Gravity Probe B confirms two Einstein theories

May 04, 2011
Einstein's predicted geodetic and frame- dragging effects, and the Schiff Equation for calculating them.

(PhysOrg.com) -- 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 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.

After 52 years of conceiving, building, testing and waiting, the science satellite has determined both effects with unprecedented precision by pointing at a single star, IM Pegasi, while in a around Earth. If gravity did not affect space and time, Gravity Probe B's gyroscopes would point in the same direction forever while in orbit. But in confirmation of Einstein's general theory of relativity, the gyroscopes experienced measurable, minute changes in the direction of their spin as they were pulled by Earth's gravity.

The findings appear online in the journal .

"Imagine the Earth as if it were immersed in honey. As the planet rotated its axis and orbited the Sun, the honey around it would warp and swirl, and it's the same with space and time," said Francis Everitt, a Stanford physicist and principal investigator for Gravity Probe B.

"GP-B confirmed two of the most profound predictions of Einstein's universe, having far-reaching implications across astrophysics research," Everitt said. "Likewise, the decades of technological innovation behind the mission will have a lasting legacy on Earth and in space."

Stanford has been NASA's prime contractor for the mission and was responsible for the design and integration of the science instrument and for mission operations and data analysis.

Much of the technology needed to test Einstein's theory had not yet been invented in 1959 when Leonard Schiff, head of Stanford's physics department, and George E. Pugh of the Defense Department independently proposed to observe the precession of a gyroscope in an Earth-orbiting satellite with respect to a distant star. Toward that end, Schiff teamed up with Stanford colleagues William Fairbank and Robert Cannon and subsequently, in 1962, recruited Everitt.

NASA came on board in 1963 with the initial funding to develop a relativity gyroscope experiment. Forty-one years later, the was launched into orbit about 400 miles above Earth.

The project was soon beset by problems and disappointment when an unexpected wobble in the gyroscopes changed their orientation and interfered with the data. It took years for a team of scientists to sift through the muddy data and salvage the information they needed.

Despite the setback, Gravity Probe B's decades of development led to groundbreaking technologies to control environmental disturbances on spacecraft, such as aerodynamic drag, magnetic fields and thermal variations. The mission's star tracker and gyroscopes were the most precise ever designed and produced.

Innovations enabled by GP-B have been used in the Global Positioning System, such as carrier-phase differential GPS, with its precision positioning that can allow an airplane to land unaided. Additional GP-B technologies were applied to NASA's Cosmic Background Explorer mission, which determined the universe's background radiation. That measurement is the underpinning of the "big bang theory" and led to the Nobel Prize for NASA's John Mather.

"The mission results will have a long-term impact on the work of theoretical physicists for years to come," said Bill Danchi, senior astrophysicist and program scientist at NASA Headquarters in Washington. "Every future challenge to Einstein's theories of general relativity will have to seek more precise measurements than the remarkable work GP-B accomplished."

Over the course of its mission, GP-B advanced the frontiers of knowledge and provided a practical training ground for 100 doctoral students and 15 master's degree candidates at universities across the United States. Over 350 undergraduates and more than four dozen high school students also worked on the project, alongside leading scientists and aerospace engineers from industry and government.

Sally Ride, the first American female astronaut in space, worked on GP-B while studying at Stanford. Another was Nobel Laureate Eric Cornell, who also studied at Stanford.

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Skultch
4.8 / 5 (9) May 04, 2011
How does this affect our recent time discussions? Does it also prove that time is inherently linked to 3D space? Is there room for an even more fundamental understanding?
Pharago
1.6 / 5 (27) May 04, 2011
this project lost it's credibility a few years ago
Husky
3.8 / 5 (9) May 04, 2011
Time, as in spacetime fabric would not needed , dragging of spacegeometry would be enough to add a numerical branch to the tree of state changes/entropy in a volume of space, so time merely becomes a derived value of the space changes rather than intrinsic property
J-n
4.5 / 5 (13) May 04, 2011
this project lost it's credibility a few years ago


I must have missed it somewhere in the past, but why is that?
High_Evolutionary
2.1 / 5 (7) May 04, 2011
Read the paper when it's available. :)
Resonance
4 / 5 (22) May 04, 2011
It never lost its credibility. They had technical difficulties with the gyroscopes but then took their (very small) malfunction into account. The results match the theory; moreover, they have taken enough data to make the small malfunction neglible.

Please don't write ignorant comments on a science forum. This applies to omatumr and QC as well or anyone else who think they are knowledgeable in physics just by reading wiki articles.
J-n
3.3 / 5 (15) May 04, 2011
It never lost its credibility. They had technical difficulties with the gyroscopes but then took their (very small) malfunction into account.


