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NASA Probe Validates Einstein Within 1%
An anonymous reader writes "Gravity Probe B uses four ultra-precise gyroscopes to measure two effects of Einstein's general relativity theory — the geodetic effect and frame dragging. According to the mission's principal investigator, the data from Gravity Probe B's gyroscopes confirm the Einstein theory's value for the geodetic effect to better than 1%. In a common analogy, the geodetic effect is similar to the shape of the dip created when the ball is placed on to a rubber sheet. If the ball is then rotated, it will start to drag the rubber sheet around with it. In a similar way, the Earth drags local space and time around with it — ever so slightly — as it rotates. Over time, these effects cause the angle of spin of the satellite's gyroscopes to shift by tiny amounts." The investigators will be doing further data analysis over the coming months and expect to release final results late this year.
That project took way too long. I remember people working on it when I went through Stanford in the mid-1980s. It was something of a boondoggle; it mostly produced students, not flight hardware. I'm glad to hear it finally worked, though.
... balls on rubber sheets. Seriously.
True, it did take a while. But I'd like to think it was worth the wait. Also, for those who care, here is a link to the Stanford page http://einstein.stanford.edu/ it has the same info as the article along with more stuff about the project.
Actually people have been preparing this experiment since the 1960s.
There was a great lecture about this on this year's hungarian skeptics conference, spiced with the real life experience that Hungary was part of the soviet influence sphere at that time, so when one physicist was allowed to go to the USA for a year to do research. When he came back, his colleagues were flocking him, discussing the news and that the americans are setting up this experiment. The lecturer, now an old man, can finally see the result of the experiment they were discussing more than 40 years ago.
It takes a man to suffer ignorance and smile
Be yourself no matter what they say
Thomas Edison said that genius is 1% and perspiration is 99%. It's nice to see scientists proving him right.
I spent a week watching all the Nova PBS episodes, learning about this and string theory. Even though I'm not a mathematician or physicist, it certainly caught my attention.
http://www.pbs.org/wgbh/nova/elegant/
"To be is to do." -Socrates
"To do is to be." -Jean-Paul Sartre
"Do-be-do-be-do." -Frank Sinatra
If I put three gyroscopes, each spinning in a different axis at right angles to each other, into a box, wouldn't its increased inertia make it just seem more massive? How does the momentum of all those electrons and other subatomic particles spinning around contribute to its apparent mass?
--
make install -not war
This was not a NASA experiment per se, it was a Stanford experiment. The original press release can be found here. The official stanford website also lists preliminary findings here.
This seems like a waste of money and resources. As any creationist will stress to you - gravity is only a THEORY.
Let me see if I understand you: is this similar to the mall thing where you throw coins into it and they go round-and-round until disappearing into the hole below? If it is, then...I...waitaminit...we're all going to die!
Genius is one percent inspiration and ninety-nine percent perspiration. -- Thomas Alva Edison
sciency details:
d _einstein_iv_showdown_in.php (April 4)
http://cosmicvariance.com/2007/04/15/dragging-on/ (4:33 p.m.)
Also of interest if you're into this sort of thing, what Beyond Einstein programs will be cut?
http://scienceblogs.com/catdynamics/2007/04/beyon
sad if you compare sticker prices to the $10 billion per month on the Iraq adventure.
If you need text styles to communicate then you don't have a message.
with regard to this. This isn't someone claiming ID causes the universe to act as it does, this is FSCKING Einstein. That he is proved correct is more about man understanding the universe, and relying less on the theory that it is too complicated to understand and must have been created by an imaginary being. This *IS* news, and should be heralded appropriately.
While some might think me a troll, think about it, Einstein was right. That means that we are that much closer to understanding how the universe works. Even 100 years ago such progression could only be imagined, not proven. In the time that we live in, science books have to be revised every year not because of a need to spend government money, but to actually keep them up to date!
