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为什么你的耳机总打结
Why are your headphones always in a knot
有时候耳机真的是最烦人的
Sometimes,headphones are just the worst.
每次我都想
It seems like every time I want to
拿出耳机戴好去跑步
whip out my earbuds and go for a run,
我总得停下来去解一大团乱糟糟的耳机线
I’m stuck untangling a huge knotted mess.
我发誓我都有好好收好它们 然并卵
I swear I try to keep them organized, but nothing seems to work.
不管你信不信 科学家们曾研究过这个现象
Believe it or not, scientists have studiedthis phenomenon before
或者说做过类似的研究
or at least something like it.
他们发现
And they’ve found
几根线放在一起晃动几秒钟就会自然而然地打结
that pieces of string naturally form knots within seconds of being agitated.
显然 这说明
So clearly, there’s a reason
不是只有我的耳机线会缠在一起
I’m not the only one suffering from headphone tangles.
但是好消息是 这些发现也提出了解决办法
But better yet, these findings also pointto a solution
让我们能够彻底告别每天解耳机线的烦恼
that just might end our days of untangling cords once and for all.
这个解结的实验可以追溯到2007年
The knotty experiment dates back to 2007,
加州大学圣地亚哥分校的一个物理学家和一个有幸被选中的学生
when a physics professor at UCSD and a luckyundergraduate
决定研究一下绳子自己打结的方式
decided to find out exactly how strings make a mess of themselves.
他们将一些长度和硬度各不同的绳子
They dropped strings of various lengths and stiffnesses
放进一个塑料箱子
into a plastic box,
然后以不同的速率 花不等的时间去晃动这个箱子
which they then spun at various speeds and for various amounts of time.
再使用计算机精确的统计了打结的类型
Using a computer, then they meticulously cataloged the types
每发现不同的打结类型
of knots, if any,
他们就会使用数学里扭结理论的方法做出统计
that resulted, using a branch of mathematics called knot theory to guide them.
扭结理论有各种各样的应用 从物理学到生物学
Knot theory has all sorts of applications,from physics to biology,
而且它同时也有助于理解
but it’s also good
使东西缠成一团的方式和原因
for just understanding how and why stuff gets tangled up.
在扭结理论中 会以闭合的绳环来研究各种结
In knot theory, knots are always studied asclosed loops,
所以在这个实验中当绳子被弄乱后
so after the strings in this experiment gotjumbled,
两头就会捆在一起成了一个圆圈
the two ends were tied together to form acircle.
在这些基础性的实验中 两人进行了超过3400次的反复测试
From these basic experiments, which includedmore than 3400 test drops,
他们从中发现了一些现象
the duo discovered a couple of things,
比如 让绳子打结不需要花很多时间
like the fact that it doesn’t take much to get a knot.
仅仅10秒内 加以10次的晃动
In just 10 seconds, with 10 rotations,
大约有一半的绳子就会打结在一起
about half of the strings formed knots.
所以不要再自责了 耳机打结是件很自然的事
So don’t beat yourself up, knots just happen. Strangely,
奇怪的是 这些几乎都是大的 单个的结
these knots were almost all big,single knots
数学家称之为素数结
what mathematicians call prime knots
而两端都有两结的结
instead of strings with two knots, say, ateither end,
他们称之为复合结
which they call composite knots.
如果没做这个实验 研究人员会假设这两种类型都有可能发生
Without doing the experiment, researchers would have assumed both types were possible.
但相反 事实上这些绳子反而更倾向于用相同的方式
But instead, they tended to tie themselves up the same way,
一次又一次地缠在一起
over and over.
首先 他们会先缠绕 行成环状
First, they’d coil up, creating some loops.
然后 有一些重叠的股
Then some of the overlapping strands
会相互交叉
would work their way across one another,
行成一种辫子的样子
forming a kind of braid.
取决于交叉的数量
Depending on the number of crossings,
比如在进行11次交叉后
which happened as many as 11 times,
形成的结就会非常复杂难解
the knots could get very complex.
所以现在我们知道了结形成的方式方法
So we know these knots happen, and how,
那我们有望脱离被耳机线支配的恐惧吗
but is there any hope for those of us plagued by headphone tangles?
研究人员发现
Well, the researchers noticed that the chance
容易打结的总是那些
of a knot forming generally went up
比较长的
if the string was longer in length,
或者纠缠在一起时间比较久的绳子
or spun for a longer length of time.
但如果旋转的速度非常快
But if it was spun too fast,
绳子们就没有机会搅和到一起
the strings weren’t allowed to tumble,
那打结的概率就下降了
and the probability of a knot went down.
而偏硬一点的绳子同样也不容易打结
Stiffer string also decreased knot potential.
为了减少绳子的活动空间
Giving the string less space
而减小盒子的尺寸也会使
by reducing the box size also made it much harder
绳子不容易打结 有趣的是
for the knots to form. Weirdly,
研究人员认为空间不够
not enough space is also the
同时也是脐带结非常罕见的原因
reason doctors think umbilical cord knots are very rare
因为羊膜囊空间太小 脐带在其中难以打结
the amniotic sac is just too tiny for much knotting to occur.
因此 理论上认为避免耳机线打结的办法
So, your math-approved way of avoiding tangledearbuds
就是把它们放到一个很小的空间里
is to just tuck them away in a tiny space,
再用东西包住 这样它们就安分了
ideally wrapping them around something sothey can’t jiggle at all.
如果这还不行 好吧 那也许下一次
And if all that doesn’t work, well, maybenext time
你就会对你耳机线打出的奇妙而复杂的结感到惊奇
you can just marvel at the wonderful complexity of your knot instead.
天知道这些结怎么这么牛批
Who knew knots were so amazing?
如果你是个会编织的人 我相信你一定会知道的
I bet you did, if you’re a knitter.
我所在的蒙大拿州已经开始变冷了
It’s already starting to get cold whereI live in Montana,
这个季节绝对是帽子和围巾的天下
so it’s definitely hat and scarf season.
如果你已经做好
If you’re ready to
窝在家里的准备并打算尝试一项新手艺
snuggle indoors and try out a new craft,
不妨给自己织一条围巾
you can knit yourself a scarf
你可以去Skillshare分享平台观看Davina Choy的新手编织教程
in Davina Choy’s Knitting Basics class on Skillshare.
从中可以学习到几种基本技巧以及解决一些常见错误的方法
You’ll learn several basic techniques andhow to troubleshoot common mistakes.
学成后 你的脖子就再也不怕冷啦
And at the end, you’ll have a cozy neck!
现在Skillshare送给所有科学秀的观众两个月免费的体验课程
Right now Skillshare is offering SciShow viewerstwo months
超过20000个兼具原创性和实用性的课程都可以免费观看
of unlimited access to over 20,000 creative and technical classes for free.
点击视频下方链接
Follow the link
获取Davina Choy的课程
in the description to check out Davina Choy’s classes
还有其他海量视频
as well as thousands of others.
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