Thanks for clearing it up for me, I had not heard anything about the Gravity Probe B having lost their credibility in some sort of scandal or something, and thought i might have completely missed something big.

I will say that the whack-jobs here at physorg do actually make my day go by faster here at work. Just there should be some newbie guide pointing them out so no one confuses them with people who are honest in their discourse.
Skeptic_Heretic
4.7 / 5 (15) May 04, 2011
Read the paper when it's available. :)

I read many a paper on Hubble, and what an utter failure it was.

I also have some of the most beautiful pictures of far distant objects and galaxies on the walls of my office and home due to the corrections made after those papers came out.

One should not dismiss the ability to salvage signal when the noise is a little greater than expected.
Just there should be some newbie guide pointing them out so no one confuses them with people who are honest in their discourse.
Check my profile.
J-n
not rated yet May 04, 2011
Check my profile.


Thanks!
Quantum_Conundrum
May 04, 2011
This comment has been removed by a moderator.
SCVGoodToGo
3.5 / 5 (11) May 04, 2011
An LCD monitor is evidence of the sky fairy?
TabulaMentis
1.5 / 5 (33) May 04, 2011
YES! Thank God. I am a Christian and a Creationist.

I am always shocked at the amount of atheists who visit this site. After all your studying of science, math, and nature, you still haven't found God even though his evidences are right in front of your faces.
Ask these highly experienced scientists how gravity is created and see what kind of an answer you get. They do not have the foggiest idea what creates gravity.
SemiNerd
4 / 5 (25) May 04, 2011
Check my profile.


YES! Thank God. I am a Christian and a Creationist.

I am always shocked at the amount of atheists who visit this site. After all your studying of science, math, and nature, you still haven't found God even though his evidences are right in front of your faces.

Please get off your soapbox QC. Talking about religion or politics violates the Comment guidelines and I will be reporting you from this point out.
dirk_bruere
4.2 / 5 (17) May 04, 2011
Why does Einstein always bring out the nuts?
jselin
3.4 / 5 (17) May 04, 2011
Ask these highly experienced scientists how gravity is created and see what kind of an answer you get. They do not have the foggiest idea what creates gravity.


Gravity exists because baby Jesus wants it that way ;)
macsglen
4.1 / 5 (16) May 04, 2011
I haven't missed God since I gave up on religion. I wouldn't miss QC if he were banned from this forum.

As to knowing where gravity comes from, that's just another of the many things we have yet to discover, but this is what science is for. One day, we will know.
Question
2.8 / 5 (8) May 04, 2011
YES! Thank God. I am a Christian and a Creationist.

I am always shocked at the amount of atheists who visit this site. After all your studying of science, math, and nature, you still haven't found God even though his evidences are right in front of your faces.
Ask these highly experienced scientists how gravity is created and see what kind of an answer you get. They do not have the foggiest idea what creates gravity.

You want an explanation as to how gravity works? Click on my user name. There is a link posted there. Go to page 37 for a classical physics explanation that involves only time and heat.

TomSeabury
3.7 / 5 (3) May 04, 2011
Not a science guy, but How do you conclude based only on the gravitational attraction between two objects that gravity tends to wrap around a large rotating mass. Along the same vein why was it concluded in the solar eclipse experiment that space was bent by gravitational pull of the sun when in fact it was only the light (space has no mass to pull on).
Moebius
1.4 / 5 (8) May 04, 2011
Didn't Michelson Morley prove frame dragging long ago?
ubavontuba
3.9 / 5 (19) May 04, 2011
How does this affect our recent time discussions?
It confirms predictions of GR - which strengthens the notion of "spacetime."

Does it also prove that time is inherently linked to 3D space?
Yes - insofar as Einstein's theory can be experimentally verified.

Is there room for an even more fundamental understanding?
Possibly. The string theorists, for instance, surely hope so. Only time will tell (pun intended).

ubavontuba
3.6 / 5 (17) May 04, 2011
this project lost it's credibility a few years ago

Not really. Initially, they easily confirmed geodetic precession.

The frame-dragging signal was lost for a time, but they carefully extricated it from the data.

"Initial results confirmed the expected geodetic effect to an accuracy of about 1%. The expected frame-dragging effect was similar in magnitude to the current noise level (the noise being dominated by initially unmodeled effects). Work is continuing to model and account for these sources of unintended signal, thus permitting extraction of the frame-dragging signal if it exists at the expected level. By August 2008 the uncertainty in the frame-dragging signal had been reduced to 15%,[5] and the December 2008 NASA report indicated that the geodetic effect was confirmed to better than 0.5%."

http://en.wikiped..._Probe_B

hush1
3.2 / 5 (6) May 04, 2011
After NASA funding stopped, I did not expect to read or hear more from GP-B. I was wrong.
ubavontuba
3 / 5 (13) May 04, 2011
Why does Einstein always bring out the nuts?