So much change and investigation. People have become numb to the actual changes.
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I assume this is the project: http://en.wikipedia.org/wiki/Gravity_Probe_B
g ravity_probe_b.jpg
And the probe itself is just astounding: http://en.wikipedia.org/wiki/Image:Einstein_gyro_
Gotta love xkcd : )
http://www.xkcd.com/c54.html
It's worse than that. If GR is right and not just the observable result of some underlying process then we live in a block universe. That not only means that QM is wrong, it means we have no free will.
I like what you have to say about every moving object emitting Hawking radiation.. kinda reminds me of Mach's Principle. Perhaps every object in the universe emits particles in sympathy to a moving object.
How we know is more important than what we know.
The thing is that this effect has been tested at strong gravity. There is no dispute that GR is not correct in the strong gravity limit. The strength of GR is only disputed at weak gravity, or near Planck's length. It is a good verification of GR, but I don't think anybody thought that it will not be vindicated.
We need a probe to test GR at L1 point if the gravity there is significantly weaker than a0 to distinguish between MOND and DM. This IMHO is the most important test. If it is not possible to test MOND at L1 point, because the MONDian bubble is too small then there is no hope for a test within the next decade. Because that is how much time a very modern satellite will take to reach beyond the solar system where the gravity is significantly weaker than a0.
Politicians and Pedophiles: Two groups of exploitive bastards who are most dangerous when they're thinking of children.
Jeez, 19551960, it doesn't take Einstein to figure that one out.
Firstly, I'm going to guess that frame dragging is verified at no better resolution than the curvature of space/time, but that as far as they can tell, it exists and meets the values expected by Einstein.
Frame dragging is the name of one particular way in which spacetime curves. It is curvature. To say something about frame dragging or curvature is to say something about the other. I don't know if the parent statement makes sense or not. The group has not released their frame dragging measurements yet, just the geodetic precession measurements (the precision of which will likely go up as they isolate more systematics in their data as they move toward making a statement about frame dragging). Frame dragging is about 100 times harder to measure than geodetic precession, for the mass and spin of the Earth.
Secondly, I'm also going to guess that QM experts will start to get a little nervous. The properties any future QM model of gravity must have contradict the GR model. They cannot both be right. The more "right" the GR model, the more problematic a QM model. This doesn't mean a QM model does not exist, only that it is most undesirable (from a QM perspective) for the GR model to make highly precise and accurate predictions.
GR is arguably the most successful physical theory to date (I would say that electrodynamics rivals it since it has been formulated classically in curved spacetime and also has been quantized successfully in flat spacetime, but that is another discussion). Newton was not "right", but note that GR simplifies to Newtonian mechanics in the weak field and non-relativistic limit. Any theory which supersedes a highly successful physical theory must reproduce said theory in the proper limits. A quantum theory of gravity must reproduce GR in the macroscopic limit, just as quantum mechanics has a correspondence principle which allows it to reproduce classical wave and particle phenomena in the appropriate limit. I don't think any physicist is nervous about these results - everybody expects GPB to verify the predicted frame dragging. Deviations from the values predicted would excite fans of MoND, SVT theories, and other alternative theories of gravity.
Thirdly, frame-dragging occurs at a non-zero distance from an object.
Frame dragging curves spacetime globally, but falls off to asymptotic flatness. The parent statement probably makes sense.
This doesn't matter, for the purpose of these observations, as they're nowhere near accurate to measure the relativistic effects that apply to the information passed that creates the effects in the first place. Nonetheless, such an affect must exist, or you'd end up with infinitely fast rates of change of state, which is expressly forbidden in GR.
The NSF and NASA don't spend this much money to throw an instrument into space unless they think it will actually measure what it's supposed to. The gyros are the most spherical macroscopic manmade objects, which used superconducting quantum interference devices (SQUIDs) to precisely measure their precession, blah blah blah, read about it on their web site. I sure hope they're accurate enough to measure those relativistic effects, because that's exactly what they've been designed to do. I don't know what information you are talking about. The Einstein Field Equations are local, so there is an inherent limit on the speed at which 'information' (curvature) propogates through spacetime.
