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科学家将重新定义“千克”

kira86 于2018-11-21发布 l 已有人浏览
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在今年国际计量大会上,科学家们一致投票决定告别古老的定义千克的方法,他们会采用普适常数作为基准的新测量体系。采用了将近140年的方法将成历史。
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Scientists to Reboot the Kilogram

科学家将重新定义“千克”

This is a copy of the lump of metal which since 1879 has been single-handedly responsible for telling the world exactly how much a kilogram weighs.

这是一块铂铱合金圆柱体,自1879年来,该圆柱体就成为了国际单位“千克”的唯一基准。

But many of the world's scientists worry that this metal cylinder currently stored in a French lab carries too much weight unintended.When you just get it out of the vault, it's slightly dirty.But the whole process of cleaning or handling or using the mass can change its mass.So it's not the most, not the best way perhaps of defining mass.It's been very good for the last 130 years, but it's also a single point of failure in our entire mass system.

但是来自全球各地的科学家担心,随着时间增长,这个目前保存于一间法国实验室的金属圆柱体的重量发生了意料之外的变化。每次把它从保险库里拿出来的时候,它都会轻微的沾染灰尘。那么把它打扫干净、或者拿取或是使用其测质量的时候,它的质量都会发生变化,所以这并不是定义质量最好的方法。在过去的一百三十年内,用这种方法定义质量是很不错的,但其同时也是我们整个质量系统里的一个单点故障。

In a vote this Friday, scientists from the General Conference on Weights and Measures are expected to vote unanimously to say goodbye to that kilogram weight.They will adopt a new measuring system based on universal constants,the scientific term for things that never change, like gravity or the speed of light. A kilogram will still be a kilogram, but like the speed of light, it can't ever change.There will be absolutely no change whatsoever, and it's taken an enormous amount of effort and agreement to get to that point.

本周五召开的国际计量大会上,科学家们将一致投票决定告别这种定义千克的方法。他们将会采用一种以普适常数作为基准的新测量体系,普适常数这一术语指重力或光速等永不改变的常量。一千克依旧代表一千克,但是就像光速一样,这个数值永远都不会改变。这个数值无论如何都不会发生改变,要实现这一点确实要花费巨大的努力,还要获得大家的一致认可。

So why do it? Because no matter how precise the measurements of that lump of metal in France,its weight has changed ever so slightly over time.It's never perfect.And when engineers deal with weight on a smaller and smaller scale,that little imperfection becomes a huge imperfection called an uncertainty in scientific terms.And big uncertainties can make things like the tiny microchip in your new phone less precise and less efficient.We need to be met...to be able to measure at different scales because the uncertainties built up very, very quickly.The new system means no more uncertainty.And scientists say that will help clear the way for new more advanced technology in the future.

那么为什么一定要这么做呢?因为不论放在法国的这个金属块测量有多么精确,它的质量随着时间变化一直在轻微发生改变,永远都不是最完美的那个数值。所以当工程师在非常非常小的范围内涉及到质量问题时,这种微小的不精确就会凸显成为非常严重的不精确,术语称为不确定性。这种极大的不精确会导致像新手机的微型芯片这样的物品越来越不精确,效果越来越差。我们需要……我们需要能够在不同的尺度上进行测量,因为不确定性的累积非???。新的测量体系意味着不再存在不确定性??蒲Ъ页普饨蠢吹母咝驴萍挤⒄棺龊米急?。

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美国之音记者Kevin Enix报道。

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