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NASA Gravity Probe Confirms Two Einstein Predictions
sanzibar writes "After 52 years of conceiving, testing and waiting, marked by scientific advances and disappointments, one of Stanford's and NASA's longest-running projects comes to a close with a greater understanding of the universe. Stanford and NASA researchers have confirmed two predictions of Albert Einstein's general theory of relativity, concluding one of the space agency's longest-running projects. Known as Gravity Probe B, the experiment used four ultra-precise gyroscopes housed in a satellite to measure two aspects of Einstein's theory about gravity. The first is the geodetic effect, or the warping of space and time around a gravitational body. The second is frame-dragging, which is the amount a spinning object pulls space and time with it as it rotates."
Please, can somebody restore the fortune database? Thanks.
Uh, and First Post.
But you can confirm predictions....
But you can confirm predictions. RTFS.
Note that the posted description makes no mention of proving anything, unlike the original submission... Confirming just means that further evidence was in line with expectations; not conclusive by any means. It's always good to hear that our understanding of physics is sound, even if new mysteries are more exciting!
It doesn't state the theory has been confirmed, it says two of the predictions made by the theory has been confirmed.
You can't confirm or prove theories, you can only gather supporting evidence or disprove a theory.
Why, if you disprove the theory "A is so and so" you have just proven the theory "A is *not* so and so"!
Uh oh.
Looks like someone didn't account for gravitational time dilation.
"Imagine the Earth as if it were immersed in honey," Francis Everitt, GP-B principal investigator at Stanford University in Palo Alto, Calif., said in a statement
Doh, this is Slashdot, we want a car analogy, please. And have the numerical results expressed in libraries of congress per football field. Thanks.
No, you have only proven that "A is not *neccesarily* so and so".
OK, geodetic effect, check. Frame-dragging, check. Commence dev. project warp drives
I am not an American, but I have seen both the blue pearl image and the pale blue dot image. I have read about how long these projects have run and the astounding quality of the instruments that must be on satellites like these along with the massive foresight it must have taken at launch time to make them relevant decades later. You can criticize the USA all you want for their wars, and I have heard some harsh criticism of NASA too but the most astounding images and discoveries have always come from the here because they are on the pinnacle of space exploration. The world would be a lot less interesting if it wasn't for them.
why the fuck is this called get more comments? i'm guessing it actually refreshes for new comments, i was thinking it actually showed more of the truncated comments for this story like it does on every other fucking site.
This is a joke. I am joking. Joke joke joke.
Have you seen the comments in TFA by this David de Hilster guy? What a fruitloop. Check out his picture. Want some love particles, baby?
good article, hopefully useful to all go like this thank you
Don't think so.
Theory : There is ALWAYS 2 oranges in a bag.
Observation : A bag containing 5 oranges.
Theory is disproved.
New theory : There is not *necessarily* 2 oranges in a bag.
http://einstein.stanford.edu/Media/Simple_Expt_Anima-Flash.html has a simple animation explaining the gravity probe B experiment.
I love this sort of post; spewing text from start to finish. I know I'll part with my cash after reading an advert of this nature. The amount of effort displayed in the advert will equal the amount of effort I'll receive in supply and customer service, and that means you have a sale!
Please spew some more numbers in my direction. I can't get enough of them.
This post contains benzene, nitrosamines, formaldehyde and hydrogen cyanide.
Brilliant. Making spam fun one post at a time :)
Invaders must die
You didn't disprove the theory. The word "always" can also mean "at least". Your observation actually proved a bag that contains 5 oranges contains at least 2 oranges as well.
The problem is you don't "believe" there are still 2 oranges in the bag(typical climate change logic). Yoda said it well, "That is why you fail." Seriously you don't understand logic. You sure as hell don't go around changing a theory based on 1 observation. You also don't make new "theories" based on that same 1 observation(although climate change groupies like to muddle the word "theory" as much as possible so they can claim they are always right). This is also why many "scientists" make claims in English rather than using mathematical logic expressions, so they always have an out. Maybe you do understand the problems with describing logic with natural language, preferring to muddle the issue and claim absolute truths, knowing full well they are not.
And please, keep up the good work of including the URL so its real easy to add to the ban list. Then, if this ever becomes a real business with useful, well-priced products it will still go bust because no-one will know about it.
ok - I agree , my mistake. I wasn't pedantic enough.
I should have said 'ALWAYS EXACTLY 2 oranges'
And now I have a bag with 1 orange.
So now 'at least exactly 2 oranges' is false.
There is no *necessarily* involved.
Where exactly did this theory 'A is not *necessarily* so and so' spring from. Sound a bit natural language and muddled to me.
Interesting. Can't change a theory on one observation ? Is there some ISO specified number of times that an observation must be seen to be counted ?
I have seen 1 and 5 oranges in a bag. 2 results - is that enough.
And WTF does climate change logic have to do with this ? Yoda say 'Shoulder chip on you may have'.
BTW. You spelled *neccesarily* (sic) wrong.
Totally off topic, I know, but I for one think it's a good thing that we can't mod stuff up so easily anymore.
Good posts still get modded up (eventually), and you can use the slides to select the level you want to read. At least, the score is now a way to select the posts. It used to be a matter of just getting a post in quickly, which would get modded up simply because everybody had mod points. And to be read, you had to get 5 points.
