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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

• 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

B1 中級 中文 粒子 電荷 作用 鏡像 觀察到 重力

# 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