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  • From far away, stars are tiny points of light. But up close, stars are massive, seething,

    從遠處看,恆星是微弱的光點。 但近距離,恆星是巨大的,沸騰的,

  • fiery balls of burning gas. This fierce display does not last forever. Eventually, the nuclear

    燃燒氣體的火熱球。這種激烈的展示 不會永遠持續下去。最終,核

  • fusion which powers the star will burn all its fuel. Gravity then collapses the remaining

    為星星供電的融合將燃燒所有 它的燃料。重力然後折疊剩餘的

  • matter together. For very large stars, what happens next is a display of extremes. First,

    在一起。對於非常大的星星,什麼 接下來發生的是極端的顯示。第一,

  • the star explodes in a supernova, scattering much of its matter throughout the universe.

    這顆恆星在超新星中爆炸,散射 整個宇宙中的大部分問題。

  • For a brief moment, the dying star outshines its entire galaxy. But once the light fades

    短暫的一瞬間,這位瀕臨死亡的明星將會熠熠生輝 它的整個星系。但是一旦光線消失

  • and darkness returns, the remaining matter forms an object so dense that anything that

    和黑暗回歸,剩下的事情 形成一個如此密集的物體

  • gets too close will completely disappear from view. THIS is a black hole

    太靠近會完全消失 視圖。這是一個黑洞......

  • The idea of a black hole originated hundreds of years ago. In 1687, Isaac Newton published

    黑洞的想法起源於數百人 多年前1687年,艾薩克·牛頓出版

  • his landmark work known as The Principia. Here he detailed his laws of motion and the

    他的標誌性作品稱為The Principia。 在這裡,他詳細闡述了他的運動定律和

  • universal law of gravitation. Using a thought experiment involving a cannon placed on a

    普遍萬有引力定律。用一個想法 實驗涉及放置在大砲上的大砲

  • very tall mountain, Newton derived the notion of escape velocity. This is the launch speed

    非常高的山,牛頓得出了這個概念 逃逸速度這是發射速度

  • required to break free from the pull of gravity. In 1783, the English clergyman John Michell

    需要擺脫重力的拉力。 1783年,英國牧師約翰·米歇爾

  • found that a star 500 times larger than our sun would have an escape velocity greater

    發現一顆恆星比我們大500倍 太陽的逃逸速度會更大

  • than the speed of light. He called these giant objectsdark starsbecause they could

    比光的速度。他稱這些巨人 對象“黑暗的星星”,因為他們可以

  • not emit starlight. This idea lay dormant for more than a century.

    不發出星光。這個想法處於休眠狀態 一個多世紀以來。

  • Then, in the early 20th century, Albert Einstein developed two theories of relativity that

    然後,在20世紀初,阿爾伯特愛因斯坦 發展了兩種相對論

  • changed our view of space and time: the special theory and the general theory. The special

    改變了我們對空間和時間的看法:特殊的 理論和一般理論。特別的

  • theory is famous for the equation E=mc2. The general theory painted a new and different

    理論以等式E = mc2而聞名。該 一般理論描繪了一個新的和不同的

  • picture of gravity. According to the general theory of relativity, matter and energy bend

    引力圖。據將軍說 相對論,物質和能量彎曲

  • space and time. Because of this, objects which travel near a large mass will appear to move

    空間和時間。正因為如此,對象當中 大質量附近的旅行似乎會移動

  • along a curved path because of the bending in spacetime. We call this effect gravity.

    由於彎曲,沿著彎曲的路徑 在時空。我們稱這種效應為引力。

  • One consequence of this idea is that light is also affected by gravity. After all, if

    這個想法的一個結果是光 也受到重力的影響。畢竟,如果

  • spacetime is curved, then everything must follow along a curved path, including light.

    時空是彎曲的,然後一切都必須 沿著彎曲的路徑行進,包括光線。

  • Einstein published his general theory of relativity in 1915. And while Newton's theory of gravity

    愛因斯坦發表了他的廣義相對論 在1915年。而牛頓的引力理論

  • could be expressed using a simple formula, Einstein's theory required a set of complex

    可以用一個簡單的公式來表達, 愛因斯坦的理論需要一套複雜的理論

  • equations known as thefield equations.” Only a few months after Einstein's publication,

    被稱為“場方程”的方程式。 愛因斯坦出版後僅幾個月,

  • the German scientist Karl Schwarzschild found a surprising solution. According to the field

    德國科學家Karl Schwarzschild發現 一個令人驚訝的解決方根據該領域

  • equations, an extremely dense ball of matter creates a spherical region in space where

    方程式,一個非常密集的物質球 在空間中創建一個球形區域

  • nothing can escape, not even light. A curious result, but did such things actually exist?

