为什你的耳机总是缠绕打结

It happens every time: You reach into your bag to pull out your headphones. But no matter how neatly you wrapped them up beforehand, the cords have become a giant Gordian knot of frustration.

有件事似乎无所不在：你把手伸到包包里拿出你的耳机，但是无论之前你把耳机缠得如何整齐，耳机线总是会结成一个十分混乱的结。

Along with your Netflix stream inexplicably buffering and Facebook emotionally manipulating you, tangled cords are the bane of modern existence. But until we invent a good way of wirelessly beaming power through the air to our beloved electronic devices, it seems like we’re stuck with this problem.

除了Netflix的让人莫名其妙的流媒体加载技术和Facebook对用户的情绪控制实验之外，绕线耳机也应该算反现代科技的一个存在。但是除非我们能发明一种比较好的无线辐射技术用于通过空气介质来连接我们所钟爱的电子设备，否则我们只能继续忍受这个问题了。

Or maybe we can fight back with science. In recent years, physicists and mathematicians have pondered why our cords are such jerks all the time. Through experiments, they have learned there are many interesting ways to explain the science of knots. In 2007, researchers at the University of California, San Diego tumbled pieces of string inside boxes in an effort to find the ways that a cord can become tangled as it wanders around in your backpack. Their paper, “Spontaneous knotting of an agitated string,” helps explain how random motions always seem to lead to knotting and not the other way around.

或者我们能用科学予以还击。近年来，物理学家和数学家一直在反复研究有线耳机的缠绕问题。通过实验，科学家们发现有许多途径能够解释绳结科学。2007年，美国加利福尼亚大学的研究员在盒子里放置了许多线绳并摇晃盒子，以观察研究为什么耳机线在你的包里随便缠绕乱作一团的原因。他们的论文，“上下摆动的线绳能自然地打结”也解释了为什么随意的摇动总能让线绳打结，而不是有其他动作。

Long floppy pieces of string can assume many spontaneous configurations. A string could be nicely laid out in a straight line. Or it could have one end crossed over some section in the middle. There in fact happen to be a lot of configurations where the string wraps around itself, potentially creating a tangle and eventually a knot. With relatively few of these random configurations being tangle free, chances are higher that the string will be a mess. And once a knot forms, it’s energetically difficult and unlikely for it to come undone. Therefore, a string will naturally tend toward greater knottiness.

长而松散的线绳能随机形成许多形状。一条线绳能被拉成直线，当然也也能从中间开始交错盘桓。实际上，当线绳自己缠绕起来之后，就能形成各种不同的形状，而这也为线绳乱缠乱绕甚至打结创造了一个潜在的契机。只要有几根这种不同形状的线绳互相交结在一起，那么线绳胡乱打结的几率将会大大提高。一旦出现了一个结，那么再把它解开就很困难了，甚至是不可能的。因此，自然而然地，一条线绳就总会比较容易打结。

Humans have been tying things up with string for many thousands of years, so it’s no surprise mathematicians have been working on theories of knots for a long time. But it wasn’t until the 1800s that the field really took off, when physicists like Lord Kelvin and James Clerk Maxwell were modeling atoms as spinning vortices in the luminiferous ether (a hypothetical substance that permeated all space through which light waves were said to travel). The physicists had worked out some interesting properties of these knot-like atoms and asked their mathematician friends for help with the details. The mathematicians said, “Sure. That’s really interesting. We’ll get back to you on that.”

人类用线绳捆系东西的习惯已经维持上千年，因此数学家们长久以来研究绳结的理论这事情一点也不稀奇。但是直到诸如开尔文男爵和詹姆斯·克拉克·麦克斯韦利用原子建模描述以太（一种假象的无所不在的光波传播介质）介质中的漩涡流的19世纪，这一领域才有所突破。物理学家们发现了这种类似绳结的球棍原子模型的一些有趣的性质，并找来他们的数学家朋友在细节上予以他们帮助。数学家们说：“行，这还真挺有趣，我们来帮你们吧。”