It's a gross simplification and it's not an "obvious" conclusion to reach by any means, but if the curvature (and restoration) of space/time has nothing analogous to Hooke's Constant, then after a gravitationally massive object has move
-Leo
Oh for the good old days when Gravity was a Downer, Friction was a Drag, and physics could be understood without needing about three lifetimes worth of math degrees.
When our name is on the back of your car, we're behind you all the way!
Glad it worked? I'm horrified it worked. /. geek wouldn't know the term) than we thought we were before.
Every time someone (re)validates Einstein relativity theories, we actually know we're one step further from FTL (Faster than light - though I'd be surprised if any
Damm gravity.
When in danger or in doubt, run in circles, scream and shout [Robert Heinlein]
FTL? WTF? Everybody knows that FTL drives are a work of fiction.
No, my friend, what you need is a warp drive.
For some reason the article and summary only mention that Gravity Probe B was trying to measure was "minuscule" however, I at least find the actual quantity to be FAR more impressive than some journalist calling it small. Anyway want to know the precession?
Frame Dragging Effect (has NEVER before been measured): 1.1x10^-5 degrees per YEAR
Geodetic Effect: 1.8x10^-3 degrees per YEAR
Clearly then, these were not merely "minuscule" shifts...the potential for error is great.
More information can be found at http://www.nasa.gov/mission_pages/gpb/index.html
This may almost sound Trollish, but I am by no mean a Physics major, and it shows in this.
Could anyone who actually is familiar with this overall project (Not a stats person, I'm sure they'll say it's insignificant) tell us if the margin of error is truly acceptable?
I understand that there is always a margin of error due to minimum measurable differences, but can physicists now go "Phew, we are now FULLY sure this is right, and not that there has been a measuring fluke" or is there still some doubt? I mean, it seems close, but one can never be sure in physics as to how closely it *has* to line up.
jmp
This means that there are no differences between GR and MOND in the gravitational limit that this test has been conducted. This means that MOND will have the same problem that GR has, if the tests don't come out as predicted. I guess in this case the tests will be considered to be faulty, as there are literally no theories (that are not considered crackpot) that give different results different from GR in the strong field regime. So the tests by Gravity Probe B will not make any difference, though it probably will give GR theorists something more to brag about.
There is a big misconception about MOND, that it is a theory. It is not, it is a law that works very well at the Galactic Level and somewhat at the cluster level. MOND fits all galactic level data to the limit of their expected accuracy. This it does so with a single universal constant. But nobody knows why it works so well.
As such it is very obvious there is something behind MOND. GR cannot explain MOND without fine tuning DM in such a way to give rise to MOND. But since MOND uses only Baryonic matter, it leaves DM with no degrees of freedom, which is not possible, so DM must not exist at the Galactic level.
At Cluster level situation is different MOND does not match up with the missing mass. Which means either there is Dark Matter at the Cluster level or MOND itself is a reasonable approximation of the correct theory of gravity only in the galactic limit. Beyond the galactic level it ceases to be a good approximation.
If there is dark matter at the cluster level then there must be a reason why it does not exhibit itself at galactic levels. This would meant that the dark matter is hot and moving at a high velocity, which allows it to form stable structure only at the cluster scales.
The interesting thing about the universal constant (a0) of MOND, is that if a particle is accelerated by a0 for the whole life of universe then we will get the speed of light. This would seem to provide a hint that a0 is due to the curvature of the universe.
This actually solves a problem in GR. If GR is absolutely correct then the curvature of the universe cannot be determined, which is also called the flatness problem. This problem is currently avoided by assuming that there was an inflationary era when the universe expanded so much that we only see a very small part of the universe which is flat. So that GR equations are correct. But if that is not true and the universe is not really that big then GR will break down because of no fault of itself, but simply because of the curvature of the universe.
