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Roundest Object In the World Created
holy_calamity writes "An international research group has created the most perfect spheres ever made, in a bid to pin down a definition of the kilogram. It should be possible to count exactly the number of atoms in one of the roughly 9cm silicon spheres to define the unit. Currently the kilogram is defined only by a 120-year-old lump of platinum in Paris, but its mass is changing relative to copies held elsewhere. Other SI units have more systematic definitions."
Did anyone else read "An international research group has created the most perfect spheres ever made" and think boobs?
"Quote me as saying I was mis-quoted." -Groucho Marx
No mere human will never be able to accomplish what God did with Jennifer Lopez's ass.
SJW: Someone who has run out of real oppression, and has to fake it.
No one will be able to claim that a game of pool, snooker or soccer was won because the ball wasn't round enough...
Summation 2
Does anyone here want to inform CmdrTaco that boobs shouldn't be perfectly spherical, and in fact, it's preferable if they're not?
It's not his fault. He watched a lot of Baywatch. He doesn't know any better.
Those who believe the Internet is private,
find their privates are on the Internet.
Of course, I'm no experimental physicist, but if I were to guess, I might suggest the fact that the binding energy (and thus the mass) might change with force-field fluctuations in the vicinity, but I think that problem should be solvable by defining the proper environment for measuring.
Does anyone know?
The picture in the article shows the sphere being handled in what obviously isn't a cleanroom. Won't that mess up its surface?
"I bless every day that I continue to live, for every day is pure profit."
In a press release today, Sir Mix-A-Lot is quoted as saying that, by viewing this object, "You get sprung", as well as "[wanting to] pull up tough" because of the perfect shape of the object.
He was later quoted as saying that "I like'em round and big, And when I'm throwin a gig, I just can't help myself". Clearly, he is an aficionado for perfectly round objects.
* my captcha was "beating", which is what I deserve for the 90's reference.
In other news... these same scientists are hosting the BEST GAME OF PONG EVER this weekend!
"Insanity in individuals is something rare - but in groups, parties, nations and epochs, it is the rule."
So the metric system, which is touted as being so much more accurate than the measurements we here in the U.S. know and love is has a measurement that is based on a disappearing lump of metal? The only logical conclusion one can draw from this disclosure is that the metric system is magic, and should be burned at the stake.
So I'm not getting fatter, it's the kilogram that's getting slender!
"First we create a perfect sphere, then we count the number of atoms exactly - and we get a kilogram standard!"
"Alright... so how big do we make this sphere?"
"Oh you know.. roughly 9 cm, give or take."
why not just define a kg as 1 Liter of pure H2O at 4deg C?....it is that way anyway.
Your balls may always rotate
Deiseil or widdershins
What matters is their smoothness
Reflects what's on your chins.
Burma Shave
Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
Does this also pin down the value of pi? I mean, they know exactly how many silicon atoms are on the surface of the sphere, and they know exactly how many atoms there are from the center to the surface.
hmm.
A kilogram is defined as exactly 2.20462262 pounds of pure water at pressure of 100 kPa (1 bar) and a temperature of 273.15 K. :)
The roundescht object in the world isch your mother, Trebek.
Colin Dean Go a year without DRM
Well, it's sorta like this: a standard is only useful if you have some effective way to reproduce it or measure with it.
1. time. You can essentially just make a MASER, which means basically a cavity which resonates at that frequency. The nice part is that it can be tuned, and even continuously tuned, by just measuring the amplitude of the signal. When you've reached the maximum power, the thing is tuned to that frequency.
2. length. It's measured by Interferometry, so you have a meaningful way to transform a wavelength into any given distance.
At any rate, the transition for these two only happened when someone build a device which could actually measure one second or one metre that way.
3. mass. Well, that's the tricky one. Saying that you define a kilogram as one bazillion silicium atoms is useless unless you can somehow actually produce a lump with that many atoms. As long as we can't actually be sure how many atoms are in there, it would be a useless standard.
These guys claim to have been able to do just that: say with a high degree of confidence that, yep, their spheres contain exactly that many atoms. If they're right, then we're finally ready to move the kilo to that standard.
A polar bear is a cartesian bear after a coordinate transform.
I think that Gravity Probe B has the most perfect spheres and they are much smaller that the Kilogram sphere.
Kilogram Silicon Spheres
"If you were to blow up our spheres to the size of the Earth, you would see a small ripple in the smoothness of about 12 to 15 mm, and a variation of only 3 to 5 metres in the roundness"
Gravity Probe B Spheres
http://www.nasa.gov/mission_pages/gpb/index.html
"If these ping pong-sized balls of fused quartz and silicon were the size of the Earth, the elevation of the entire surface would vary by no more than 12 feet"
We are Dead Stars looking back Up at the Sky
They should have visited this guy's website
http://www.kyokyo-u.ac.jp/youkyou/4/english4.htm?
making spherical mud balls. I've had this bookmarked in del.icio.us for a long time
Is this really the reason why it's a sphere? Crystals don't PRECISELY grow into a sphere do they? Won't they still need to shave or polish it to get it to the exact radius? And then they'll need to calculate the number of atoms using Pi, an irrational number!