    沒有什麼可以逃脫,甚至沒有光。好奇 結果,但這樣的事情確實存在嗎?

  • At first, the idea of a black sphere in space from which nothing could escape was considered

    首先,在空間中的黑色球體的想法 考慮到沒有任何東西可以逃脫

  • purely a mathematical result, but one which would not really happen. However, as the decades

    純粹是一個數學結果,但其中一個 不會真的發生。然而,就像幾十年

  • passed, our understanding of the lifecycle of stars grew. It was observed that some dying

    通過了,我們對生命週期的理解 星星長大了。有人觀察到有些人死亡

  • stars became pulsars, another exotic object predicted by theory. This suggested that dark

    恆星變成了脈衝星,另一個奇異物體 理論預測。這表明黑暗

  • stars could actually be real as well. These strange spheres were namedblack holes,”

    明星實際上也可能是真實的。這些 奇怪的球體被稱為“黑洞”

  • and scientists began the hard work of finding them, describing them and understanding

    科學家們開始努力尋找 他們,描述他們和理解

  • how they are created.

    它們是如何創建的。

  • But how do you find an object in space that is completely black? Luckily, because black

    但是你如何在太空中找到一個物體呢? 完全黑了?幸運的是,因為黑色

  • holes have a large mass, they also have a large gravitational field. So while we may

    孔的質量很大,它們也有一個 大引力場。所以儘管我們可能

  • not be able to SEE a black hole, we can observe its gravity pulling on its neighbors. With

    我們無法觀察到黑洞 它的引力拉近了它的鄰居。同

  • this in mind, astronomers looked for a place where a visible star and a black hole were

    考慮到這一點,天文學家尋找一個地方 那裡有一顆可見的恆星和一個黑洞

  • in close proximity to one another. One such place is binary stars.

    在彼此附近。一個這樣的 地方是二元星。

  • A binary star is a system of two stars orbiting one another. We can spot them in several ways.

    雙星是由兩顆恆星軌道運行的系統 另一個。我們可以通過幾種方式發現它們。

  • You can look for stars that change position back and forth ever-so-slightly. Alternatively,

    你可以尋找改變位置的星星 來回如此輕微。或者,

  • if you observe a binary star from the side, the brightness will change when one star passes

    如果你從側面觀察到一個雙星, 當一顆星通過時亮度會改變

  • behind the other. So it's possible that somewhere in space, there's a binary star

    在另一個之後。所以有可能 在太空的某個地方,有一個雙星

  • consisting of a black hole and a visible star. In fact, such binary systems have been observed!

    由黑洞和可見星組成。 事實上,已經觀察到了這樣的二元系統!

  • Astronomers have found stars orbiting an invisible companion. From the size of the visible star

    天文學家發現恆星繞著無形的軌道運行 伴侶。從可見星的大小

  • and its orbit, astronomers calculated the mass of its invisible neighbor. It fit the

    天文學家計算了它的軌道 它看不見的鄰居的質量。它適合

  • profile of a black hole.

    黑洞的輪廓。

  • Since we can't see a black hole, is there a way to find its size? From Einstein's

    既然我們看不到黑洞,那就是 有辦法找到它的大小?來自愛因斯坦

  • field equations, we know that given the mass of a black hole, we can determine the size

    場方程,我們知道給定質量 一個黑洞,我們可以確定大小

  • of the sphere that separates the region of no escape from the rest of space. The radius

    分離區域的球體 沒有逃離其餘的空間。半徑

  • of this sphere is called the Schwarzschild radius in honor of Karl Schwarzschild. The

    這個領域被稱為Schwarzschild 為紀念Karl Schwarzschild而設的半徑。該

  • surface of the sphere is called the event horizon. If anything crosses the event horizon,

    球體的表面稱為事件 地平線。如果有什麼東西穿過事件視界,

  • it's gone foreverhidden from the rest of the universe.

    它永遠消失了 - 隱藏在其他地方 宇宙

  • This means, once you know the MASS of a black hole, you can compute its SIZE using a simple

    這意味著,一旦你知道了黑色的MASS 孔,你可以用簡單的方法計算它的SIZE

  • formula. And it's actually quite easy to measure the mass of a black hole. Just take

    式。它實際上很容易 測量黑洞的質量。拿走吧

  • a standard issue space probe and shoot it into orbit around the black hole. Just like

    一個標準的問題空間探測器並拍攝它 進入黑洞周圍的軌道。就像

  • any other system of orbiting bodieslike the Earth orbiting the Sun, or the Moon orbiting

    任何其他軌道運動系統 - 如 地球繞太陽運行,或繞月球軌道運行

  • the Earththe size and period of the orbit will tell you the mass of the black hole.