Now, good posts might have only 2-3 points. 4-5 points are excellent posts.
That's great... but given a quantum physics and that little bugger of a concept known as the observer effect (basically ALL experience is subjective to the observer - even scientific ones...) how do we know the results we are recording are actual vs what we believe we should be experiencing and therefore are willing to see? Sure I could be wrong in what I am saying, but let me know and I'll entertain it in my field of awareness as possibility and perhaps I'll experience it differently...or maybe not. ;) Yes, quite a bugger that little observer effect concept is!
I usually bow out of stories like this, but must make one comment:
Anybody who thinks time is important as a metric is seriously missing the point.
... but the Chinese are actively doing it - as seen here in 2007.
Sometimes we to just shut up and do it else we'll have deja vu like solar energy or nuclear power
Finally I can put an end to all of those naysayers of gravitation theory!
We have disproved part of your assertion with an example of empirical confirmation here. Namely, there was an opportunity for using this observation to distinguish between the general relativity (GR) hypothesis and some situations that looked like GR according to older experiments, but weren't under this subtler observation.
Relativity and black holes look like bugs in a not-very-well thought-out physics simulation. This sort of thing makes me wonder if the universe isn't just some extra-dimensional college kid's thesis project on how to find the best way to turn hydrogen into plutonium.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
There is so much wrong with this article I don't know where to begin. I think it will suffice to say that looking for evidence to support what you *want* to be proven correct will often get in the way of gathering evidence for what is truly correct.
On little pet peeve, who is to say earth is spinning the magnetic field, and not the magnetic vortex spinning the earth?
- Dan.
However the Stanford satellite supposedly is ten times more accurate
From what I have heard, the reason it took 52 years to get this spacecraft into space was political, not technical.
There is no doubt that the technology developed to measure these parameters is very impressive. The real question is whether or not it was worth the effort.
When I was at JPL in the 1980s a person who had published numerous papers in both experimental and theoretical relativity explained why scientists within the space program were not supporting this project. Since this conversation took place thirty years ago I must paraphrase:
"No modern theory of gravity predicts anything else, and if the measurements showed anything but the predicted results it would be assumed to be an experimental error. Unlike the technology used to search for gravitational radiation (which is also used to study the atmospheres of planets), the hardware in this spacecraft cannot be used for any other scientific experiment."
So for 52 years the money has been used for other science. For a much more worthy project read about the recently canceled LISA project.
If you wish to read about the politics of how a science project is chosen by NASA I can think of no better description that Steven W. Squyres' "Roving Mars" where he describes how the Mars Rovers were nearly canceled.
How much time money and effort has been spent on this useless space endeavor? Scientists should be more focused on trying to solve the problems here on Earth before wasting their time with what's up in space.
Sometimes I wonder if these great minds that pops up from time to time (Newton, Copernicus, Einstein etc) are really one of us. It's funny how they appear, completely revolutionize a field or offer a world changing new perspective and then disappear, just to have us mere mortals work for years and decades to understand, confirm and accept it. Applause again for Einstein, you are a bit creepy to be completely honest.
Can I light a sig ?
It's search rank manipulation spam, not a direct advertisement. They don't care about the formatting or human readablity since it's just raw data to mess with search engine algorithms.
Imagine Natalie Portman, as if she were immersed in hot grits...
Theory : There is ALWAYS 2 oranges in a bag.
Observation : A bag containing 5 oranges.
Conclusion: 2 oranges in a bag can reproduce
My understanding was that (satellite-based) GPS would give you a drastically inaccurate position reading without an algorithmic correction for frame-dragging. If so, it would seem that part of Einstein's predictions were validated quite a few years ago.
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
I think it will suffice to say that looking for evidence to support what you *want* to be proven correct will often get in the way of gathering evidence for what is truly correct.
Hasn't worked that way in the past.
On little pet peeve, who is to say earth is spinning the magnetic field, and not the magnetic vortex spinning the earth?
Consider the relative difference in energy from the rotational energy of a spinning Earth and the energy content of the magnetic fields of Earth. I haven't done the math, but I bet the latter is a bunch of zeroes smaller than the former. That in itself is a very good reason for the interpretation.
Same goes for the claim that the Solar System revolves around the Sun. It's actually around a common center of gravity (which theoretically can be outside the Sun). But the Sun is by far more massive than the rest of the Solar System combined, meaning it is the dominant object.
The goal was to get numerical results to 1% accuracy, and the actual measurements only achieved %19 percent accuracy. This was due to a design error.
On top of that, other researchers made better measurements using other much cheaper satellites.
So they got scooped and their final results were not what they had planned. Not a complete failure, but not a real success either.
Why is Snark Required?
This is cool news! When I first got deep into physics, I often considered the ideal of; "a hot air balloon floating(not) around an earth without an atmosphere", and "would the balloon be dragged around the plaint as it rotates(by gravity)?", now I feel satisfied that know the answer!
;)
And also the intermediary step of Lagrange point between two stars too of course...
Which leads to the next n question:
If you took our solar system and placed it at the most significant Lagrange point between two galaxy's, would our understanding of physical constants change?
So my next fav. question is, "Do black-holes frame drag at a predictable rate(when compared to the Earth and Sun)?"
And, rinse and repeat the original experiment under those condition.
At the end of the day, an experiment is only as accurate as the instrument used to measure it; this steps it up a notch!