A definition of the kilogram based on a fundamental constant of nature

I didn’t realize that I was emotionally attached to a chunk of Pt-Ir alloy… anyone else feel uneasy about this?

On the other hand, this is pretty cool and also very shiny.

The article says that the standard kilogram inexplicably has been been losing weight! That is shocking. Enough reason to introduce a more scientific standard that hopefully does not change over time also, because one thing is for sure nothing remains the same in the end…

But how would we know if it did?

I’m fine, either way. Pluto a planet or not a planet, just let me know. I’ll just go with it.

But what’s up with this?

A section of this imaginary line running through Europe was measured painstakingly by hand, inch by inch, in a seven-year journey across the continent.

It’s often pointed out that, for example, the equator is an imaginary line. Aren’t all lines imaginary? I mean I don’t know.

Just yesterday I was standing in line (at least I think I was) at the post office and I had to ask the women in front of me if she was in line or not. I couldn’t tell. If the line is straight then she was not in line, but she would have been in a crooked line. Or a wider line. But if you imagine a line wide enough or crocked enough then I can imagine everyone in town could be in that line.

That what I’d like to know. In there a convention that it is required to explicit say some lines are imaginary? Or am I wrong about the line at the post office?


I think so. If there was a real line out there somewhere how would we notice it? We could be swimming in real lines and never even know it.

Giving it some thought, if you can describe a line in concrete terms, by naming the end points for example, there is no reason to call it imaginary. It’s easy to imagine a straight line between two named points, between first and second base say, or a great circle between two positions. A line described in more vague terms, perhaps it helps to say it’s imaginary.

even if it has a concrete definition, its still an abstract concept.

Yes, but wouldn’t it be redundant or maybe even confusing to call the great circle from say Yokohama to Seattle imaginary? Because once you’ve named the two points it’s easy to imagine. But with the equator, maybe people need a little more help.

Maybe it would be more precise to say ‘invisible’ line.

Anyway, I like the new kg, I feel like if they send me the instructions I could build one at home, as opposed to having one shipped.

It’s basically just a “setup”.

This electromagnetic force is generated using a coil of wire surrounded by permanent magnets. This setup can create two different methods of weighing.

I have come to the conclusion that this forum has finally expired…


This book has a chapter on this and a few more on nautical stuff. It’s a really good read:


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oh! Dear Santa…

… and on the same topic, for what it’s worth:-

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The polar diameter of the planet as a standard of measure is OLD !, It is believed to be incorporated into the VERY slight bend in the pyramid of Cheops’s base which only became known when photographed from the air in recent times at one particular time of day.
A few years after the French attempt to establish the polar diameter (detailed above) it was admitted the error factor was so great as to render the whole project void but due to the costs and the unlikely event of a repeat it was determined to go with what had been established, therefore, the whole metric measuring system is based on actually nothing !!, the standards had to be kept In a room ear absolute zero and were most impractical to utilize.
modern means (from space) have been unable to establish the planets polar diameter any closer than what the American system uses.
I myself, believe the yards, inches (based on fives) to be the superior system … maybe it’s why America decided to use it?
Of course there are the arguments presented in Egyptology and the old bible too.