"A question that sometimes drives me hazy: am I or are the others crazy?"
-Albert Einstein
Shootist
2.5 / 5 (11) May 04, 2011
YES! Thank God. I am a Christian and a Creationist.

I am always shocked at the amount of atheists who visit this site. After all your studying of science, math, and nature, you still haven't found God even though his evidences are right in front of your faces.
Ask these highly experienced scientists how gravity is created and see what kind of an answer you get. They do not have the foggiest idea what creates gravity.


No? Gravity is caused by mass warping space-time.
Shootist
3.2 / 5 (14) May 04, 2011
why was it concluded in the solar eclipse experiment that space was bent by gravitational pull of the sun when in fact it was only the light (space has no mass to pull on).


Light follows the curvature of space-time. A star that was physically behind the sun was still visible because its light had followed the warped space-time.

Light has no mass either.
Pharago
1.8 / 5 (10) May 05, 2011
Light follows the curvature of space-time. A star that was physically behind the sun was still visible because its light had followed the warped space-time.


We are used to bend beams with magnetic fields, maybe the sun's magnetic field was enought to bend the light coming from that star, woah! that explanation dosn't need a fabric of space-time...
Polestar
3.3 / 5 (7) May 05, 2011
Earlier reports stated they found unexpected precession, polhode noise and torque 100 times larger than expected, but then they applied 90% "error correction" - and voila - fixed their results. This thing smells. I do not doubt Einstein but I think the GP-B team has lost all credibility. Look forward to seeing exactly what assumptions were made in the corrections. Let science be the judge.
jamesrm
3 / 5 (3) May 05, 2011
I think its fair to say the recovered data is not totally unambiguous considering the amount of fitting that they probably needed to do to extract a signal, the probe was de-orbited/destroyed so they can't double check their data fix.

This probe cost a lot of money ($750 million) and took years to build, people had egg on their faces when it failed it main mission; finding frame drag.
frajo
2 / 5 (4) May 05, 2011
I am always shocked at the amount of atheists who visit this site. After all your studying of science, math, and nature, you still haven't found God even though his evidences are right in front of your faces.
Once you and your militant atheist playmates ("you evil, me good") get out of your sand box maybe you'll tackle the theodicy question.
It's not about whether there are godesses but about why humans should stand by their side if they exist.
dav_i
5 / 5 (4) May 05, 2011
We are used to bend beams with magnetic fields, maybe the sun's magnetic field was enought to bend the light coming from that star, woah! that explanation dosn't need a fabric of space-time...

This article is talking about further experimental evidence for the confirmation of Einstein's Theory of General Relativity, which predicts gravitational lensing and this is confirmed to great accuracy.
Once you understand it, GR is one of the most beautiful and intuitive theories around.
Pkunk_
1.4 / 5 (9) May 05, 2011
Wash, Rinse , Repeat.

650M $ down the drain for a most basic "error" . Instead of dumping more money down this abortion they should've started afresh. Only way of finding out if the instruments are wrong or it's just an an invitiation to conspiracy theories.
Isaacsname
2.7 / 5 (3) May 05, 2011
why was it concluded in the solar eclipse experiment that space was bent by gravitational pull of the sun when in fact it was only the light (space has no mass to pull on).


Light follows the curvature of space-time. A star that was physically behind the sun was still visible because its light had followed the warped space-time.

Light has no mass either.


I was under the impression that photons have inertial mass, is that wrong ?
macsglen
4.3 / 5 (12) May 05, 2011
@kevinrtrs -- you said:
This human cell has the incredible appearance of design. BUt guess what? The atheists want us to accept that such sophistication can arise purely by chance.
Not by CHANCE, bonehead -- by the physical laws of the universe, which, unlike religion, are knowable and provable -- not to mention USEFUL.
Noumenon
4.8 / 5 (51) May 05, 2011
why was it concluded in the solar eclipse experiment that space was bent by gravitational pull of the sun when in fact it was only the light (space has no mass to pull on).


Light follows the curvature of space-time. A star that was physically behind the sun was still visible because its light had followed the warped space-time.

Light has no mass either.


I was under the impression that photons have inertial mass, is that wrong ?

Yes, photon's have momentum and thus mass equivalency. In fact because of this mass-energy equivalency, one could calculate Newton's predictions of the bending of star light near the Sun,... it is half that of Einstein's GR predictions.
jamesrm
3.7 / 5 (6) May 05, 2011
you are arguing with people who think the cosmic microwave background is the echo of gods alarm clock, I'd think many would have better things to do :)
Noumenon
4.5 / 5 (53) May 05, 2011
@kevinrtrs -- you said:
This human cell has the incredible appearance of design. BUt guess what? The atheists want us to accept that such sophistication can arise purely by chance.
Not by CHANCE, bonehead -- by the physical laws of the universe, which, unlike religion, are knowable and provable -- not to mention USEFUL.