Why don't they make it a cube and find a length that is close enough (cubed) to give them the approx. right number of atoms and then make THAT the standard? They'll then have an EXACT number of atoms making up each length. It should be easier to cut or shave off the requisite number of atoms to maintain it, a (perfectly) flat surface seems much easier to maintain than a 3D curved surface. In fact if they make it just a little too small they could probably even ADD to the cube in single atomic layers using vapor deposition!
Obviously brighter minds than mine have thought this through more thoroughly, so really, I'm curious: why is it a sphere?
By the way, maybe this is a good use for the ISS, to keep the 1kg reference MASS somewhere it won't be distorted by gravity, not kept at any particular country for measurement and you can keep it in a high quality vacuum for free! (A little expensive to get to though).
number of atoms = (volume * density) / mass of silicon atom
With the volume of a perfect sphere simply being
Pi*r^3 (I think)
It's also much much easier to test for the perfection of a sphere over any other geometric shape. All you do is spin it with slight axis rotation while a laser is pointed at it, and measure the distance.
Defective Logic
Its shrinking. Losing incredibly small pieces over long periods of times. No object can realistically stay -exactly- the same forever.
Not a dupe - a follow-up.
The first article mentions only the weight loss of the original kilogram, the second article follows up on that mentioning a perfect sphere is going to be made. The current article follows up on that, announcing the actual creation of this sphere.
Now the fourth article in this series should be the announcement of the number of silicon-28 atoms needed to create exactly one kilogram.
On the other hand, isn't the exact mass of atoms known? Then it should be easy to say "this number of atoms is exactly one kilogram". The creation of the sphere being an exercise left to the reader.
...has created the most perfect spheres ever made...
...roughly 9cm...
That precise eh?
That's actually the reasoning behind the Watt Balance another potential method for defining the kilogram.
Keep in mind that the Joule is a composite SI unit, and is itself dependent on the mass of the kilogram. Unless you can calibrate the energy measurements (exactly what they are trying to do) you end up with a circular definition.
Just define the KG in terms of pounds at 1 G. Do Americans have to solve all of France's problems for them?
I often don't like the choices people make, but I like the fact that people make choices. That's why I'm a conservative.
The answer is none.
None more round.
I think the reason why they made it a sphere is because a sphere is defined by one parameter only, its diameter. To make a perfect sphere all you need is to make sure it has exactly the same curvature everywhere. Now, let's see what it takes to make a perfect cube:
1) each of its six faces must be perfectly plane
2) each of its twelve edges must have exactly the same length
3) each of its twelve angles must be exactly ninety degrees
Just to illustrate how difficult this is, I once read this anecdote about Wernher von Braun: when going through his mechanical engineering course in Germany, one of the professors gave each student an irregular lump of iron. The assignment would be to create a cube, as perfect as possible, from that lump. The size of the resulting cube didn't matter but, naturally, if it was a very small cube it meant the student had a tough job getting it right.
Well, I mean from a purely physical point of view, the world is a lot more interesting (though sadly sometimes in a negative way, as you point out) because of physical differences. I find amusement in different breast shapes. I'm sure I'd be happy with one set of breasts attached to a special someone, but while I'm single I can honestly say that I quite enjoy the variety!
I'm sure you do love your wife's breasts, but that is presumably mostly because they are a part of your wife and you love her. They also are 'your' personal set of breasts so aesthetically you will also come to find them even more pleasing because of this.
People subconsciously come to prefer things that they own - they tested it on people with short term memory loss, getting them to rate some paintings on an aesthetic scale, then 'gave' them one of the paintings, came back later when the people had forgotten about the whole thing, and then asked them again to rate the paintings, and people rated the ones they were given as higher than before. I can't find a reference for this (I have a feeling it was in Robert Anton Wilson's Prometheus Rising but despite that being about the human brain I'm not sure how it fits into that context, so maybe I read it elsewhere), so take it with a pinch of salt if you will.
Personally I can vouch for that theory though, as I never used to find medium-smaller breasts interesting until I went out with someone who had fairly small breasts. Yes, she had a freakin awesome ass, but I learned to love her breasts too. I also tend to find women more attractive if I like their personality, and consider even good looking women to be 'ugly' overall if they are evil bitches.
which is totally what she said
It's 1024 grams, right? Easy definition.
(NSFW)
http://images.fok.nl/upload/050701_30560_howtodrawboobsfok.jpg
I am a physicist at the UK's National Physical Laboratory and I am involved in the redefinition of another unit - the unit of temperature. The work concerning the redefinition of the kilogram is >much more philosophically fraught and technically difficult. I understand many of the rather skeptical comments expressed here The current situation is unsatisfactory because the mass of the kilogram is changing, albeit by a small amount - a few micrograms in 1 kg - i.e. a few parts in 10^9. The aim of the work is to replace this artefact with (essentially) a procedure. Effort onne (using the silicon sphere) is essentially trying to build a link between a macroscopic mass, and the microscopic masses which we expect to be fixed. The other effort not mentioned here is called the watt balance which is a machine which can exhibit the same inertial mass as a kilogram - or any other weight. At the moment the two watt balances disagree with each other and they both disagree with the silicon sphere result. There is still a lot of work to do on both approaches. Incidentally, the reason is it is a sphere rather than a cube is because of edges. Edges are amazingly fragile, hence the sphere. ALl the best M
Problem being that if the balls were touching - well, it would be gay. Consequently, the answer is unimportant.