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Physicists Find More Precise Gravity Number
DM writes "Physicists establish the most precise measurement ever achieved of Isaac Newton's gravitational constant and use this information to recalculate the mass of the earth. Check out the article at ScienceDaily." Now if they could only recalibrate to make me really buff, that would be nice.
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CAIMLAS
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
I am very close to finalizing my anti-gravitation device and the only thing I needed to include in my source code was the exact definition of gravity. I should now be able to release (Open Source, of course) the code and agdk (anti-gravitation developer kit) in the next month or so. Here's some early demos
-- Stalkers Should be Shot in the Head
...42 by any chance? ;-)
Sorry, Emmett. They're scientists, not miracle workers.
Disclaimer: The opinions expressed are not necessarily my own, as I've not yet had my medication today.
Seems they tried this before, with a big failure:
;)
:)
""That is a huge embarrassment for modern physics, where we think we know everything so well and other constants are defined to many, many digits," Gundlach said. "
Hmm.. well it's great that they have recalculated Newton's Gravity Number, but.. in what will we gain with knowing the mass of Earth?
"Gundlach acknowledged that the more precise calculation probably won't mean much to the average person."
Ahh here we go.. not much to us, hrmm..
What will many different Earth Scientists/Chemists learn from this then? The article doesn't seem to mention anything.. Wow, we know the Earth's mass, lets move on to the next operation to waste money..
How really important is the value of 'G'?
If this is going to make teleportation devices and enhance lightspeed development, I'm all for it! I can't wait to teleport to China and back within seconds, wouldn't anyone love that?
""Gravity is the most important large-scale interaction in the universe, there's no doubt about it," Gundlach said. "It is largely responsible for the fate of the universe. Yet it is relatively little understood.""
What? I'm sure every student in every High School does *many* things concerning gravity, and different sorts of energy and how gravity affects them.. at least *I* did..
Gravity the most important part of this world? I thought it was evading black holes.. Oh wait, that does deal with gravity!
Ah well, anything new about our Earth to help to explain it is worth it to me. Good work Gundlach!
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A: I think it's a good idea.
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From the article:
... we are still running a number of tests in order to confirm our final number
... Earth".
The analysis of our first set of measurements gives us an uncertainty of only about 0.0015%
So it makes sense that they are not publishing the number until it is confirmed. But apparently they are sure enough about it in the sense that "[they] are already confident that [they] know the mass of
amnesty
...must be some heavy packets, eh?
I use Macs for work, Linux for education, and Windows for cardplaying.
Currently, G is defined as
6.67259 x 10 ^ -11 m^3/km/s^2
and the standard uncertaintity is
0.00085 x 10 ^ -11 m^3/kg/s^2
which is quite high when comparing to other fundamental consants
-- Note: These Comments are Generated by ME! Not You! ME!
9.8 m/s^2 = acceleration in earth's gravitational field (near earth). Certainly, this is rough, as it changes depending on your distance from earth (unless I'm totally screwed up).
What they are referring to here is the gravitational constant, used to calculate the force of attraction between two masses.
"Either way, that's about 1 trillion metric tons for each person on Earth. Put another way, 1 trillion metric tons is thought to be the total
weight of all plant and animal life on the Earth's surface."
I call all the plant & animal life!!!!! (I know, I know, I'm gonna have to pay somebody rent, sigh).
And I was just about to use this 16,000,000 mile lever to move the world and NOW its 20 feet to short... damn scientists!
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I'm a 4th Year Honours Physics Major who did something similar and did a lot of research into this so I know something about this.
As the article said, G is very vague in its defination. Some new calculations have acutally put G at 6.64x10^-11 to 6.69x10^-11 which is quite a huge range. Whereas the two other constants, h [planck's contant] and c [speed of light in vaccum] is more well defined and had gotten more accurate.