Careful, he may ask you how did the "laws of physics" come about, they appear designed to cause an effect,...

I look at atheists with the same sigh as I do believers.
Gawad
4.6 / 5 (11) May 05, 2011
@kevinrtrs -- you said:
This human cell has the incredible appearance of design. BUt guess what? The atheists want us to accept that such sophistication can arise purely by chance.
Not by CHANCE, bonehead -- by the physical laws of the universe, which, unlike religion, are knowable and provable -- not to mention USEFUL.


Bonehead? Oh my, no, no. One of our teams has been keeping a close eye on Kevin for some time and in a paper we are about to submit to Physical Review Letters B we propose that the structure you refer to as a Bonehead is actually an instance of collapsed hard vacuum encased in neutronium.

The neutronium surface appears to be the only thing preventing the cerebral bubble nucleation from spreading outwards into the rest of our universe at c.

We are carefully going over our results to make sure nothing in there might be erroneously construed as supporting neutron repulsion.

Cheers.
Pharago
4 / 5 (2) May 05, 2011
This article is talking about further experimental evidence for the confirmation of Einstein's Theory of General Relativity, which predicts gravitational lensing and this is confirmed to great accuracy.
Once you understand it, GR is one of the most beautiful and intuitive theories around.


Yes, I know, I did follow the experiment with great expectation, prove or disprove, those guys did a magnificent job setting up all the gyros, the most perfect spheres made to date, what they wanted to measure was so tiny that there was almost no room for error, and then it happen, later on, the unexpected delay on the release of data, or the delay in the interpretation of the gathered scientific data didn't help the credibility, in fact I did dismiss the experiment a couple years ago and never expected of them to arrive at any useful conclusion.
Now we are in 2011, and this release pops out, maybe I'm being too skeptic, maybe we will need to repeat the experiment on the orbit of jupiter.
TabulaMentis
2 / 5 (4) May 05, 2011
You want an explanation as to how gravity works? Click on my user name. There is a link posted there. Go to page 37 for a classical physics explanation that involves only time and heat.
Excellent job in explaining your version of how gravity is created. I only wish you had illustrations to help support the idea.
Skeptic_Heretic
3.7 / 5 (3) May 05, 2011
Kevin,
The atheists have no clue as to where and how that cell comes from in the first place but they want to stamp their opinion of the origin as being the official and only one to be tolerated. If it looks like design, works like designed, repairs like it was designed then it must have been designed. Only atheists deny it.
Simple refutation here:
http://youtu.be/bq9qbm5oX1k
frukc
2.3 / 5 (3) May 05, 2011
Earlier reports stated they found unexpected precession, polhode noise and torque 100 times larger than expected, but then they applied 90% "error correction" - and voila - fixed their results. This thing smells. I do not doubt Einstein but I think the GP-B team has lost all credibility. Look forward to seeing exactly what assumptions were made in the corrections. Let science be the judge.

jup... change the data the way, it will support einsteins theory - and voila! that worries me too.
vacuum-mechanics
1.8 / 5 (5) May 06, 2011
According to the famous Michelson-Morley experiment test which was interpreted that there is no ether frame (here, space-time frame) dragging with the earth, doesnt this contradict to the result of the GP-B?
vacuum-mechanics
1.8 / 5 (5) May 06, 2011
According to the famous Michelson-Morley experiment test which was interpreted that there is no ether frame (here, space-time frame) dragging with the earth, doesnt this contradict to the result of the GP-B?
xamien
1 / 5 (1) May 06, 2011
I guess a semester spent in basic college chemistry would elude the Zombie Jesus fans, too.
Warrensn
5 / 5 (2) May 06, 2011
"Light has no mass either."

Shootist, you're funny.
You wrote this as a comment on a story proving Einstein correct.
Yet you deny E=MC^2? That was proven long ago. Would you care to revise your comment?
frajo
4.2 / 5 (11) May 06, 2011
This human cell has the incredible appearance of design.
No, as it is far more complex than any designed object.

The atheists want us to accept that such sophistication can arise purely by chance.
No. The atheists don't want anything from you. And no, there's no chance involved, as others have pointed out.

they want to stamp their opinion of the origin as being the official and only one to be tolerated.
No, you're entitled to your opinion. But as it is not based on the principle of falsifiability, it's not a scientific opinion. You do expect objections in form of scientific opinions, so don't complain.

