经济学人172:基础物理学 反物质现状

 　　Science and technology

　　科学技术
　　Fundamental physics
　　基础物理学
　　Antimatter of fact
　　反物质现状
　　Researchers at CERN have held on to anti-atoms for a full quarter of an hour
　　欧洲核子研究中心的研究人员已经让反原子停留了十五分钟。
　　READERS who were paying attention in their maths classes may recall that quadratic equations often have two solutions, one positive and one negative.
　　关注数字课的读者们或许会想到二次方程通常会有两个解，一个是正值，一个是负值。
　　So when, in 1928, a British physicist 1 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，一个名叫保罗·狄拉克的英国物理学家给出了有关电子的一个方程的解，然而事实上，这个结果表达的是一种相反的粒子，这个结果或许会被考虑后舍弃。
　　But it wasn't.
　　然而事实并非如此。
　　Instead, Dirac interpreted it as antimatter—and, four years later, it turned up in a real experiment.
　　相反，狄拉克将其解释为反物质—并且在四年后，在现实的实验中验证了它的存在。
　　Since then antimatter—first, anti-electrons, known as positrons, and then antiversions of all other particles of matter—has become a staple 2 of both real science and the fictional 3 sort.
　　从那时起，反物质—最初是反电子，也就是俗称的质子，接着就是其他粒子的反物质—这已经成了现实科学和虚构类别之间的主要组成部分。
　　What has not been available for study until recently, however, is entire anti-atoms.
　　这样的研究一直以来没有突破直到最近的完全的反原子的出现。
　　A handful have been made in various laboratories, and even held on to for a few seconds.
　　在各个实验室已经有一小部分的反原子被发现，即便它们仅仅存在了几秒钟的时间。
　　But none has hung around long enough to be examined in detail because, famously, antimatter and matter annihilate 4 each other on contact.
　　不过没有一个停留了足够长的时间用以仔细地研究他们，众所周知，反物质与物质只要相遇就会湮灭。
　　But that has now changed, with the preservation 5 of several hundred such atoms for several minutes by Jeffrey Hangst and his colleagues at CERN, the main European particle-physics laboratory near Geneva.
　　然而随着在欧洲核子研究中心这个在日内瓦附近主要的欧洲粒子物理实验室里，该机构的杰弗瑞?汉斯特与其同事让数百个这样的原子维护了几分钟，原来的情况现在已有所改观。
　　The reason this is important is that Dirac's equation is misleading.
　　狄拉克方程是一种误导这个原因是很重要的一点。
　　Antimatter cannot be the perfect opposite of matter, otherwise neither would exist at all.
　　反物质并不是完全的反物质，否则它将无法存在。
　　If they truly were perfect opposites, equal amounts of the two would have been made in the Big Bang,
　　如果实际上它们是完全相反的，那么相同的数量的反物质早在大爆炸产生时就已经互相湮灭了，
　　and they would have annihilated 6 each other long since, leaving only light and other forms of electromagnetic radiation to fill the universe.
　　它们只以电磁波的形式留在宇宙中。
　　That galaxies 7, stars and planets—and physicists 8 to ponder such things—exist therefore means there is a subtle asymmetry 9 between matter and antimatter, and that nature somehow favours the former.
　　星系，恒星以及行星——物理学家在在仔细思考这样的事情—它们都已经存在了，这意味着在物质与反物质之间有着一些不可思议的不对称性，自然界在某种程度上是偏爱于前者。
　　Two such asymmetries 10 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.
　　两个这样的不对称性实际上已经被发现了。不过二者都不足以解释为什么如此多的物质存活了下来。对于整个反原子的研究或许能够提供进一步的线索。
　　Last November the ALPHA collaboration 11 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，欧洲核子研究中心由汉斯特博士领导的阿尔法项目成功地将正电子放入了38个反质子周围的轨道中—因此形成了反氢原子—接着将它们放入了一个磁阱，持续了零点几秒。
　　Now, as they report in Nature Physics, the researchers have used their device to preserve anti-hydrogen for 16 minutes .
　　随着他们在《自然—物理学》发布报告，研究人员又利用他们的设备维持了反氢原子16分钟。
　　This gives the anti-atoms plenty of time to settle into their ground state, the most stable condition a particle or atom can attain 12.
　　这让反原子有充足的时间待在基态—这是一个粒子或原子能够达到的最稳定状态。
　　As a result, Dr Hangst and his colleagues can look in a leisurely 13 manner for novel ways that antimatter might differ from the common-or-garden variety.
　　因此汉斯特博士和他同事凭这种新奇的方式有充足的时间来观察反物质—这或许不同于平日的各种状态。
　　Their first experiment will involve nudging the trapped anti-atoms with microwaves.
　　他们的第一次实验将会用不同频率微波轻推被困的反原子。
　　If the frequency of these microwaves is just right, they will flip 14 an anti-atom's spin.
　　如果这些微波的频率恰到好处，他们将会使这些反原子产生自旋翻转。
　　That reverses the polarity of the atom's magnetic field and ejects it from the trap.
　　这就会改变原子原来的极性和磁场，原子就会从磁阱中弹出去。
　　The frequency needed to do this can then be compared with that which flips 15 the spin of an ordinary hydrogen atom.
　　这些测试的频率将会与翻转普通氢原子的频率作对比。
　　If the two turn out to be different, it will point towards the nature of the mysterious cosmic asymmetry.
　　如果两个频率是不同的，那么它将会指向神秘的宇宙不对称性。
　　Besides being of huge interest, such a result would also have a pleasing symmetry of its own.
　　除了巨大的兴趣外，这样的结果对于本身也将是一个值得欣喜的对称。
　　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.
　　反物质的独特发现是理论预示未知世界这一说法的一个极好说明。这使得预测未知理论来获得人类的满意将成为一个事实。
　　1.fundamental a.基本的；根本的
　　For something fundamental has changed in Venezuela.
　　因为在委内瑞拉，有一些基本的东西已经改变了。
　　2.equation n.相等；均衡
　　I can't make this equation come out.
　　我不会解这个方程式。
　　3.particle n.颗粒；微粒；极小量
　　We can see the dust particles floating in the sunlight clearly.
　　我们可以很清楚地看到阳光下的灰尘颗粒。
　　4.experiment n.试验；实验
　　The researchers are repeating the experiment on rats.
　　研究人员用老鼠反覆做该试验。
　　5.available a.可利用的；可得到的
　　Do you have a room available?
　　你们有空房间吗？