So in my opinion GR is correct but the curvature modifies GR in such a way that we observe MOND.
because nobody was waiting for the result? Any doubt concerning the theory will focus on other areas.
Actually, considering that Edison is famous for:
- taking credit for his employees' inventions as if he personally and singlehandedly came up with them. (There are at least 28 inventors that Edison ripped off this way, including for example taking credit for inventing the motion picture camera. Actually, it was invented by W.K. Dickson.)
- patented stuff he didn't actually have yet, and/or wasn't even original
E.g., he applied for a lightbulb patent a full year before actually having a filament that was commercially viable: and Edison's, or shall we say, his teams, _only_ contribution there was a commercially viable filament. The light bulb as such had already been discovered, it just didn't last long enough to be worth buying. But wait, even the carbon filament wasn't new: Edison't patent application itself had come a whole 1 year after Joseph Swan had patented a working model in England (and was working at it since 1850, 28 years earlier). So basically it took Edison and his team two years to copycat someone else's invention and claim credit.
- bogus patents, e.g., a number of patents on ornamental designs
- using PR and bad science to win public support: see the "war of the currents", where Edison (who wanted to sell direct current) paid people to roam the country and conduct demonstrations of killing cats, dogs, and once even an elephant with alternating current. Just, you know, to show people that alternating current kills. (While supposedly his direct current at the same 110V doesn't. Yeah, right.) He's also the author of the electric chair, as part of the same campaign to prove that AC kills. The first execution had the guy pretty much fried alive over a time of more than a minute (he certainly was still alive and struggling after the first 17 second jolt), in a show that sickened spectators and was described by the New York Times as, "an awful spectacle, far worse than hanging." That's the kind of PR that served Edison's purposes.
- shafting the employees. E.g., Tesla was promised a (huge for that time) bonus of $50,000 if he succeeds in making an improvement to the DC generators. When he actually succeeded, Edison didn't pay him, and in fact told him, "When you become a full-fledged American you will appreciate an American joke." In fact, he even refused to at least give Tesla a raise.
- mis-treating his employees. They actually spread word of Edison's current mood, so they'd know to duck for cover if he's in a bad mood.
- speaking of Tesla, here's one thing he said about Edison's dumb trial-and-error methods, a.k.a., 99% perspiration: "His method was inefficient in the extreme, for an immense ground had to be covered to get anything at all unless blind chance intervened and, at first, I was almost a sorry witness of his doings, knowing that just a little theory and calculation would have saved him 90 percent of the labor. But he had a veritable contempt for book learning and mathematical knowledge, trusting himself entirely to his inventor's instinct and practical American sense." (Would explain why most "Edison" inventions were actually from employees who actually understood what they're doing.)
- various attempts at monopoly, including the infamous "Motion Picture Patents Company", a.k.a., the Edison Trust. You know, if you thought that MPAA is bad, the MPPC meant you couldn't even make independent films without Edison's blessing.
- showing more contempt to the artists than the RIAA today, and in fact, enough to make the RIAA look like the good guys. Edison refused to even print the artist's name on the label. You're buying Edison music, you peon, not some artist's music. On one occasion he stated, "I would rather quit the business than be a party to the boasting up of undeserved reputations." Yeah, who do you think you _are_ to be getting any reputation for your talent and popularity. Only the great Edison should get a reputation out of it.
- letting his personal moods and preferences be the only criterio
A polar bear is a cartesian bear after a coordinate transform.
I don't think anyone's concerned about proving Einstein absolutely right or absolutely wrong—if you look at it in those terms, any theory is bound to be proved "wrong," eventually, in that it'll fail for some ever-increasing standard of precision. What's news here is that we can now trust Einstein's equations to predict our measured reality within that cited "1%," confirming that general relativity is a pretty damn useful model. But that doesn't mean it won't be supplanted next year by something even more useful.
