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'Einstein Probe' Delayed
isorox writes "The BBC is reporting that a NASA satellite designed to test frame dragging, predicted by the theory of relativity, has been delayed for 24 hours because mission control couldn't verify the correct software had been loaded. The probe was proposed 35 years ago, but has never had the funding until now. The question remains is what happens if Frame Dragging isn't observed - will the experiment be wrong (in other words there's no point to it), or will we get faster-than-light ships for Christmas?"
-- johntracy.com, because everybody else is wrong.
I'm voting for warp drive on this one!
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because mission control couldn't verify the correct software had been loaded.
Man, I must have missed a career as NASA flight controller, because I feel exactly the same way each time XP goes to windowsupdate.microsoft.com...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
The question remains is what happens if Frame Dragging isn't observed - will the experiment be wrong (in other words there's no point to it),
Then you have a Type II error, methinks. It's not that you are wrong outright (like a Type I error. You've just missed the chance to reject the null hypothesis correctly was munged. Refine. Try again.
Comparing it to Windows will be a moot point, since El Dorado is going to have a 40% larger code base than XP.
by British scientists!
--- You shall know the truth, and the truth shall make you mad- Neal (not Cowboy) Boortz
Whenever I try to run games at too high resolution on this computer, the frames just start dragging along...
you dumbass .. that's like saying Newton was wasting his time coming up with his theories .. I mean who knew there'd be any practical applications of figuring out the laws of physics?
They had built the pyramids and horse & buggy just fine without Newton.
Frankly, I hope they find that einstein was wrong and that there is a way to easily "bend" what we observe in the curvature of space time.
Imagine a warp bubble rendering the contents essentially massless, thus the input energy for kinetic motion is miniscule enabling fantastic speeds.
However if they are right, that might mean that general relativity rules and we are forced to live by it's law (It's still a theory, will this make it a law?). How unfortunate.
Never let your sense of morals prevent you from doing what's right. --Isaac Asimov
Man, stop smokin the crack:
1) Good result, but result appears to confirm the prediction - this is a successful experiment - a negative result is as valid as a positive one.
1) Good result, and result appears to confirm the prediction - this is a successful experiment
That says the same freaking thing!! Not to mention you started at 1, went to 2, and then did 2 more 1's just trying to get to "four posibilities."
The question remains is what happens if Frame Dragging isn't observed - will the experiment be wrong (in other words there's no point to it), or will we get faster-than-light ships for Christmas?
:)
Let me put it this way:
Greetings from next Tuesday!
As a classically trained scientist, I'd be loathe not to point out a misconception here.
Experiments themselves are never 'wrong' experiments are merely poorly designed or interpreted. If they are niether of these then the experiment simply gives you data which you must explain. If it doesnt give you the expected results, it may not be the design that is in error, but instead our understanding of the world.
Data never lies, except when viewed through a human bias.
Surely you mean:
1) Bad result, but result appears to confirm the prediction - this is not a successful experiment
2) Bad result, but result appears to invalidate the prediction - this is not a successful experiment. Possibility of an insufficiently sensitive instrument, or just a badly designed experiment.
3) Good result, but result appears to contradict the prediction - this is a successful experiment - a negative result is as valid as a positive one.
4) Good result, and result appears to confirm the prediction - this is a successful experiment
I am artificially intelligent.
Except that the general theory of relativity was created because newtonian gravity violated the speed of light. If this test showed that frame dragging did not exist, we would be have to figure out a new way of making those two consistant, and (on the surface at least) one (unlikely) possibility would be that some things can travel faster than light.
The aliens invented the horse and buggy?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I've read that frame dragging had already been reported in astronomical observations, and that this is expected to be an important but unsurprising laboratory confirmation of the phenomenon.
I guess one could accuse certain modern physicists of coming up with "theories that fit reality". But we should remember that Einstein came up with his theories when most of them could not have been possibly proven correct or wrong, so there are at least some theories there, that are not after the fact descriptors of reality but true predictors of the behaviour of the universe.
As far as the usefulness of this, it is also usefull to know how the world around you works. Take nuclear physics -- i am sure people would have characterized the early experiments with radium as pointless, but now the long term future of humanity depends on nuclear energy. The ultimate destruction of humanity also depends on nuclear energy. So whether you are pro or anti humans, nuclear energy is your best bet!!!