Apart from that central principle, the discourse between Creationists and scientists is boring. If you want some really tough discussion have a dispute with Catholics.
ubavontuba
3 / 5 (10) May 06, 2011
No, you're entitled to your opinion. But as it is not based on the principle of falsifiability, it's not a scientific opinion.
I'd just like to mention a little technicality...

Both the creationists' and evolutionists' hypotheses for the cause of life on (or introduction of life to) Earth are generally unfalsifiable.

Even if scientists create spontaneous life in a test tube someday (unlikely), there's no guarantee that's how it occurred on Earth (or elsewhere). All that might be said in this case is (supposing the experiment matches particular primordial conditions) it's a strong justification for the "argument" life arose in just such a manner. But until then, arguing the point is like spitting into the wind...

All we can say for certain is; for hundreds of millions of years, life has been evolving and changing on Earth. But even this only falsifies some (not all) creationists' arguments.

Isn't science fun?

saltire
5 / 5 (1) May 06, 2011

The illustration only depicts the scenario of a body approaching on an equatorial plane -- like the infamous ball on a rubber sheet causing a dimple which captures an approaching ball. In other words gravity causes the dimple, which in turn causes gravity to "attract" the incoming ball. Gravity is used to explain gravity!!!! --- Not too convincing.
I think Einstein may have got it right for the wrong reasons. Something like describing a circle from some point other than the center. The same results can be obtained, I believe, without the mental gymnastics of bent space etc.
I have authored an e-book "The Dynamic Ether which postulates The universe is a disturbed field of pure energy seeking equilibrium. It seems to me that this single supposition is the only way sense can be made of dark matter, dark energy, dark flow, not to mention gravity.
ubavontuba
2.5 / 5 (8) May 07, 2011
Gravity is used to explain gravity!!!!
Yeah, the rubber sheet thing is old and tired. At best, it helps people understand the "shape" of space, without explaining the cause.

I think Einstein may have got it right for the wrong reasons.
No. He got it right, but the concepts are complex and often difficult to understand.

Like the 2D rubber sheet being warped into a higher (third) dimension by gravity, space is warped into a higher (fourth) dimension by mass/energy.

PinkElephant
4.2 / 5 (5) May 07, 2011
it helps people understand the "shape" of space, without explaining the cause
It explains the cause as warping of space and time. In a flat spacetime, objects travel in straight lines due to inertia. In a warped spacetime, objects still travel on geodesics, except the geodesics are no longer straight lines. But perhaps you're looking for the underlying mechanism of HOW space is stretched, and time slowed down?
space is warped into a higher (fourth) dimension by mass/energy
Not in GR it isn't. It's more like a block of glass with non-uniform but smoothly changing refraction index (with photons representing inertial reference frames), or a volume of ideal gas with similarly non-uniform, smoothly changing temperature (with phonons representing inertial reference frames.)
Roach
5 / 5 (2) May 07, 2011
So the Christians have been removed, If a mod would go ahead and get rid of the anti-christian comments, the 3 remaining comments might have something to do with the subject at hand.

Now, Posting on topic, I understand the effects on space time by a rotating mass, but what is the other theory proved, just the generalized distortion resulting from said mass?

I've been off Physorg for a while, someone please tell me all the forums are christians versus anti christians, that or go ahead and ban me so I don't waste my time. K-Thx.
Isaacsname
3 / 5 (2) May 07, 2011

I was under the impression that photons have inertial mass, is that wrong ?
Yes, photon's have momentum and thus mass equivalency. In fact because of this mass-energy equivalency, one could calculate Newton's predictions of the bending of star light near the Sun,... it is half that of Einstein's GR predictions.

Ok thanks, I was confused, still learning :) Do these experiments offer any compelling reason why gravitational mass has to equal inertial mass ? I am under the assumption this is still a puzzling relationship (?)
hush1
2.5 / 5 (4) May 07, 2011
@PE
Is thinking in terms of brachistochrone/tautochrone cycloids a helpful/useful mathematical tool/concept when the uninitiated enter the world of GR?

Or are the absolute time references a "ball and chain" and later difficult to discard in regards to the physical?

Under the assumption you were asked to teach GR with what you know now.