Make Slashdot readable! See journal.
Somebody please mod this up funny
dumbass
Basically, the mission hasn't yet succeeded, and it doesn't seem to be completely certain that it will.
/ ExperimentError.pdf) has a one-sigma error of 100 milli-arcseconds per year, significantly larger than the relativistic effect and significantly larger than the effect from the motion of the target star through space. The initial expectation was for an error budget of less than 0.5 mas per year, so there was a lot of work done on measuring the proper motion of the star to that precision.
The goal was to measure the frame-dragging effect of the Earth, which is of the order of 40 milli-arcseconds per year; the current calibration (http://einstein.stanford.edu/content/aps_posters
The problems turn out to be really crazily subtle issues in solid-state physics -- the deposited metal films on the gyroscope and on its housing retain charge in patches large enough that they have to be modelled rather than averaged out -- plus an annoying issue from classical mechanics where the motion of a rigid body around three axes XYZ depends on the ratio of the differences of the moments of inertia X-Z and Y-Z. Whilst the gyroscopes are absurdly precisely made, so the moments of inertia are very close, the ratio of the differences of the moments of inertia is a macroscopic number; this is the same effect, and even a similar cause, to some of the oddities with low-precision floating-point arithmetic.
They'll probably be sorted out, sigma might be reduced by a factor ten after another year's modelling effort, but it seems unlikely that they'll get it down by the factor 200 they were hoping for.
The frame-dragging has already been measured indirectly by looking at the flickers of X-ray sources caused by frame-dragging-induced precession of the accretion discs around black holes, and most of the theories that suggest relativity is wrong would suggest that any oddities would be more pronounced in the huge gravitomagnetic fields near black holes than in the tiny fields near a mass as small, as non-dense and as slowly rotating as Earth.
It's the 2nd amendment, dumbass. Are we a little dyslexic.
Wormholes count for something don't they? ...now all we need to do is harness the power of the sun...
Who moded this person a troll, without posting a response? Everything they said went about a mile over my head, and I consider myself somewhat informed about this subject. Just because you don't understand the post, doesn't make it a troll.
This is funny, and not just because the only person I know with a tattoo on her lower back is an ex of mine.
Earn a % of cash back from Newegg, Tiger Direct, Walmart.com, and more: http://www.mrrebates.com?refid=458505
WTF?
cough... ...hence being within 1% of the predicted results, indicates the predictions made decades earlier were probably pretty spot on!
The test results have a significant margin of error...
cough...
ie. 1% probably in test results (which someone up the screen noted are not yet fully processed) rather than in the theory...
Worth considering before throwing out a theory that matches test results to within 1%, wouldn't you say?
thx e
Sorry, somehow didn't see the other responses. I guess this discussion is way over my head, I'll just go to bed now.
Boss, I was late to work this morning because of frame dragging. I would have been here earlier if spacetime hadn't been warped and then twisted by my car.
Peter
Downsize DC Today!
Can someone explain to us layman, how being within 1% of a prediction is impressive for this particular area? (For example, if newtonian physics only provided 99% accuracy for localalized physics on earth, it would be a joke.) I'm sure this "within 1%" is impressive, if the experts in the field are saying so; but explain to us layman, why?
Love many, trust a few, do harm to none.
It's an approximation, like most mathematical equations in physics. The fact that it measures something so esoteric within 1% is monumental. First, it proves that Einstein's theories were "correct" in their premise that this effect exists at all, and second, his theories approximate the effect within 1%.
Looking at it with hindsight, it's not too difficult to see that this probably is the way it should be, but for Einstein to have come up with it in an effectively hostile environment is truly a measure of his greatness that should not be understated. It was a leap of insight in a direction everyone else wouldn't even consider.
The cesspool just got a check and balance.
