Why scientists are redefining the kilogram

Re:Why scientists are redefining the kilogram by lmm on Thursday October 26, 2017 @07:00AM (#15557802)

The big issue is that the standard reference kilogram (the block of metal) is losing mass. If we take the SI standards literally, this means e.g. distant galaxies now mass more kilograms than they did last year. Which seems obviously undesirable.

The impact should ultimately be to make ultra-precise physics - and eventually, engineering - easier, because people reproducing an experiment in a different lab will have a closer consensus on exactly how much 1kg is.

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Re:Why scientists are redefining the kilogram by pdpi on Thursday October 26, 2017 @07:07AM (#15557832)

> The big issue is that the standard reference kilogram (the block of metal) is losing mass.

As per the article, there's several of them. Some are losing mass, others are gaining.

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Re:Why scientists are redefining the kilogram by danbruc on Thursday October 26, 2017 @08:44AM (#15558306)

But only one of them, Big K, defines the kilogram. So the ones losing mass might just gain mass more slowly than Big K. Or they might even all be losing mass but some more slowly than Big K making them apparently gain mass. I don't know if we know how the masses actually changed.

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Re:Why scientists are redefining the kilogram by falcolas on Thursday October 26, 2017 @10:10AM (#15558921)

We don't. And that's the problem. If it was a consistent loss, it would be much easier to work around.

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