Isaacsname
3 / 5 (2) May 07, 2011
Is ZPM a result of this effect of gravitational dragging ?

http://www.nasa.g...ZPM.html
hush1
1 / 5 (1) May 07, 2011
@Isaacs
This answers your question.
Well, for me, anyway.

www.elissarllc.co...News.pdf
validationoflife
3.6 / 5 (7) May 07, 2011
Why is it that almost any forum that attempts to discuss science ends up with a bunch of religious zealots? There are plenty of religious forums for that sort of this. Please leave the science forums for real science discussions.
Religion relies on faith, meaning a belief in things that cannot be proven. Science is based on facts that can be proven in repeatable experiments. Please, lets keep the two separate!
In view of the above statement, I really hate to have to do this but its necessary to show I am not biased one way or the other. I am a Christian. That being said, the more I learn in science the stronger my faith becomes because I see how wondrously everything is designed. The proof the geodetic effect and frame-dragging are cases in point, as are evolution, the age of the Earth and so on. I dont need science to believe in God but, thanks to God I am here to believe in science.
PinkElephant
5 / 5 (3) May 07, 2011
@hush1,
Is thinking in terms of brachistochrone/tautochrone cycloids a helpful/useful mathematical tool/concept when the uninitiated enter the world of GR?
Not very useful, IMHO. Indeed, they can confuse things since both rely on Newtonian gravity for definition, which is modeled as a force. In GR there is no force of gravity per se, there's only a warped coordinate system. This is partly what makes gravity in GR so freakishly hard to bring under a common denominator into a "Theory of Everything" together with actual "forces" such as the electroweak force. The key notion you're zeroing in on, is inertial movement along a geodesic; however here the key idea is that of a *shortest* path between any two points on a manifold, rather than "fastest" path or somehow an equivalent one in terms of "transit time". In SR/GR, time participates in the definition of an "interval" (which is related to distance), on equal footing with the 3 spatial coordinates. Best to tackle SR first...
ubavontuba
2.1 / 5 (7) May 07, 2011
But perhaps you're looking for the underlying mechanism of HOW space is stretched, and time slowed down?
I think it was clear that "saltire" was complaining the GR rubber sheet analogy doesn't explain WHY mass/energy bends spacetime.

It's more like a block of glass with non-uniform but smoothly changing refraction index (with photons representing inertial reference frames), or a volume of ideal gas with similarly non-uniform, smoothly changing temperature (with phonons representing inertial reference frames.)
Like that's a good argument to use against an Ether proponent like saltire. It looks like you're supporting an Ether concept, yourself!

I mean really. Using "a volume of ideal gas" (and similar concepts) in an Ether argument, is like poring gasoline on a flame!

"First Einstein said you must think of space and time together: this is called spacetime..."

http://www.gravit...Time.pdf

Pyle
4.4 / 5 (7) May 07, 2011
Roach:
Now, Posting on topic, I understand the effects on space time by a rotating mass, but what is the other theory proved, just the generalized distortion resulting from said mass?

One is the general distortion of space time caused by a mass. This leads to gravity, lensing and the like. Pretty much Einstein's gravity.

The second is the whole dragging part related to the rotation of the object.

Einstein's theory predicts that a rotating body will warp spacetime differently than a non-rotating body. As such this experiment has attempted to see whether or not this is true. If no frame dragging precession then GR has a flaw.
Martian00
3 / 5 (3) May 08, 2011
Isn't it interesting to know.
When experiments do not match with the theory, it is due to technical problem or instrumental errors or miscalculation. But when experiments match with theory, the equipment is flawless.
hush1
2 / 5 (3) May 08, 2011
@PE

Yes. Anyone not finding your wonderful wording to point out the vagueness of a notion I was not able to spontaneously express, misses the point of discussion. Your focus, "...zeroing in on..." found the wording that reaches a greater understanding about a challenge we are anxious to understand more of and eventually solve.
Thanks
Skeptic_Heretic
3.6 / 5 (7) May 08, 2011
Both the creationists' and evolutionists' hypotheses for the cause of life on (or introduction of life to) Earth are generally unfalsifiable.
Evolution has absolutely zero bearing on the origin of life. It only describes what happens to life over time.

Further, 'evolutionist' is a slur that ignorant people use to describe people who pay attention to scientific theory. I'm surprised to see you use it.
ubavontuba
2 / 5 (8) May 08, 2011
Both the creationists' and evolutionists' hypotheses for the cause of life on (or introduction of life to) Earth are generally unfalsifiable.
Evolution has absolutely zero bearing on the origin of life. It only describes what happens to life over time.
How's this substantively different than what I wrote?

Further, 'evolutionist' is a slur that ignorant people use to describe people who pay attention to scientific theory. I'm surprised to see you use it.
What would you prefer? "Darwinist?" Surely, "biologist" is too broad a term for this context. And, "evolutionist" is in the dictionary:

evolutionist:
a person who believes in a theory of evolution,

http://www.thefre...utionist
vacuum-mechanics
1 / 5 (2) May 08, 2011
Roach:
Einstein's theory predicts that a rotating body will warp spacetime differently than a non-rotating body. As such this experiment has attempted to see whether or not this is true. If no frame dragging precession then GR has a flaw.