Warp drives are so 1960's you need either slipstream or even better.
An oscillation overdrive. That would be exactly what you need.
Now to find that rock and roll physicist that has the prototype.
Do not look at laser with remaining good eye.
I'm just a student, but here's what I gather:
MOND is, as its name implies, a Newtonian theory of gravity, which means it predicts no frame dragging at all. As such, this experiments shows it to be incorrect, just like Newtonian gravity. This is expected.
What it would affect is alternate theories of gravity that are equivalent to general relativity but reduce to MOND instead of Newtonian gravity in the non-relativistic limit. I understand TeVeS is one such theory, but I don't know what its predictions of frame dragging are.
Then why don't they take the same experiment and plop it in orbit around Jupiter? that gravity well is exponentially larger and therefore should have the same effect on the measurements.
Do not look at laser with remaining good eye.
Validated to 1% is validated to 1%. Welcome to how science works. Pretty much every single theory out there is validated to some percentage, limited by the presicion of our measurements.
That is all science except climatology, Global warming is validated to 100% fact!
An experiment only validates or invalidates a single hypothesis. The results will only create more hypotheses to test. The second you begin to believe you know exactly how and why something happens you begin to err and surely nature will find a way to make an ass out of you.
I guess my answer to your question is nothing is ever sure nor can it ever be.
You're nothing; like me.
Nice little strawman you've got there. What are you going to do with him?
What, the Stargates aren't good enough for you?
Bingo !
I was going to post this myself. The goal was to measure frame dragging. The geodetic effect has been measured before (LLR and binary pulsars),
and is not nearly as interesting (i.e., its hard
to see why you wouldn't have it). It's the frame dragging that motivated the decades of effort and expenditure.
If they can't do frame dragging, the experiment will be deemed a failure.
naw, a Bergenholm is what you need
Ptolemy said the planets circled the Earth in epicycles, and mathematically "proved" it to the accuracy of available instruments. This was good enough for about a 1000 years. Together, Newton and Galileo proved heliocentricity, but calculated ellipitical orbits, also wrong, and also within the accuracy of available instruments. Brahe and others eventually measured things so precisely that they were able to find that Newton had an error, but they didn't understand it. Later, someone (I forget who) was able to measure the orbit of Jupiter's (known) moons and show that the speed of light caused an apparent lag in their orbital motions. But planetary orbits still didn't obey Newton precisely.
The world had to wait for Einstein to get an explanation - space/time curvature, etc, predicted the variance from Newton's calculations.
Somewhere in all of this, British scientists predicted the existence of Australia by the wobble it causes in Earth's spin.
Failure of real world measurements to match theoretical predictions can lead to greater discoveries. Sometimes the failure is more significant than success would be.
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
http://en.wikipedia.org/wiki/Zeno's_paradox
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
You have it wrong my friend. Less guns just means that the one who does have one is more powerful than the disarmed general populace.
Generally speaking, a society that has them everyplace is going to be far more democratic than one where only the ruler has one, and it doesn't make an anorexic rats ass difference whether that ruler started out as a saint, or a thug. The existence of a ruling class with guns to enforce their rule, will in time convert that saint to a thug simply because even the saint will want to impose his saintly ways on the masses. Not to mention he gets used to the ruling privileges and will use that weapon to maintain that privileges perceived benefit, like eating a little higher on the hog, being driven around in $200k vehicles etc etc.
I'm reminded of the phrase about 2 wolves and a sheep discussing lunch. Its only democratic if the sheep is better armed than the wolves.
The armed society is also a more polite society. Carrying, as the phrase is used, means I'm more polite to you simply because being impolite might cause me to discover I'm not the only one carrying. That's a far more governing factor in ones actions than the possibility of my walking into a situation at the local 7/11 that requires it come out in an attempt to salvage the lives of those being threatened.