The biggest problem with measuring big G [what we are discussion here, instead of little g which is 9.81m/s^2] is the influence of other objects. We did the experiement for our class in a basement labratory and I was able to predict based on minute changes in the data I was getting that people were moving their desks around. I was 4 floors down from the top floor and when I went upstairs, the professor [I was able to predict where in the building from the measurements and the fact that he was the only one up there in that section] admitted he was moving around to re-orient his new desk.
Also, another time, a huge pickup truck came to the parking lot in front of the physics building. I noticed right away my measurements go askew cause of it.
As I said, G is very sensitve to tiny changes in the enviorment, much more then h [planck's constant] and c [speed of light]. Often, to measure the constant G, people has to work when there is no activity going [either at night] or somewhere remote. In fact, one of the recent measurements was taken in the middle of the Nevada Desert.
-- Note: These Comments are Generated by ME! Not You! ME!
9.8m/s^2 is g
G is 6.67259x10-11
-- Note: These Comments are Generated by ME! Not You! ME!
Here is another article from Discovery. A little more info, but not much.
If the earth is about .008 sextillion metric tons lighter than we thought it was, the sun won't be able to hold us, and we'll go spinning off into the coldness of space.
WHY, oh WHY, couldn't they have left well enough alone?
"The map calling the territory black."
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It was suggested that life in the Universe may take on many different forms and shapes. There are theories (hypotheses) of having life on neutron stars (the left overs of the star cores that collapsed on itself to produce a remnant size of earth and mass of 2-3 Suns that due to its huge mass and small size spins at almost the speed of light.) Life on such an object would not be supported by chemical reactions since no molecules not even atoms can withstand enormous temperatures produced on the neutrino stars. Still, we should not lose all hope, for life based on strong forces remains conceivable there.
:)
Strong forces hold together the nuclei of all atoms more complex than hydrogen. Suppose a proton some 10^-13cm in size travelling at speed of 1000kilometers per second (average speed for a proton) at temperature of 1million K. It would cover a distance of 2 meters in 10^-21 of a second. Human would cover this distance in about a second. So for a proton 10^-21 second means the same as 1 second for a human.
Collisions of many elementary particles on a neutron star could produce massive nuclei, each made of thousands and tens of thousands, of elementary particles. They would last for 10^-15 of a second and then decay. In other words, a massive nucleus might have a million different collisions or other interactions before it decayed.
So if these particles could produce some equivalent of a structure capable of storing information and of replication by selective copying (like the DNA or RNA) star might produce forms of life. Individuals that interact with their environment and with other individuals in an organized way.
If this really happened, the development of life would happen much faster than what we observe in our solar system.. 10^-21 second is one billion-billionth of the thousandth of a second then the origin of life would require not about 1 billion years (our planet: ~600million years) but about 1/billionth of a year, of 1/13 of a second! It may seem short to us but it might exist on the surface of a neutron star. (too bad we could not interact with them)
On the other extreme end of this is the type of life we could call a "Gravitational Life" based on Gravitational forces. A typical subunit of life would be so large that gravity would be the dominant force for it, not electromagnetic force, a star would work in this case as a base unit. Individual stars would play the role of atoms (or molecules) on Earth. An organism so large that its basic building units are stars and galaxies (maybe even multiple universes) could in principle be possible. Would you like to think about yourself as of basicly microorganisms living in a huge super organism? Of-course star and galaxy interactions are upon scale of millionth of years, so if life originated from repeated effects of such interactions (like molecule interactions) then there is a long way to go before a living organism based on this interactions could develop.
And you think the mass of earth is important
You can't handle the truth.
JESUS CHRIST!!! WHAT IS WRONG WITH YOU?
Gravity, or big G is constant everywhere, its used in a formula (that I cannot remember) to calculate the gravitational force between any two objects (along with there mass and distance (increases with mass, decreases with distance).