How space-time was wraped by gravity?
Skeptic_Heretic
4.2 / 5 (6) May 09, 2011
What would you prefer? "Darwinist?" Surely, "biologist" is too broad a term for this context. And, "evolutionist" is in the dictionary:

evolutionist:
a person who believes in a theory of evolution,
How about we don't label people based on their acceptance of a fact?
AmritSorli
1.6 / 5 (7) May 09, 2011
would be more precise to say "space is warped" as time is merely numerical order of earth motion in space
GSwift7
1.5 / 5 (6) May 09, 2011
why was it concluded in the solar eclipse experiment that space was bent by gravitational pull of the sun when in fact it was only the light


There's a good non-science story behind that one. In post-WW2 times, British scientists set out to prove a theory proposed by a German physicist (Einstein) and came back happily confirming that observation agreed with the theory. It was front page news around the world due to political reasons. Years later is was found that the Britts' sloppy work made the results invalid (uncertainty greater than observed effect), but by then the results had already been confirmed by much more accurate observations, so they got lucky and got it right by pure blind luck.

However, keep in mind that Relativity is still just one theory amongst several others. The results here seem to agree with the predictions, so it adds confidence in relativity, but does not preclude other posibilities outright. As stated above, relativity still doesn't fit with quanta
AmritSorli
1 / 5 (4) May 09, 2011
would be more precise to say "space is warped" as time is merely numerical order of earth motion in space


http://www.youtub...QBG2eouQ
ubavontuba
2.5 / 5 (8) May 09, 2011
How about we don't label people based on their acceptance of a fact?
Then how would we distinguish one group from another?

What would we call historians then? "People who believe in chronological records of events that are usually written by the victors" ...perhaps?

Maybe mathematicians might become, "people who believe in using numbers and symbols to quantify measurement, properties, and relationships of quantities and sets?"

These descriptions seem rather pointlessly unwieldy, don't you think?

Using "people who believe in evolution" every time I wish to make such a distinction, is rather unwieldy too, don't you think?

And besides, just where did you get the notion "evolutionist" is a slur? I identify myself as an evolutionist, and I don't have a problem with it.

frajo
3 / 5 (2) May 10, 2011
In post-WW2 times, British scientists set out to prove a theory proposed by a German physicist (Einstein) and came back happily confirming that observation agreed with the theory.
Are you referring to Sir Arthur Eddington's observation of the Solar eclipse of 29 May 1919?
AmritSorli
1 / 5 (7) May 10, 2011
This gravity probe B proves following:
-cosmic space is 3D - because all the angles are measured in three directions X,Y,Z
-cosmic space has granular structure - frame dragging
outcome of Gravity probe B is also that time we measure with clocks cannot be the 4th dimension of space:
http://www.physor...ion.html
ubavontuba
3 / 5 (10) May 10, 2011
This gravity probe B proves following:
-cosmic space is 3D - because all the angles are measured in three directions X,Y,Z
-cosmic space has granular structure - frame dragging
outcome of Gravity probe B is also that time we measure with clocks cannot be the 4th dimension of space:
Frame dragging is a prediction of GR and ergo is a prediction rooted in spacetime.

You can go on insisting the world is flat if you want, but you can't make it flat simply by insisting it is. We know better.

Skeptic_Heretic
5 / 5 (11) May 10, 2011
frame dragging
outcome of Gravity probe B is also that time we measure with clocks cannot be the 4th dimension of space:
If I send you an invite to a party what 4 pieces of information do you need to get there?

Latitude, longitude, altitude, time.
Those are the 4 dimensions which define where the party is. In all of observable spacetime, to make any determinant observation of an object, you must have all 4 of these components. Those are the 4 dimensions of our existence.
hush1
1 / 5 (2) May 10, 2011
...relativity still doesn't fit with quanta


...and so the story never ends and those two lived happily ever after. In a place where the needs of those two never went unfulfilled. In a place infinite in size, where 'fit' was not a question.

The place? The place is of unimaginable beauty.
The place is called:
Einstein's mind.
Visiting hours are restricted to your imagination. :)
All visitors welcome.
GSwift7
1 / 5 (2) May 10, 2011
Are you referring to Sir Arthur Eddington's observation of the Solar eclipse of 29 May 1919?


Yes. Oh sorry, typo. Post WW-1 of course. Thanks.
AmritSorli
1 / 5 (4) May 10, 2011
3D space can also be curved

This gravity probe B proves following:
-cosmic space is 3D - because all the angles are measured in three directions X,Y,Z
-cosmic space has granular structure - frame dragging
outcome of Gravity probe B is also that time we measure with clocks cannot be the 4th dimension of space:
Frame dragging is a prediction of GR and ergo is a prediction rooted in spacetime.

You can go on insisting the world is flat if you want, but you can't make it flat simply by insisting it is. We know better.