Putting that into the perspective, had I been one of those students at VT, you can bet the farm that my undercover would have spoken at least 4 times in defense of my fellow students. Its not a matter of what I might do being right or wrong, and I might still have been killed because I was underarmed, but at least I would have had the tool to argue the point.
But I am not a student at VT, and its about 50 years too late to be one and have any expectation of it being a profitable endeavor to me, so the point as to what I might have done is moot. IMNSHO, school enforced rules that prevent any effective means of self-defense in such a situation only serve to contribute to the carnage and the enforcers of such rules should be both prosecuted and removed from positions of power before they do any more damage.
So while my deepest sympathies are with the families of the victims, my outrage is with the gun control advocates whose effects on society in general made that situation possible in the first place. We should prosecute these jerks as accessories every single time an incident like this occurs, because its their efforts to disarm the general populace that make it possible for scenes like this to develop on the scale that it has in the last 40 years.
--
No Cheers today, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
After they got rid of capital punishment, they had to hang twice
as many people as before.
When are they going to validate Newton's laws of physics? Einstein Einstein Einstein is all we ever hear about these days, isn't it?
Consider yourself spoken to.
You can drive a truck through a hole that big.
There's obviously nothing wrong with the model, but people tend to forget that multiple models can exist (and be applicable) simultaneously.
Not a single scientist is forgetting that. Why are you accusing them of this?
FTL? That what the waist band on my underwear says.
1) your sig has a very lame typo 2) take comfort in the 1%.
First we had the deistic theory of physics - things fall because they fall, big guys hit harder because they're big, and so on.
Then we moved up to Newtonian physics.
Then Einsteinian.
Who's next? Bohr? Someone I've never heard of? Who knows, but it's an interesting question.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
This was intended to be funny, but Ill take troll. :)
To those claiming it to be a straw man, it is not! I see people in here backing scientific method that in global warming threads claim it to be a proven fact. You can not have both! So when people ask why it is 99% and not 100%, maybe we should look at the myths that are put forward as science and stop pushing the myths.
During the 40 years it took to implement this experiment several other observations of interplanetary probes already proved it.
Jargon/Bogon Filter output to console:
"Even though this test is not being done on Earth, it is still being done pretty far down a deep gravity well. It might be interesting to repeat this test at the Lagrange point between the Earth and sun (L1). The only other choice to find flat space is to shoot the sucker out of the solar system, which would take too long."
Some mornings it's hardly worth chewing through the restraints to get out of bed.
>Who moded this person a troll, without posting a response?
You can't mod and post. One or the other, but not both.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
I am more and more impressed with Einstein every time something like this happens. To be able to sit in your house, thinking about the way the universe works, without a single real "test" to validate what you think, not even considering how science fiction off the way things like General Relativity is, bending space time fabric etc... That is just amazing to have it all proven "correct" a hundred years later.
Now the question will be, can we prove if String Theory is in fact correct. Tiny strings, massive membranes, 11 dimensions... it's even more "crazy sci-fi", but the math is good and that'll be really amazing if we can test it.
There is a new particle accelerator being built (largest in the world), which will help us detect the escaping of gravitrons if they do really exist, which wont prove string theory, but get us one step closer.
Modesty is one of life's greatest attributes
(Not a physisist either -- for that matter, I didn't even get A's in physics) but weren't a majority of the advances in physics made by refining prior equations -- adding factors or constants -- so that it isn't really proving something wrong so much as it is clarifing something that has been (at the layman level, not the physics level) true enough.
Layne
I think the award for longest project ever should go to this project.
The Pitch Drop Experiment
I can't wait for the tenth drop! WooHoo!
I only look human.
My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
Please, nobody tell the autodynamics people about this -- they'll get really depressed.
You're close, but you've got your dates all mixed up (it isn't really a big deal, it is a very easy mistake to make, in fact you'll see it is actually kind of funny). I'll try to clarify things. Also I am not sure who you refer to when you say "Brahe" I thought you meant Tycho Brahe but he died (1601) before Newton.
