• From: Denver
  • Registered: 2006-08-25

Topic: Kilogram standard mysteriously losing weight!

Here's an interesting article about the standard for the kilogram mysteriously losing weight.  Any thoughts on this?

The 118-year-old cylinder that is the international prototype for the metric mass, kept tightly under lock and key outside Paris, is mysteriously losing weight -- if ever so slightly. Physicist Richard Davis of the International Bureau of Weights and Measures in Sevres, southwest of Paris, says the reference kilo appears to have lost 50 micrograms compared with the average of dozens of copies.

"The mystery is that they were all made of the same material, and many were made at the same time and kept under the same conditions, and yet the masses among them are slowly drifting apart," he said. "We don't really have a good hypothesis for it."

Source: http://www.cnn.com/2007/TECH/science/09 … index.html

  • From: Northwest of Escondido
  • Registered: 2007-08-29

Re: Kilogram standard mysteriously losing weight!

Interesting..they didn't say what it was made(composition) of or I missed it.  Oddly my first thought is of gravity.... mass should be the same but weight is a factor of gravitational pull ? is it not ? Perhaps I go back to basic science hm..

In search of...
  • From: Denver
  • Registered: 2006-08-25

Re: Kilogram standard mysteriously losing weight!

Yeah, Arfwoo - to the best of my knowledge weight is a factor of gravitational pull.  For example if you drop a feather and a heavy weight from the top of a building, of course the weight would land first.  I'm pretty sure they did mention the material the kilo standard was made of.... as well as an alternative for the measurement.  It is down at the bottom of the article there, see:

Looks like this is what it's made of:

The cylinder was high-tech for its day in 1889 when cast from a platinum and iridium alloy, measuring 1.54 inches in diameter and height

And supposedly this is an alternative for the measurement - though I'm not sure why platinum and iridium alloy also don't have a fixed mass - maybe because they are not one single type of atom?  That's going too far out of my scope of scientific knowledge, but that's the best I can guess.  Nonetheless it seems pretty darn strange to me.  I guess maybe it just took 120 years to start losing mass, but that still wouldn't explain why other prototypes made of the same material, at the same time, kept under the same conditions are not experience the same degeneration.  It's a lil much to comprehend for my unscientific self!

One of the leading alternatives for a 21st-century kilogram is a sphere made out of a Silicon-28 isotope crystal, which would involve a single type of atom and have a fixed mass.

4 Reply by visavis (edited by visavis 2007-09-20 22:33:20)

  • Registered: 2005-10-16

Re: Kilogram standard mysteriously losing weight!

Maybe they've recently hollowed out an underground city just outside of paris.  I'm only half-kidding!  Seriously, gravitational pull can be slightly less if you're standing over a big hollow spot.

Though, that would not explain if all the samples were measured side-by-side, and found to be not matching.

"The unknown does not incite fear, but dependence on the known does." - J. Krishnamurti

visavis's Website

  • From: Australia
  • Registered: 2007-04-07

Re: Kilogram standard mysteriously losing weight!

Reminds me of that popular riddle... "What weighs more?  A ton of steel?  or a ton of feathers?"

Also reminds me, on the subject of 'gravity', that 2 vastly different sized objects of the same density will fall at the same speed under the influence of gravity.   I pulled that one out of that hat that contains old school memories.  Hope i haven't distorted it.  Any physicists around here?

nexus's Website

  • Registered: 2007-09-11

Re: Kilogram standard mysteriously losing weight!

For me this is a great example of how there are no absolutes in the physical realm.  Nothing is permanently fixed or set in stone.  The standards that we measure reality against can change at any time, depending on the will of those who are perceiving it.

  • From: Northwest of Escondido
  • Registered: 2007-08-29

Re: Kilogram standard mysteriously losing weight!

Thanks for the composition note ..couldn't find is yesterday..So my other guess black hole developing.. ?

In search of...

8 Reply by Prances Fences (edited by Prances Fences 2007-09-21 17:10:02)

  • From: Denver
  • Registered: 2006-08-25

Re: Kilogram standard mysteriously losing weight!

visavis wrote:

Though, that would not explain if all the samples were measured side-by-side, and found to be not matching.

I think your theory - which is really interesting - could still be possible.  My understanding is that even though the samples may have been measured side by side, and kept in similar conditions...when the original from Paris was measured against the other 'national prototypes' (which sound like clones that have been used as a reference point for other places all over the world)...then location is the only real variable factor here.  Definitely makes ya wonder what the heck is happening in Paris?  You might just be right - at least your idea makes more sense than anything I've come up with!

nexus wrote:

on the subject of 'gravity', that 2 vastly different sized objects of the same density will fall at the same speed under the influence of gravity.   I pulled that one out of that hat that contains old school memories.  Hope i haven't distorted it.  Any physicists around here?

I'm no physicist but it sounds like you're right on the money to me.  Definitely something to think about! 


Athenais wrote:

For me this is a great example of how there are no absolutes in the physical realm.

Absolutely excellent point!  wink 

Arfwoo wrote:

So my other guess black hole developing.. ?

Wow, I would have never even thought of that!  What's funny is that your idea seems to point along the same lines as visavis' underground base idea...and I definitely think there has to be something specific about the location that is causing this abnormality.

Things that make ya go HMMMM!!!

When I first heard about this, my immediate thought was that it was some sort of evidence of this 'higher density shift' that we've been discussing for so long.  After reading more about it though, I think you guys are definitely on the right track about there being something happening over there.