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An old artifact kept in a vault outside Paris is no longer the standard kilogram

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Re: An old artifact kept in a vault outside Paris is no longer the standard kilogram

#151

Post by shpx »

cies wrote: post #85
shpx wrote: post #34

Earlier quoted context omitted.

If you were emperor of the world, I would implore you to finance a multibillion dollar project to measure the gravitational constant to higher percision so that we could move to units that actually make sense. https://en.wikipedia.org/wiki/Planck_units

Came here to mention the Planck units, aka God's units :) Sadly they are a little outside of the human realm of experience, both in their single units (waaay to small usually) and in the units that the list contains (speed, electrical charge, etc; where we like "introductory" units such as length, time, weight)

The units aren't "waaay too small", it's the humans that are big.

Realistically, we might also have shorthands for a convenient order of magnitude for each of the units

http://www.ihst.ru/personal/tomilin/papers/tomil.pdf

but these types of decisions should probably be left for whenever people can economically measure the constants with enough precision to be serious about switching.

Re: An old artifact kept in a vault outside Paris is no longer the standard kilogram

#152

Post by garmaine »

apt-get wrote: post #146
garmaine wrote: post #60

Earlier quoted context omitted.

> Megatons, as in yield of nuclear weapons. Which is a bit odd unit, should be in J, goddammit! That’s what is odd about it? It should be teragrams.

Yield of explosives is generally measured in kilograms of TNT, that's why.

Whoosh.

Re: An old artifact kept in a vault outside Paris is no longer the standard kilogram

#153

Post by bpye »

anoncake wrote: post #82
vincnetas wrote: post #17

Earlier quoted context omitted.

More like from JPG to SVG

Not JPG, a physical picture that cannot be copied perfectly.

If you consider re-encoding a JPG perhaps the initial comparison holds.

Re: An old artifact kept in a vault outside Paris is no longer the standard kilogram

#154

Post by no_identd »

snops wrote: post #58
rimliu wrote: post #44

Earlier quoted context omitted.

How do you imagine that? And what has the bit to do with it?

The SI units are supposed to be used to define all other units. The mole is just a unitless number which isn't used for many definitions, while the bit (or preferably, Shannon) has a fundamental use in information theory and the wider field of physics. The mole is a human specific number, the bit is a property of the universe. Information is a physical quantity, just like mass or length, and deserves to have a unit i…

"The smallest=the most elegant=the most desirable" seems like terrible reasoning, and similar to the reasoning behind the infamous 'Uno':

https://en.wikipedia.org/wiki/Parts-per_notation#Uno

However, I don't entirely disagree with where you go with this, but in my opinion, one ought to:

1. Use the nat an normalize everything else (which might seem like an odd idea at first, but think about it):

https://en.wikipedia.org/wiki/Nat_%28unit%29

But, if we assume you want to avoid the normalization, then it would seem more sensible, due to numerical efficiency, to use balanced ternary, which actually has, unlike what people who rather cluelessly apply the literal textbook (and terrible) metric of 'Radix efficiency'(an entirely artificial measure originally invented to account for engineering concerns related to vacuum tube spacing.) would presume, higher numeric efficiency than unsigned ternary, as shown here by a then Indian computer science student, Abhijit Bhattacharjee, whose work on this unfortunately only remains accessible via the Internet Archive Wayback Machine:

https://web.archive.org/web/20090312094241/http://abhijit.in...

He actually got a reply by Marvin Minsky(to an email he had sent him) at some point (also available via archive.org, but only if you do a lot of trickery which I can't do from my mobile phone, I've however previously verified the quote he provided on the bottom of the page and it does, by all things I could account for, indeed seem genuine), which I'll quote here:

"Yes it is a fascinating subject, and your explorations and descriptions are extremely readable. I hope it gets the interest of more mathematicians."

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