LarsKristensen
1 / 5 (3) May 11, 2011
Two identical substance masses orbiting each other, after Einstein's view, each creating an indentation in spacetime. But how can the circles around each other around a center of gravity midway between them where there is no substance mass is to create the recess both substance masses after Einstein's view, the circles on the edge of?

Spacetime does not exist as a property of space, why gravity is a force like the electric and the magnetic force and possibly may even interact with them.
AmritSorli
1 / 5 (6) May 11, 2011
exactly, mass increases density of quantum vacuum and this generates gravity, time is not part of space, time we measure with clocks is an epiphenomena of material change, i.e motion, time is a numerical order of material change

Two identical substance masses orbiting each other, after Einstein's view, each creating an indentation in spacetime. But how can the circles around each other around a center of gravity midway between them where there is no substance mass is to create the recess both substance masses after Einstein's view, the circles on the edge of?

Spacetime does not exist as a property of space, why gravity is a force like the electric and the magnetic force and possibly may even interact with them.

AmritSorli
1 / 5 (5) May 11, 2011
Time is an epiphenomenon of change

Change is the fundamental property of material world. Time that we measure with clocks is the numerical order of change, i.e. motion in space. In physical world time exists as the numerical order of change in space. In physics time is a mathematical dimension used for description of change in material world. It is an utter misunderstanding to think time is part of space and change run in time. On the contrary: time is an epiphenomena of change, time we measure with clocks is the numerical order of change.
AmritSorli
1 / 5 (5) May 11, 2011
Geodetic precession and Frame dragging precession are measured in a 3D space in which satellite move. This is a prove that universal space is 3D. Time is definitely not dimension of space. Time is the numerical order of satellite motion.
In physics time is a mathematical dimension for description of satellite motion in space, but we have to be aware satellite moves in space only.
ubavontuba
1.7 / 5 (6) May 11, 2011
3D space can also be curved
Really? How?

Perhaps you mean a 2D space can be curved into a third dimension?

A 3D space, being curved, implies a fourth dimension.

AmritSorli
1.8 / 5 (5) May 12, 2011
not at all.....Riemann geometry can have also 3D formulation

3D space can also be curved
Really? How?

Perhaps you mean a 2D space can be curved into a third dimension?

A 3D space, being curved, implies a fourth dimension.


ubavontuba
1 / 5 (2) May 12, 2011
not at all.....Riemann geometry can have also 3D formulation
Of course, when you're talking about geodesics on a 2D surface which imply a third dimension. But that isn't 3D space + time.

"Any smooth manifold admits a Riemannian metric, which often helps to solve problems of differential topology. It also serves as an entry level for the more complicated structure of pseudo-Riemannian manifolds, which (in four dimensions) are the main objects of the theory of general relativity."

http://en.wikiped...geometry
AmritSorli
1 / 5 (3) May 12, 2011
when you measure angles between 3 points in space and sum is 180 degree, space is flat, if sum is more or less than 180 degree, space is curved
Ethelred
3.9 / 5 (7) May 13, 2011
And the curvature must be in another dimension. In GR that is SPACE-TIME and since the theory works there really isn't a reason to try to make one dimension go away by huffing and puffing and holding your breath til your face turns blue.

Show evidence that supports YOU. This evidence supports GR which has FOUR dimensions.

Ethelred
AmritSorli
1 / 5 (6) May 13, 2011
yes GR has 4 dimensions, but comnic space has 3, Experimental data of Gravity Probe B does not give any evidence that stellar objects move in time as a 4th dimension of space. On presented facts it is plausible to challenge the concept time being 4th dimension of space. Duration of material change, i.e. motion takes place only in a 3D space and not in time. Time we measure with clocks is the numerical order of duration of a given physical phenomena in a 3D space. In physics 4D space-time is a mathematical model used for description of change in 3D material world; we have to be aware clocks tick in space only, not in time, elementary particles and material objects move in space only, not in time. It is an utter misunderstanding to think in the material world time is a 4th dimension of space and material change run in time. On the contrary: time we measure with clocks is merely the numerical order of material change, i.e. motion in a 3 dimensional universal space.

ubavontuba
2.8 / 5 (9) May 14, 2011
Gravity Probe B does not give any evidence that stellar objects move in time as a 4th dimension of space.
You are such an idiot. As it confirms predictions of GR, it verifies spacetime. Do you have any experiment that contradicts GR? No? Then shut up.

Jeez. I think AmritSorli would argue that time is slower for a frozen chicken as opposed to a room temperature chicken, even though neither will make a clock run slower relative to any observer! I can hear him now... "The numerical order of change for the frozen chicken is slower, therefore time is slower for the frozen chicken. This is true because I say so."

What a buffoon.