In this case its called "foot dragging", not "frame dragging".
Table-ized A.I.
The question remains is what happens if Frame Dragging isn't observed
You can listen to John Turneaure, co principle investigator for Gravity Probe B. He was interviewed by Ira Flatow on NPR's Science Friday.
When Ira Flatow asked him what would happen if the probe did not find anything and that Einstein might be wrong, he "hemmed and hawwed" a lot and said that wouldn't be the case - that Einstein was right. He also mentioned that the data would go to a physicist and then be released to the public.
It's not that I'm wearing a tin-foil hat (well maybe), but science is based on conducting experiments in the open and openly sharing data with an unbiased view and procedure, even if it means that Einstein might be wrong.
If they really wanted to do this neat, they would stream the data live to a website, rather than can up the data until they are ready to release it.
There are critics of Einstein that are academically serious and not off their rocker like some zero point/tesla fanatics. There have been critics of Einstein ever since he released his theories. You don't hear much about them as they are all heaped into one group and astrocized.
I am not saying that Einstein was wrong (not in the sense that Newton was wrong either), but that true science is keeping an open mind, rather than cower to the politically favorable theory of the moment.
As an aside, frame dragging is like when you take a single electric mixer and use it in a bowl of pudding. Or when you use an electric stirrer in a can of paint. That is frame dragging.
This happens because gravity is a field (according to Einstein). Newton treated gravity like a force.
Physicists reading may improve upon this anology.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
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"...test frame dragging, predicted by the theory of relativity... will we get faster-than-light ships for Christmas?"
What does frame dragging have to do with faster-than-light?? The wikipedia link mentions nothing about how frame dragging has to do with faster-then-light, so I searched google and found this article on msn:
"Spinning black holes may pull in gaseous matter from their sister stars as a rapidly rotating "accretion disk," analogous to water circling down a bathtub drain.
The American scientists built on their previous research into the mass and spin of black holes to look for signs of space-time distortion, or frame-dragging.
In Einsteinian physics, the space-time continuum is often compared to a sheet of rubber. Mass creates a gravitational "dimple" in that space-time sheet. But a rotating object -- like a spinning black hole -- adds an extra twist to the dimple. Matter caught in that twist would appear to wobble in orbit around the object, like a toy top wobbling on its axis.
Cui explained that travelers passing close to a black hole would feel as if "nothing happened." But a distant observer would see the travelers being dragged around the black hole."
my karma will be here long after I'm gone
To observe time warping, they will launch a probe into space with balls in vacuum flasks frozen to near absolute zero 400 miles above the earth. They are making it hard. There is really nothing to time warping.
It's just a jump to the left
And then a step to the right
Put your hands on your hips
And bring your knees in tight
And it's the pelvic thrust that really makes you insane
Let's do the time warp again!
Let's do the time warp again!
How ya like dat?
The question remains is what happens if Frame Dragging isn't observed.
Then they'd better figure out if their experiment was badly designed, because frame dragging has already been observed by other research platforms.
NASA's Rossi X-Ray Timing Explorer observed frame dragging in a distant system consisting of a binary pair of black holes. This was back in 1997.
Analysis of the motion of two earth-orbiting satellites, LAGEOS I and LAGEOS II, also reveals frame dragging going on. This was also over 4 years ago, and it's the result that this Einstein probe is supposed to refine.
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Building a ship to go faster than the *speed* of light is (relatively, ha ha) easy. Building a ship to *pass* light is difficult. No matter how fast you chase after that light (even if you cross the universe in seconds!), it will always remain 300,000 km/sec faster than you are! And if you do manage to reach light speed (good luck) you'll be just as frozen in time as photons are. In other words, you'll get to travel the universe, but you'll never know that you did it.
Of couse, the only way we know we're travelling "faster than the speed of light" is that we can measure the time between our point of origin and our point of destination. Time dilation makes sure that we're never able to pass light. If there was nothing else in the universe but your ship and light, you'd have no way of knowing that you were moving! How annoying is that?
Javascript + Nintendo DSi = DSiCade
If this test showed that frame dragging did not exist, we would be have to figure out a new way of making those two consistant, and (on the surface at least) one (unlikely) possibility would be that some things can travel faster than light.