You aren't being pulled toward the center of earth, you are being pulled toward every particle in it. The average vector points to the earth's center of gravity. When you get closer to that point, more and more of the vectors would be pointing away from that. When you got to the center, the average vector would be (0,0,0), so it would seem that you were weightless. When you get farther away from earth, the distance to those particles would be less, so the effect of gravity would seem to be less. That's why don't fall into the sun (since it has more mass then earth)
Its one thing to be misinformed, like the author of the root comment. It's quite another thing to be wrong and insult people who are correct. The second thing makes you an idiot.
ReadThe ReflectionEngine, a cyberpunk style n
This of course has had it's ramifications in the modern view of the Universe. See this Slashdot Story, and the recent developments which suggest that is it "flat".
What I say is, this is a good start, but we have a long way to go.
AND, does this also include the all ellusive, but ever present Dark Matter in the calculation?
It's 95% of the universe, you know....
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"Geeks, Where would you be without them?"
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...or a solution waiting for a problem. Has anybody come up with any good applications yet? How expensive is this device? Could you use it to find, oh... trapped miners, people burried under earthquake debris, or gold veins? I mean, if you can tell that your professor is moving around upstairs, then you can presumeably tell that there is a tiger behind door number 2, but could it be made more precise and/or accurate than other techniques (e.g., ultrasound, cat scans, etc.).
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
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In principle I don't see a problem with this - my personal belief on the subject is that life *could* form wherever there is a system of sufficient complexity, no matter the exact details of that system. So if you had enough "macroatoms" or whatever, the gravitational force could cause this to happen.
But the real killer is the timescale. Bearing in mind how many times smaller than the electrmagnetic force gravity is, the timescale would be correspondingly larger - rather than a ~10^9 second lifespan like we have, an equivalent gravitational being's lifespan would be ~10^49 seconds long, but for it, that time would seem the same length as a human lifespan.
In that length of time, the structure of the Universe will change. Spacetime will expand, leading to increased delays for communication between different components of the entity, stars will die, galaxies will collide, black holes will form and entropy in general will increase. The lifespan of this entity would be so great that by the time it could have formed, either all protons in the Universe will have decayed, all matter will be in slowly evaporating black holes, or we'll have had the Big Crunch.
So I think it's possible in principal, but not in practice. Of course, I could be totally wrong here :)
5.972 sextillions? What the hell is that? Oh, you mean 5.972 x 10^18. Is this mag for scientists or what?
Also, did I miss it or did they not tell us the new value? Yesterday, GPS is opened up to civilians, but today G becomes proprietary information. One step forward...
You give a very self-centred view of science.
You are right, if you know surface gravity and the mass of the planet then you can get around G. But wait -- we didn't know the mass of Earth correctly. If you read the article, as a result of finding the more accurate G now we have a different number for the mass of Earth. So how is it that G is unimportant?
In close orbit perhaps the significance of these numbers is smaller, but in geosynchronous orbits where the satellite has to be locked into place 4.215x10^7 m away you'd better be sure that your numbers are right so that you're not just throwing billions of dollars randomly into space.
We can't find the mass/density of planets and stars without G. We have to throw something into orbit above it. If we don't even know mass + density then it's obvious we can't use Mass + surface gravity to do calculations. The other way is to go on the surface and measure acceleration, but good luck on planets like Venus with acid rain up the wazoo.
There's already been a very good book written on this called the Dragon's Egg by Robert Forward. A manned mission is sent to a drifting neutron star that passes near the solar system. The natives evolve from 'plants' to an intelligent species in the time the mission takes to reach the star and they go from 'stone age' sun worshipers to space travelers more advanced then us in a matter of days. Communication is established with a gamma ray based mapping device that some of the natives can see.
Proton is 10^-13 centimeter in size, and speed of 1000 kilometers per second is typical of protons at temperature of 1 million K would travel a distance of 170centimeters in 10^-21second (one billion-trillionth of a second)
"The Search For Life In The Universe" 2nd ed. by Donald Goldsmith & Tobias Owen, chapter: "How Strange Can Life Be?" pp 242/244
Enjoy
You can't handle the truth.