First of all, planets don't strictly follow elliptical orbits; for example it has been shown that Mercury's orbit varies chaotically. On the other hand elliptical models are quite accurate.
1676 Ole Rømer makes a quantitative measurement of the speed of light by observing the moons of Jupiter, he concludes that the speed of light is finite. The story behind this is quite amusing, apparently it was possible for Ole to get the data he needed form the great Paris observatory because he was invited there by a man who found him quite attractive. Good ol' Ole published his findings in 1676 in the journal "Journal des sçavans"
1687 Isaac Newton publishes "Principa," his work on mechanics and gravitation. Ironically Rømer essentially killed Newtonian mechanics before Newton even published them. Clearly then, it was long known (at least by some) that Newtons laws of gravitation were wrong to begin with, however despite this they are still incredibly useful to this day and shockingly accurate.
1727 James Bradley measures stellar aberration, providing conclusive evidence supporting Rømer's idea that light propagates at a finite speed.
1846 Urbain Le Verrier's calculations contribute to the discovery of Neptune. I am not exactly sure when, but by around this time it is known, and has been shown, (in part by Verrier) that the perihelion precession of Mercury is not fully explained by Newton.
1916 Einstein publishes another paper on gravitation, he calls his new theory the general theory of relativity. One of the earliest tests of this new theory Einstein did himself. The test was to see if the theory could explain the perihelion precession of Mercury; it did, perfectly. Many more astonishing predictions arose out of GR. Among them gravitational lensing, gravitational waves, and black holes.
Thank you for the good post. I was tempted to reply, as I have recently begun studying QM and GR but so much of what he said made no sense at all to me that I didn't know what to say. For some reason I did get the sense that the QM nervousness he spoke of (which is ridiculous) had something to do with him thinking the measured precession comes into conflict with the uncertainty principle (or maybe he dislikes the precision of the predictions). Honestly this guy reminds me of some of the people in my classes, I try to discuss the QM we are studying with them and it becomes immediately clear to me that they have no idea what is going on, and they don't even have a solid understanding classical mechanics.
Al Gore is talking about General Relativity now?
Forgive me for being a college student, but the geodetic effect reminds me more of what happens to your forearm when you use it to open a beer bottle.
Miren al Pepino! Los vegetales invidian a su amigo, como él quieren bailar. Pepino Bailarín!
I was sure I'd get a lotta the details wrong. I didn't take time to look it up - I figgered wikipedia, etc is too easy, so the parent poster could look it up him/herself if interested. But thanx for the correction!
I was just showing how nitpicking the numbers can sometimes lead to new discoveries as well as confirming old theories.
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
It sure must be convenient, living in a black-and-white world like that. None of those annoying shades of grey that make everything so complicated for the rest of us.
So tell me, do you support private citizen's rights to own thermonuclear weapons?
This experiment for gravity wells could have been done in the comfort of your own home for musch less cost. Merely have the average person sit on one end of a 2 seat sofa. Next have a person weighing say.... 300lbs. sit on the other end of the sofa. The result is obvious, the the lower mass body will fall into the gravity well created by the larger mass body. Happens every time I go to my best friends house, I tend to fall into the gravity well he creates.
-Eric
Oh, agreed completely. If I seemed to be minimizing the importance of these results, or of Einstein's contributions to physics for that matter, I apologize—I probably could have written more clearly. These results are important because they confirm Einstein's model is a better description of our perceptions of reality. Should these perceptions grow more exact or change otherwise in the future, which doubtless they will, we'll need an updated model to account for the discrepancies.
In that light, Einstein didn't prove Newton wrong. Classical mechanics remains the most useful way for us to model many everyday phenomena. General relativity gives us a much more broadly applicable description of the universe, but if that fact alone makes Newton wrong, Einstein's going to be proven wrong too.
Make Slashdot readable! See journal.