

  • at the end of their lifetime.

    災難性的崩塌瓦解

  • Now our Sun will not collapse to a black hole.

    當它的生命走到盡頭時

  • It's actually not massive enough.

    我們的太陽不會塌縮成黑洞

  • But if we did a little thought experiment --

    事實上它的質量還不夠形成為黑洞

  • as Einstein was very fond of doing --

    但如果我們運用思考來做個實驗

  • we could imagine

    就像愛因斯坦很喜歡做的事情一樣

  • putting the Sun crushed down to six kilometers,

    我們不妨想像

  • and putting a tiny little Earth around it in orbit,

    把太陽壓縮成6公里大小

  • maybe 30 kilometers

    把一個超微小地球放在它旁邊依軌道運行

  • outside of the black-hole sun.

    距離約30公里

  • And it would be self-illuminated,

    在這顆太陽黑洞外面30公里處

  • because now the Sun's gone, we have no other source of light --

    然後地球自己會發光

  • so let's make our little Earth self-illuminated.

    因為沒有太陽了,我們也將失去光源--

  • And you would realize you could put the Earth in a happy orbit

    只好先假設地球變成是發光體的情形

  • even 30 km

    你會發現這個距離之下地球軌道

  • outside of this crushed black hole.

    在距離黑洞

  • This crushed black hole

    30公里以外

  • actually would fit inside Manhattan, more or less.

    一個被壓縮的黑洞

  • It might spill off into the Hudson a little bit

    事實上就和紐約市中心的曼哈頓區差不多大而已

  • before it destroyed the Earth.

    有時它或許會碰到一點哈得遜區

  • But basically that's what we're talking about.

    在它快要吞滅地球之前

  • We're talking about an object that you could crush down

    基本上我們說的就是體積這麼小的一個東西

  • to half the square area of Manhattan.

    我們說的這個東西是你可以把它壓縮到

  • So we move this Earth very close --

    只有曼哈頓方圓一半大的區域

  • 30 kilometers outside --

    我們把這個地球移動到非常靠近 --

  • and we notice it's perfectly fine orbiting around the black hole.

    30公里外的這個距離

  • There's a sort of myth

    這是繞行這顆黑洞完美的軌道

  • that black holes devour everything in the universe,

    這有點神秘

  • but you actually have to get very close to fall in.

    黑洞無一例外的吞滅宇宙裡的一切物體

  • But what's very impressive is that, from our vantage point,

    但事實上你必須非常靠近它才能掉的下去

  • we can always see the Earth.

    但令人驚訝的是,從我們的觀望點

  • It cannot hide behind the black hole.

    我們總是看得到地球

  • The light from the Earth, some of it falls in,

    它沒辦法躲藏在黑洞的後方

  • but some of it gets lensed around and brought back to us.

    這時有些從地球發出的光會掉入黑洞中

  • So you can't hide anything behind a black hole.

    有些會因受到透鏡得作用,傳回來讓我們看見

  • If this were Battlestar Galactica

    你沒辦法把一樣東西藏在黑洞後面

  • and you're fighting the Cylons,

    如果是在科幻影集「太空堡壘」中

  • don't hide behind the black hole.

    你和塞隆人正在作戰

  • They can see you.

    千萬別選在一個黑洞的後面跟他玩躲迷藏

  • Now, our Sun will not collapse to a black hole --

    敵人一定會看見你

  • it's not massive enough --

    太陽不會塌縮成黑洞

  • but there are tens of thousands of black holes in our galaxy.

    它質量不夠

  • And if one were to eclipse the Milky Way,

    我們的銀河系裡有上萬顆黑洞

  • this is what it would look like.

    如果銀河系裡發生了「食」的現象

  • We would see a shadow of that black hole

    看起來會像這樣

  • against the hundred billion stars

    我們會看到一個黑洞的影子

  • in the Milky Way Galaxy and its luminous dust lanes.

    在數千億顆明亮恆星的映襯之下

  • And if we were to fall towards this black hole,

    在銀河系還有許多明亮的塵埃帶中

  • we would see all of that light lensed around it,

    若我們朝黑洞裡頭掉進去

  • and we could even start to cross into that shadow

    我們會看見受到透鏡作用的光環繞在外層

  • and really not notice that anything dramatic had happened.

    我們甚至開始穿透那個陰影

  • It would be bad if we tried to fire our rockets and get out of there

    卻並不會真的發現什麼太有戲劇效果的事情

  • because we couldn't,

    試圖從黑洞裡發射一顆火箭逃出來並不是個太好的主意

  • anymore than light can escape.

    因為根本不可行

  • But even though the black hole is dark from the outside,

    連光都逃不掉

  • it's not dark on the inside,

    不過雖然黑洞從外面看是漆黑一片

  • because all of the light from the galaxy can fall in behind us.