    地球 - 軌道的大小和周期 會告訴你黑洞的質量。

  • If you don't have a space probe handy, then compute the mass and orbit of a companion

    如果你沒有方便的太空探測器,那麼 計算伴侶的質量和軌道

  • star and use that to find the Schwarzschild radius.

    明星並用它來尋找Schwarzschild 半徑。

  • Black holes come in many sizes. If it was made from a dying star, then we call it a

    黑洞有多種尺寸。如果它是 由垂死的恆星製成,然後我們稱之為

  • stellar massblack hole, because its mass is in the same range as stars. But we

    “恆星質量”黑洞,因為它 質量與恆星的範圍相同。但我們

  • can go bigger - much bigger. And to do so, we are going to visit the center of a galaxy.

    可以變得更大 - 更大。要這樣做, 我們要去參觀銀河系的中心。

  • Galaxies can contain billions and billions of stars, all orbiting a central point. Scientists

    星係可以包含數十億甚至數十億 所有的恆星,都圍繞著一個中心點。科學家們

  • now believe that in the center of most galaxies lives a black hole which we call a “supermassive

    現在相信在大多數星系的中心 生活在一個我們稱之為“超大質量”的黑洞

  • black hole,” because of its tremendous mass. The size can vary from hundreds of thousands

    黑洞,“因為它的巨大質量。 大小可以從幾十萬不等

  • to even billions of solar masses. For example, at the center of our own Milky Way galaxy

    甚至數十億太陽質量。例如, 在我們銀河系的中心

  • is a supermassive black hole with a mass 4 million times that of our sun.

    是一個質量為4的超大質量黑洞 我們太陽的百萬倍。

  • Black holes have another property we can measure - their spin. Just like the planets, stars

    黑洞還有另一種我們可以測量的屬性 - 他們的旋轉。就像行星,恆星一樣

  • rotate. And different stars spin at different speeds. Imagine we can adjust the size of

    旋轉。不同的星星旋轉不同 速度。想像一下,我們可以調整大小

  • this star but keep the mass constant. If we increase the radius, the spinning slows down

    這顆恆星但保持質量不變。要是我們 增加半徑,旋轉速度減慢......

  • If we decrease the size, the spinning speeds up. But while the rotational speed can vary,

    如果我們減小尺寸,旋轉速度 起來。但是雖然轉速可以變化,

  • the angular momentum never changes - it remains constant. Even if the star were to collapse

    角動量永遠不會改變 - 它仍然存在 不變。即使明星崩潰了

  • into a black hole, it would still have angular momentum. We could measure this by firing

    進入一個黑洞,它仍然會有角度 動量。我們可以通過射擊來衡量這個

  • two probes into opposite orbits close to the black hole. Because of their angular momentum,

    兩個探針進入相對的軌道靠近 黑洞。由於他們的角動量,

  • black holes create a spinning current in spacetime. The probe orbiting along with the current

    黑洞在時空中產生旋轉電流。 探測器隨著電流軌道運行

  • will travel faster than the one fighting it, and by measuring the difference in their orbital

    比戰鬥的人旅行得更快, 並通過測量它們的軌道差異

  • periods we can compute the black hole's angular momentum.

    我們可以計算黑洞的時期 角動量。

  • This spacetime current is so extreme it creates a region called the ergosphere where nothing,

    這個時空電流非常極端 一個叫做ergosphere的地區,什麼都沒有,

  • including light, can overcome it. Inside the ergosphere, nothing can stand still. Everything

    包括光,可以克服它。在 - 的里面 ergosphere,沒有什麼可以停滯不前。一切

  • inside this region is dragged along by the spinning spacetime. The event horizon fits

    在這個區域裡面被拖著 旋轉時空。事件視界適合

  • inside the ergosphere, and they touch at the poles. So in one sense, black holes are like

    在ergosphere裡面,他們觸摸到了 極。所以從某種意義上說,黑洞就像

  • whirlpools of spacetime. Once inside the ergosphere, you are caught by the current. And after you

    時空的漩渦。一旦進入ergosphere, 你被當前抓住了。在你之後

  • cross the event horizon, you disappear.

    越過事件視界,你就消失了。

  • One final property of black holes we can measure is electric charge. While most of the matter

    我們可以測量黑洞的最後一個屬性 是電荷。雖然大部分事情都是如此

  • we encounter in our day-to-day lives is uncharged, a black hole may have a net positive or negative

    我們在日常生活中遇到的是不收費的, 黑洞可能有淨正面或負面

  • charge. This can easily be measured by seeing how hard the black hole pulls on a magnet.

