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  • You're probably familiar with the standard model, a theory of fundamental particles and

    你可能對標準模型很熟悉,這是一個關於基本粒子和的理論。

  • how they interact. These particles have counterparts that are mirror images, or opposite charges,

    它們是如何相互作用的。這些粒子的對應物是鏡像,或相反的電荷。

  • or both. But in the '60s, we discovered particles that were flipped- image and charge versions

    或兩者。但在60年代,我們發現了粒子 那是翻轉的影像和電荷版本

  • of each other didn't always behave how we expected. We've since adjusted our expectations,

    彼此並不總是按照我們的期望行事。我們後來調整了我們的期望。

  • but even so, some of these particles still behave in a way we can't explainIt's

    但即便如此,這些粒子中的一些仍然表現在我們無法解釋的方式。它的

  • what's known as the "strong CP problem," and it's a glaring flaw in the standard

    所謂的 "強CP問題",是標準中一個明顯的缺陷。

  • model. In order to understand the strong CP problem, there's a hierarchy of terms we

    模型。為了理解強CP問題,我們有一個層次的名詞

  • need to make clear so we're all on the same page. First up, we need to review the four

    需要說清楚,這樣我們才會心中有數。首先,我們需要回顧四個

  • fundamental forces. They are gravity, electromagnetism, the weak nuclear force, and the strong nuclear

    的基本力,它們是重力、電磁力、弱核力和強核力。它們是重力、電磁力、弱核力和強核力。

  • force. With the exception of gravity, these forces are mediated by particles in the standard

    力。除重力外,這些力都是由標準的粒子所介導的。

  • model called bosons. The way these forces affect decaying particles starts to get complicated

    稱為玻色子的模型。這些力對衰變粒子的影響方式開始變得複雜起來。

  • when we talk about symmetry. Imagine an unstable particle that, through an electromagnetic

    當我們談論對稱性時。想象一下,一個不穩定的粒子,通過電磁波

  • interaction mediated by photons, decays intodaughterparticles. If you were to take

    由光子介導的相互作用,衰變為 "子 "粒子。如果你要把

  • that unstable particle and flip its charge, what's known as charge conjugation or just

    顛覆其電荷,這就是所謂的電荷共軛或只是

  • C, the charge-flipped particle undergoes electromagnetic interactions in the same way as its antiparticle.

    C、電荷翻轉的粒子與其反粒子一樣發生電磁相互作用。

  • The decay happens at the same rate and with the same properties, meaning electromagnetism

    衰變發生的速度和性質都是一樣的,也就是電磁學。

  • has what's called "C-symmetry."  The same is true if you were to take that unstable

    具有所謂的 "C對稱性"。 同樣的道理,如果你把那個不穩定的...

  • particle and flip all its spatial coordinates to make a mirror image of it, what's known

    粒子,並翻轉其所有的空間座標,使之成為鏡像,這就是所謂的

  • as parity, or P.  A mirror particle will also undergo electromagnetic interactions

    鏡面粒子也會發生電磁相互作用,作為奇偶性,即P。

  • in the same way, or symmetrically, to its regular self. So electromagnetism has "P-symmetry."

    以同樣的方式,或者說對稱的方式,對其規律性的自我。所以電磁學具有 "P對稱性"。

  • And finally, electromagnetic interactions are the same whether we're going forward

    最後,電磁相互作用是一樣的,無論我們是向前走還是向後走

  • in time or back, so they exhibit "T-symmetry." They also are symmetrical with any combination

    在時間上或回溯上,所以它們表現出 "T對稱性"。它們也是對稱的任意組合

  • of C, P, and T, even all three together. So if you have a charge-flipped mirror image

    的C、P、T,甚至三者一起。所以,如果你有一個電荷翻轉的鏡像。

  • of an unstable particle undergoing an electromagnetic interaction backward in time...you still know

    一個不穩定的粒子在電磁作用下向後退的時候......你還知道嗎?

  • what you're going to get. Simple, right? Okay, stop, catch your breath. Let's all

    你會得到什麼。簡單,對吧?好了,停下來,喘口氣。讓我們都

  • take a minute to sit with this new information, because I think you know what's coming next.

    花點時間看看這些新資訊 因為我想你知道接下來會發生什麼事情

  • That's right, it gets more complicated. If our hypothetical unstable particle were

    沒錯,它變得更復雜了。如果我們假設的不穩定粒子是 If our hypothetical unstable particle were

  • instead to undergo radioactive decay mediated by the weak force, then its mirror image version

    而不是在微弱的力的作用下進行放射性衰變,那麼它的鏡像版本

  • wouldn't behave symmetrically every time. It would violate P-symmetry. This was first

    不會每次都表現得很對稱。它將違反P對稱性。這是第一次

  • observed in 1956,  back when we thought parity conservation was the law. So you can imagine

    觀察到1956年,當時我們認為奇偶性保護是法律。所以你可以想象

  • it was quite a shock when scientists observed two arrangements of cobalt-60 decaying differently.