Why do you humans always misquote Einstein. General relativity states that nothing can *accelerate* to the speed of light. It says nothing about things already going the speed of light. Experiments in Photon / Quantium Tunneling have indicated that photons can apear to tunnel through barriers faster then light.
Doesn't the emission of entangled-quanta already violate thee speed of light? I believe this was tested in the Aspect Experiment.
Also, I just took a course in the philosophy of physics but the one thing I never understood was how anything going was than the seepd of light would ruin Einstein's theory? If another THING was found that was faster as light and had the same speed in all inertial frames wouldn't that be sufficient? You could have THING-cones (where volume(THING-cone) > volume(Light-cone)at any time T --by volume I mean the fourth-dimensional equivalent), and things that are currently space-like seperated could be reclassifed as THING-like(for things faster than light but slower than THING) or space-like seperated (faster than THING), and this could account for the Aspect results. It also wouldn't need to violate the rule of not travelling faster than the speed of light since it could be mass-less and then as it approach and crossed C it mass would still be zero as opposed to approaching infinity.
IANAPhyisicist but IAALPhilosopher
Your CPU is not doing anything else, at least do something.
Unfortunately, black holes are sparse in this neck of the woods
_UN_fortunately?
Ground controllers could not verify the rocket had all its correct flight software loaded, and halted the launch.
I bet they're wishing now they'd kept the About box in the spec.
> > Unfortunately, black holes are sparse in this neck of the woods
:)
> _UN_fortunately?
Well, in most necks of the woods they're actually rather dense.
HOO-ha!
---- I'll take you in a Hunt deathmatch any day.
No matter, energy, or information is propagated faster than light in quantum entanglement.
Einstein's theory itself doesn't forbid something from going faster than light. (However, there are problems with FTL objects and causality, such as observers for which effects take place before causes, and tachyons also destablize the vacuum in quantum field theory.) It does forbid objects from crossing the c barrier (which would require infinite energy).
In a theory with Lorentz symmetry (i.e., relativity), there is only one invariant speed: the speed of light. There can't be another speed (faster or slower than c) that is invariant in all inertial frames.
In relativity, massless objects can travel at only one speed (c), neither faster nor slower.
Why do you humans always misquote Einstein.
:-)
Because schools nail silly ideas into people heads, and Einsteins book "Relativity: An Explaination That Anyone Can Understand" wasn't so easy to understand?
General relativity states that nothing can *accelerate* to the speed of light.
Err... I thought that was Special Relativity. General Relativity deals with the way that gravity works. i.e. Gravity is acceleration. Therefore, matter and energy must curve space-time to make a "downward" slope.
That being said, you have the "halfway" problem of accelerating to light speed. As you accelerate, time dilation increases. As time dilation increases, your engines are less effective to an external observer. Therefore it becomes a lot like drawing a line halfway to the destination, then drawing another line halfway of the remainder, ad infinitum. You'll never reach the end. And because your mass increases, you could only use a rocket (converts your near infinite mass -> energy) to make the transition. An external force like a particle accelerator doesn't have enough energy (infinite) to push you to light speed.
It says nothing about things already going the speed of light.
Correct. When a collegue of Einstein's suggested that it was impossible for an object with mass to reach light speed, Einstein felt compelled to point out that a photon has mass and it travels at light speed.
Experiments in Photon / Quantium Tunneling have indicated that photons can apear to tunnel through barriers faster then light.
That really has more to do with Quantum Mechanics than relativity. Overall, the photon is incapable of exceeding light speed. However, it can temporarily "steal" a bit of energy from nearby particles to tunnel out of existance and into existance elsewhere. The amount stolen is then payed back, resulting in a zero sum gain in velocity.
There are many things in this universe that appear to defy light speed. Unfortunately, not one of them is capable of transmitting useful information faster than light. Considering that this holds true at all levels of physics, one would almost conclude that the universe is out to "get" us.
Javascript + Nintendo DSi = DSiCade
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Disclaimer - I worked on the Gravity Probe B (GPB) team back in 1994-1995 while I was an undergraduate at Stanford. Due to personal interest, I watched the launch attempt on NASA TV.