    收費。這很容易通過觀察來衡量 黑洞在磁鐵上的拉力有多大。

  • But charged black holes are not expected to exist in nature. This is because the universe

    但預計不會出現帶電的黑洞 存在於自然界中。這是因為宇宙

  • is teeming with charged particles, so a charged black hole would simply attract oppositely

    充滿了帶電粒子,所以充電 黑洞只會吸引人

  • charged particles until the overall charge is neutralized.

    帶電粒子直到整體充電 被中和了。

  • There are 3 fundamental properties of a black hole we can measure - mass, angular momentum,

    黑色有3個基本屬性 我們可以測量的孔 - 質量,角動量,

  • and electric charge. It is believed that once you know these three values, you can completely

    和電荷。據信一次 你知道這三個值,你可以完全

  • describe the black hole. This result is humorously known as theno hair theorem,” since

    描述黑洞。這個結果很幽默 自從被稱為“無毛定理”

  • other than these 3 properties, black holes have no distinguishing characteristics. It's

    除了這三個屬性,黑洞 沒有區別特徵。它的

  • not a blonde, brunette, or a redhead.

    不是金發,黑髮或紅頭髮

  • We now have a good idea of a black hole from the outside, but what does it look like on

    我們現在很好地了解了一個黑洞 在外面,但它看起來像什麼

  • the inside? Unfortunately we can't send a probe inside to take a look. Once any instrument

    裡面?不幸的是我們無法發送 在裡面探測一下。一旦任何儀器

  • crosses the event horizon, it's gone. But! Don't forget we have Einstein's field equations.

    越過事件視界,它已經消失了。但! 別忘了我們有愛因斯坦的場方程。

  • If these correctly describe spacetime outside the black hole, then we can use them

    如果這些正確地描述了時空 在黑洞外,我們可以使用它們

  • to predict what's going on inside as well.

    預測內部發生的事情。

  • To solve the field equations, scientists considered two separate cases: rotating black holes,

    為了解決場方程,科學家們考慮過 兩個獨立的案例:旋轉黑洞,

  • and non-rotating black holes. Non-rotating black holes are simpler and were the first

    和非旋轉黑洞。非旋轉 黑洞更簡單,是第一個

  • to be understood. In this case, all the matter inside the black hole collapses to a single

    要理解。在這種情況下,所有的事情 黑洞內部坍塌成一個單一的

  • point in the center, called a singularity. At this point, spacetime is infinitely warped.

    指向中心,稱為奇點。 此時,時空是無限扭曲的。

  • Rotating black holes have a different interior. In this case, the mass inside a black hole

    旋轉的黑洞有不同的內部。 在這種情況下,黑洞內的質量

  • will continue to collapse, but because of the rotation it will coalesce into a circle,

    將繼續崩潰,但因為 旋轉它會合併成一個圓圈,

  • not a point. This circle has no thickness and is called a ring singularity.

    不是重點。這個圓圈沒有厚度 並稱為環奇點。

  • Black hole research continues to this day. Scientists are actively investigating the

    黑洞研究至今仍在繼續。 科學家正在積極調查

  • possibility that black holes appeared right after the big bang, and the idea that black

    黑洞出現的可能性 大爆炸後,以及黑色的想法

  • holes can create bridges called wormholes connecting distant points of our universe.

    洞可以創建稱為蟲洞的橋樑 連接我們宇宙的遙遠點。

  • We know a great deal about black holes, but there are many mysteries still to be solved.

    我們對黑洞了解很多,但是 還有許多謎團還有待解決。

  • It's a little known fact that all YouTube videos are stored in a special fabric called

    所有YouTube都是一個鮮為人知的事實 視頻存儲在一個名為的特殊結構中

  • playtime. When you watch a video, it sends ripples of energy throughout playtime. And

    播放時間。當您觀看視頻時,它會發送 整個遊戲時間的能量漣漪。和

  • when you subscribe to a channel, it creates a teeny, tiny black hole. So if you like

    當您訂閱頻道時,它會創建 一個小小的黑洞。所以,如果你願意

  • Black Holes, then you know what to do...

    黑洞,然後你知道該怎麼做......

From far away, stars are tiny points of light. But up close, stars are massive, seething,

從遠處看,恆星是微弱的光點。 但近距離,恆星是巨大的,沸騰的,

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影片操作 你可以在這邊進行「影片」的調整,以及「字幕」的顯示

B1 中級 中文 美國腔 黑洞 質量 恆星 軌道 時空 愛因斯坦

黑洞(What is a Black Hole? -- Black Holes Explained)

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    joey joey 發佈於 2021 年 04 月 11 日
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