    當科學家們觀察到鈷-60的兩種排列方式衰變不同時,相當震驚。

  • Since then, it's been observed that weak interactions can also violate C- and T-symmetry,

    此後,人們觀察到,弱相互作用也可以違反C對稱性和T對稱性。

  • and any combination of any two, though not C, P, and T altogether. So, after reworking

    和任意兩個的組合,雖然不是C、P、T的全部。所以,經過重新設計

  • the math, the standard model today allows for weak and strong interactions to violate

    數學,今天的標準模型允許弱相互作用和強相互作用違反。

  • all symmetries except CPT altogetherWhich gives rise to a new problem. We've observed

    除了CPT以外的所有對稱性完全。 這就產生了一個新的問題。我們已經觀察到

  • weak interactions that violate CP-symmetry. It doesn't happen often, but it does happen

    違反CP對稱性的弱相互作用。這種情況並不經常發生,但它確實發生了

  • nonetheless. In fact, it happens a lot more than we've seen charge-parity violation

    儘管如此,。事實上,它的發生比我們所看到的電荷對等違反的情況要多得多。

  • in interactions mediated by the strong force. We've seen that a grand total of, drumroll

    在由強勢力量調解的相互作用中。我們已經看到,總共有,鼓聲響起

  • please…. no times. Not once. Kind of disappointing, isn't it? The fact that the strong force

    求你了......沒有次數。一次都沒有有點失望吧?事實上,強大的力量

  • should violate CP symmetry but hasn't as far as we know is called the strong CP problem.

    應該違反CP對稱性,但據我們所知並沒有違反,這就是所謂的強CP問題。

  • But in science, the unexplained is where the fun begins! Because the strong CP problem

    但在科學上,未被解釋的問題才是樂趣的開始!因為強CP問題

  • is such a mathematical improbability, we think there must be something else at play here.

    是這樣一個數學上的不可能,我們認為這裡一定有別的東西在起作用。

  • In the '70s, scientists Roberto Peccei and Helen Quinn proposed that maybe there's

    70年代,科學家Roberto Peccei和Helen Quinn提出,也許有

  • some undiscovered parameter, like a field that inhibits strong CP violation. If this

    一些未被發現的參數,比如一個抑制強CP違反的場。如果這個

  • field exists, then there should be a particle called an axion to go with it. Axions should

    場的存在,那麼就應該有一種叫做軸子的粒子與之配合。軸子應該

  • be chargeless, very light, and incredibly abundantHmm, a particle that's hard to

    是無電的,很輕的,和令人難以置信的豐富。嗯,一個粒子,很難

  • find and doesn't interact with anything except through gravity? Sounds like another

    找到並不與任何東西相互作用,除了通過重力?聽起來像另一個

  • candidate for dark matter to me. Indeed, since the 1980s, scientists have been hunting for

    暗物質的候選者對我來說。事實上,自20世紀80年代以來,科學家們一直在尋找

  • axions in labs. As you might have guessed, we haven't found them yet, but we're still

    實驗室裡的軸子。你可能已經猜到了,我們還沒有找到它們,但我們仍在

  • looking for them with research like the ADMX-G2 Experiment. Axions are not the only possible

    通過ADMX-G2實驗等研究來尋找它們。軸子不是唯一可能的

  • solution to the strong CP problem, and when we eventually do figure out why this expected

    強CP問題的解決方案,而當我們最終弄清楚為什麼這個預期的?

  • unexpected event...isn't...occurring, it'll be exciting to see where physics takes us

    意外事件... ...是不是... ...發生,這將是令人興奮的看到物理學帶我們到哪裡去

  • next.

    下一個。

  • If the search for axions and their relation to dark matter has piqued your curiosity,

    如果尋找軸子及其與暗物質的關係引起了你的好奇心。

  • check out this Focal Point episode on how today's scientists are attempting to hunt

    請看本期Focal Point的節目,講述當今科學家如何試圖獵取。

  • them down. Don't forget to subscribe, and keep coming back to Seeker for all of the

    他們下來。不要忘了訂閱,並繼續回到Seeker來獲取所有的。

  • latest science news. Thanks for watching, and I'll see you next time!

    最新科學新聞。感謝您的觀看,我們下期再見!

You're probably familiar with the standard model, a theory of fundamental particles and

你可能對標準模型很熟悉,這是一個關於基本粒子和的理論。

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This Missing Force Field Could Lead to a Dark Matter Breakthrough

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    Summer 發佈於 2020 年 08 月 31 日
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