    內層卻不是黑的

  • And even though, due to a relativistic effect known as time dilation,

    因為所有銀河系而來的光都在我們身後掉進來

  • our clocks would seem to slow down

    儘管如此,由於時間膨脹的相對關係

  • relative to galactic time,

    我們的時鐘會慢下來

  • it would look as though the evolution of the galaxy

    相對於星系時間

  • had been sped up and shot at us,

    看起來會好像是銀河系的演化

  • right before we were crushed to death by the black hole.

    加速度進行並且正對著我們而來

  • It would be like a near-death experience

    然後我們將被黑洞壓碎而死掉

  • where you see the light at the end of the tunnel,

    很像是個瀕死經驗

  • but it's a total death experience.

    看得見光在隧道末端...

  • (Laughter)

    但這經驗其實會讓你非死不可

  • And there's no way of telling anybody

    (笑聲)

  • about the light at the end of the tunnel.

    你也沒辦法跟任何人說這個經歷

  • Now we've never seen a shadow like this of a black hole,

    說你看得見光在隧道末端...

  • but black holes can be heard,

    我們從來沒看見過像這樣的一個黑洞的影子

  • even if they're not seen.

    但是我們聽得見黑洞

  • Imagine now taking an astrophysically realistic situation --

    雖然就算看不到

  • imagine two black holes that have lived a long life together.

    想像現在天文物理中有這樣一個現實情境

  • Maybe they started as stars

    有兩個黑洞在一起,已經過了很久的時間

  • and collapsed to two black holes --

    也許從它們是恆星的身分開始

  • each one 10 times the mass of the Sun.

    然後崩塌為兩個黑洞

  • So now we're going to crush them down to 60 kilometers across.

    每一個都有太陽質量的十倍大

  • They can be spinning

    所以現在我們把它們壓縮為60公里大小

  • hundreds of times a second.

    它們可能在自轉

  • At the end of their lives,

    以每秒數百次的速度自轉

  • they're going around each other very near the speed of light.

    當它們的恆星生命走到盡頭時

  • So they're crossing thousands of kilometers

    它們以幾乎是光速互繞對方轉

  • in a fraction of a second,

    以每秒數千里的速度

  • and as they do so, they not only curve space,

    快速移動

  • but they leave behind in their wake

    如此,不只扭曲了空間

  • a ringing of space,

    它們也在所經之處的後方

  • an actual wave on space-time.

    留下一個發出響聲的空間

  • Space squeezes and stretches

    在空時中有一道實際的波

  • as it emanates out from these black holes

    太空壓縮也延伸

  • banging on the universe.

    這些自黑洞中發出來的波

  • And they travel out into the cosmos

    敲擊著宇宙

  • at the speed of light.

    它們朝向宇宙

  • This computer simulation

    以光速奔去

  • is due to a relativity group at NASA Goddard.

    這個電腦模擬結果

  • It took almost 30 years for anyone in the world to crack this problem.

    是由美國航太總署戈達德太空中心的相對論組製作

  • This was one of the groups.

    地球上很多人近30年時間都用來解答出這一道題目

  • It shows two black holes in orbit around each other,

    戈達德小組是其中之一

  • again, with these helpfully painted curves.

    它顯示的情況是兩個黑洞彼此互繞

  • And if you can see -- it's kind of faint --

    如前述,藉由自然界事先就畫好的曲線

  • but if you can see the red waves emanating out,

    它們看起來有點暗淡

  • those are the gravitational waves.

    但你看得見紅色的波向外散射

  • They're literally the sounds of space ringing,

    這就是重力波

  • and they will travel out from these black holes at the speed of light

    使太空發出聲響

  • as they ring down and coalesce

    它們從黑洞裡以光速跑出來

  • to one spinning, quiet black hole

    震盪並聯合

  • at the end of the day.

    合成為一個波,安靜的黑洞

  • If you were standing near enough,

    在喧囂後重歸寧靜

  • your ear would resonate

    倘若你站的距離夠近

  • with the squeezing and stretching of space.

    耳中會回響著

  • You would literally hear the sound.

    空間擠壓和伸展的聲音

  • Now of course, your head would be squeezed and stretched unhelpfully,

    你會真的聽得見聲音

  • so you might have trouble understanding what's going on.

    當然你的頭也會被壓縮拉長,這是無可避免的

  • But I'd like to play for you

    所以其實你也根本搞不清楚現在是什麼情況

  • the sound that we predict.

    不過我想播一段這個給你聽

  • This is from my group --

    這是我們預測中的聲音

  • a slightly less glamorous computer modeling.

    從我的團隊而來的數據