While technically correct, the post's claim that the lauch was delayed "because mission control couldn't verify the correct software had been loaded" doesn't convey the whole picture of what happened.
Well prior to T minus 4 minutes, three weather balloons had reported excessive (out of limits) high altitude wind shear. This wind shear would have caused the launch to be delayed for 24 hours.
However, shortly after T minus 4 minutes, a fourth weather balloon reported that windshear had dropped to within acceptable limits. At this time, the flight profile of the delta II rocket needed to be updated to successfully guide the rocket through the high altitude wind shear and in to GPB's desired orbit.
The launch window for GPB is very narrow - about one second. This is because GPB needs to be in a polar orbit in the plane of a particular guide star.
A launch director from Boeing (Boeing made the delta II rocket) could not confirm that the flight profile had been successfully updated. So, with the clock counting down, he made the decision to "hold" the launch. Upon review, all the launch directors agreed that this was the correct decision.
So, you have a situation where, under time pressure, about 300 seconds before launch, due to changing launch conditions and unverifyable equipment status, a conservative and correct decision was made to delay the lanch 24 hours - until the next one second long launch window.
The other thing to consider is that the closer you get to launch, the more costly and complicated it is to abort the launch. So even though confirmation of a successful profile upload may have come later, if it hadn't, the costs of scrubbing the launch would be higher.
While it may be fun to bash NASA, just remember that it really is rocket science, at least in this case.
He still cannot accelerate to or past the speed of light. If he were enclosed in a box traveling at a constant velocity => lightspeed, then yes everything would appear normal to him, and it's only the stationary observer who would notice anything odd. However, assume that same box is ACCELERATING to lightspeed, and suddenly the man in the box is exposed to all of the effects that entails. Namely, mass going to infinity, and energy required to continue acceleration going to infinity.
.... But the more massive an object is, the harder it is to increase its speed. .... Since a the mass of a muon increases without limit as its speed approaches that of light, it would require a push with an infinite amount of energy to reach or to cross the light barrier. This, of course, is impossible and hence absolutely nothing can travel faster than the speed of light."
Let me dig up a reference...
The Elegant Universe, by Brian Greene, PhD (from Oxford)
Page 52
"You may have wondered, for instance, why6 we can't take some object, a muon say, that an accelerator has boosted up to 667 million miles per hour -- 99.5 percent of light speed -- and "push it a bit harder," getting it to 99.9 percent of light speed, and then "really push it harder" impelling it to cross the light speed barrier. Einstein's formula explains why such efforts will never succeed. The faster something moves the more energy it has and from Einstein's formula we see that the more energy something has the more massive it becomes. Muons traveling at 99.9 percent of light speed, for example, weigh a lot more than their stationary cousins. In fact, they are about 22 times as heavy -- literally.
Where to Publish Your Paper
- If you understand it and can prove it, then send it to a journal of mathematics.
- If you understand it, but can't prove it, then send it to a physics journal.
- If you can't understand it, but can prove it, then send it to an economics journal.
- If you can neither understand it nor prove it, then send it to a psychology journal.
- If it attempts to make something important out of something trivial, then send it to a journal of education.
- If it attempts to make something trivial out of some-thing important, send it to a journal of metaphysics.
I'm sure folks can add a few items suitable to this conversation and Slashdot."It is a greater offense to steal men's labor, than their clothes"
Not really. The main motivation for the general theory was simply that Newtonian gravity (or more specifically, the Newtonian gravitational potential) failed to make predictions which agreed with observation. The most well-known example of this is the precession of perihelion of Mercury. If you're referring to the fact that Newtonian gravity imposes no upper bound on velocities, then you're correct, but this was more an illustration of the fact that Newtonian gravity was largely irreconcilable with special relativity.
Nope. I am afraid that the parent was correct and that you may have misunderstood him.
Einstein's motivation for GR (General Relativity) was that SR (Special Relativity) is inconsistant with NG (Newtonian Gravity). NG does indeed predict faster than light effects. If you wiggle a particle on one side of the galaxy, then a particle on the other side would feel that immediately.
This is a theoretical motivation, and not a physical motivation. Once you have SR, you immediately have to fiddle with gravity. He would have had to do this even if we had no conflicting evidence against NG.
