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Science and technology
科學技術
Fundamental physics
基礎物理學
Antimatter of fact
反物質現狀
Researchers at CERN have held on to anti-atoms for a full quarter of an hour
歐洲核子研究中心的研究人員已經讓反原子停留了十五分鐘。
READERS who were paying attention in their maths classes may recall that quadratic equations often have two solutions, one positive and one negative.
關注數字課的讀者們或許會想到二次方程通常會有兩個解，一個是正值，一個是負值。
So when, in 1928, a British physicist called Paul Dirac solved such an equation relating to the electron, the fact that one answer described the opposite of that particle might have been brushed aside as a curiosity.
因此在1928年，一個名叫保羅·狄拉克的英國物理學家給出了有關電子的一個方程的解，然而事實上，這個結果表達的是一種相反的粒子，這個結果或許會被考慮后舍棄。
But it wasn't.
然而事實并非如此。
Instead, Dirac interpreted it as antimatter—and, four years later, it turned up in a real experiment.
相反，狄拉克將其解釋為反物質—并且在四年后，在現實的實驗中驗證了它的存在。
Since then antimatter—first, anti-electrons, known as positrons, and then antiversions of all other particles of matter—has become a staple of both real science and the fictional sort.
從那時起，反物質—最初是反電子，也就是俗稱的質子，接著就是其他粒子的反物質—這已經成了現實科學和虛構類別之間的主要組成部分。
What has not been available for study until recently, however, is entire anti-atoms.
這樣的研究一直以來沒有突破直到最近的完全的反原子的出現。
A handful have been made in various laboratories, and even held on to for a few seconds.
在各個實驗室已經有一小部分的反原子被發現，即便它們僅僅存在了幾秒鐘的時間。
But none has hung around long enough to be examined in detail because, famously, antimatter and matter annihilate each other on contact.
不過沒有一個停留了足夠長的時間用以仔細地研究他們，眾所周知，反物質與物質只要相遇就會湮滅。
But that has now changed, with the preservation of several hundred such atoms for several minutes by Jeffrey Hangst and his colleagues at CERN, the main European particle-physics laboratory near Geneva.
然而隨著在歐洲核子研究中心這個在日內瓦附近主要的歐洲粒子物理實驗室里，該機構的杰弗瑞?漢斯特與其同事讓數百個這樣的原子維護了幾分鐘，原來的情況現在已有所改觀。
The reason this is important is that Dirac's equation is misleading.
狄拉克方程是一種誤導這個原因是很重要的一點。
Antimatter cannot be the perfect opposite of matter, otherwise neither would exist at all.
反物質并不是完全的反物質，否則它將無法存在。
If they truly were perfect opposites, equal amounts of the two would have been made in the Big Bang,
如果實際上它們是完全相反的，那么相同的數量的反物質早在大爆炸產生時就已經互相湮滅了，
and they would have annihilated each other long since, leaving only light and other forms of electromagnetic radiation to fill the universe.
它們只以電磁波的形式留在宇宙中。
That galaxies, stars and planets—and physicists to ponder such things—exist therefore means there is a subtle asymmetry between matter and antimatter, and that nature somehow favours the former.
星系，恒星以及行星——物理學家在在仔細思考這樣的事情—它們都已經存在了，這意味著在物質與反物質之間有著一些不可思議的不對稱性，自然界在某種程度上是偏愛于前者。
Two such asymmetries have indeed been found. But neither is big enough to explain why so much matter has survived. Being able to look at entire anti-atoms might give some further clue.
兩個這樣的不對稱性實際上已經被發現了。不過二者都不足以解釋為什么如此多的物質存活了下來。對于整個反原子的研究或許能夠提供進一步的線索。
Last November the ALPHA collaboration at CERN, which Dr Hangst leads, managed to put positrons into orbit around 38 antiprotons—thus creating anti-hydrogen atoms—and then held on to them in a magnetic trap for a few tenths of a second.
去年11月，歐洲核子研究中心由漢斯特博士領導的阿爾法項目成功地將正電子放入了38個反質子周圍的軌道中—因此形成了反氫原子—接著將它們放入了一個磁阱，持續了零點幾秒。
Now, as they report in Nature Physics, the researchers have used their device to preserve anti-hydrogen for 16 minutes .
隨著他們在《自然—物理學》發布報告，研究人員又利用他們的設備維持了反氫原子16分鐘。
This gives the anti-atoms plenty of time to settle into their ground state, the most stable condition a particle or atom can attain.
這讓反原子有充足的時間待在基態—這是一個粒子或原子能夠達到的最穩定狀態。
As a result, Dr Hangst and his colleagues can look in a leisurely manner for novel ways that antimatter might differ from the common-or-garden variety.
因此漢斯特博士和他同事憑這種新奇的方式有充足的時間來觀察反物質—這或許不同于平日的各種狀態。
Their first experiment will involve nudging the trapped anti-atoms with microwaves.
他們的第一次實驗將會用不同頻率微波輕推被困的反原子。
If the frequency of these microwaves is just right, they will flip an anti-atom's spin.
如果這些微波的頻率恰到好處，他們將會使這些反原子產生自旋翻轉。
That reverses the polarity of the atom's magnetic field and ejects it from the trap.
這就會改變原子原來的極性和磁場，原子就會從磁阱中彈出去。
The frequency needed to do this can then be compared with that which flips the spin of an ordinary hydrogen atom.
這些測試的頻率將會與翻轉普通氫原子的頻率作對比。
If the two turn out to be different, it will point towards the nature of the mysterious cosmic asymmetry.
如果兩個頻率是不同的，那么它將會指向神秘的宇宙不對稱性。
Besides being of huge interest, such a result would also have a pleasing symmetry of its own.
除了巨大的興趣外，這樣的結果對于本身也將是一個值得欣喜的對稱。
The original discovery of antimatter was a nice example of theory predicting an undiscovered fact. This would be a fact that repaid the compliment by predicting an undiscovered theory.
反物質的獨特發現是理論預示未知世界這一說法的一個極好說明。這使得預測未知理論來獲得人類的滿意將成為一個事實。
