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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.
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.'"
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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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.
Unfortunately, black holes are sparse in this neck of the woods
_UN_fortunately?
> > 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....
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