A Usenet Troll Triumphs on Slashdot
I was actually just talking to my advisor about this (astronomy chair) and the basic idea is this: the scientific communtiy has been killing this project constantly (he several times graphically depicted shooting something on the ground) just to have someone in congress decide to bring it back. It's the most illconceived experiment - they are trying to measure not only what has been completely PROVEN but also in the most inane manner. Just about everything else that affects the gyroscopes are larger effects, what they are trying to detect is so small. When this was first thought up, it was probably kind of novel, but we're beyond that (can you say strings) now and its just one messey experiment (would you want to do the math for that?).
So why not work on something useful like alternate propulsion systems or batteries that keep my mp3's coming for more than 10 hours....
When Kepler figured out the planetary orbits, he envisioned invisible brooms sweeping the planets towards the sun. When I read "gravity is just curved spacetime" I think of Kepler's brooms as they both seem to say about as much.
:-)
Think more like a bowling ball on a trampoline. The bowling ball will "warp" the trampoline, and objects placed on the trampoline will fall toward it.
As for planetary motion, I'm sure you've seen those funnels that you put coins in. The coin spins round and round. Friction eventually slows it down enough to fall toward the center. If your coin was in a vacuum and had sufficient velocity, it could keep going around the center forever. (e.g. The Earth keeps "missing" the Sun)
Just how does mass warp space? How does space know the mass is around?
We don't know the former yet. Space knows mass is around, because at a quantum level matter and energy are inbalances in the vacuum. "Empty" space is really a bunch of wild waves called "quantum foam" that all cancel each other out.
What particle is gravity's carrier?
Gravitons are only theoretical. At this point it looks like they don't exist. In other words, gravity waves are perpetrated in a vacuum instead of by a particle like the strong force's gluon.
If there is a gravity particle, how come planets don't speed up as they plow into them orbiting the sun?
If a planet heads toward the Sun (not a good thing) it *will* speed up. The trick is that a stable orbit implies having *just enough* speed to keep missing the object.
And how come it gets to escape black holes but no other particles can come out and play?
Because there's no particle. It's the nature of space-time.
We can describe gravity's effects but we can't say how it does the trick.
General Relativity says gravity == acceleration. Therefore, the presence of matter and energy "slopes" space-time in such a way as to accelerate all other particles in the Universe.
Javascript + Nintendo DSi = DSiCade
Ken Thomposn built Gravity B as a constrained version of Gravity BCPL. Once K&R got their hands on the technology and added a type system, they were ready to launch Gravity C. Gravity C++ soon followed in an attempt to incorporate Quantum Mechanics.
/. articles, there is much talk about Gravity D; hopefully it will have some nice black-hole garbage collection.
A perfect SuperString implementation has yet to be added to the language, although many incompatable approximations exist.
As we know from recent
Gravitons are only theoretical. At this point it looks like they don't exist.
Actually, according to String Theory, they're very real.
ST's use of them is really interesting - there's always been kind of a mystery as to why gravity is so weak compared to the other forces. ST says that the strong/weak forces and electromagnetism have carrier particles whose strings are anchored to our brane in the bulk*. It goes on to say that gravitons' strings are free-floating, so they are not bound to our brane. This would mean that when a source of gravity was present, much of it was leaking out of our brane, leaving behind the relatively weak force we feel instead.
Apparently something that is being looked forward to with the Large Hadron Collider is that they might be able to see evidence of a graviton escaping from our brane.
* For those who aren't familiar with these concepts, ST includes the idea that our 3+1 dimensional universe (3 spatial, plus time) is only one "slice" of an extradimensional body called "the bulk." The "slice" is referred to as a "brane." If String Theory is right, there are other branes millimetres away from us, but in a higher spatial dimension. The only theoretical way to communicate between them is with a graviton-generating device.
Incidentally, Alastair Reynolds makes use of this concept in his latest novel, Absolution Gap. There are some quotes from his books in my journal if anyone is interested.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
This aired last Friday on public radio:
Talk Of The Nation Science Friday
Seek to 27:30 for the start of the audio program on Frame Dragging.
To blog is sublime
We can describe gravity's effects but we can't say how it does the trick.
I think that sums science up: you always have to say "nature behaves AS IF it were this way"; we can see the hands on the watch go round but we cannot open the case (Einstein).