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Einstein's Theory To Go Beta Testing
pinqkandi writes: "This article over at CNN looks into the relativity of Einstein's theory of relativity (pun intended) as equipment becomes more and more precise. Soon atomic clocks will be placed in the International Space Station to analyze the accuracy of Einstein's theories. One of the lead researchers says that if Einstein's theory is not right, it will only need minor adjustments to account for changes in space-time, due to its deadly accurate precision."
--- I'll have a Bloody Mary, a Steak Sandwich and a uh Steak Sandwich.
Well, it has been said for years that Relativity and Quantum Mechanics can not both be true without some deeper explanation (i.e. Supersymmetry or String theory). Perhaps this experiment will be the tie-breaker to tell us which is MORE right.
If you don't understand either one, take a look
here:
Hasn't this been proved already? What's wrong with those older proofs? Like the atomic clock in the airplane and GPS satellites?
Deadly precision? What has space-time done to you lately?
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I remember in the seventies they got two atomic clocks and stuck one on a plane and after two years of the plane flying around aimlessly they found a minute difference
in time.
The joke of it all is that after a year some journalist asked why they didn't just stick it on a regular commercial jet but they didn't think of it at the time.
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While we might think that we are equipped to carry out the beta test on Einstein's theory, methinks we may not yet be ready.
Practically, what we understand from the Theory of Relativity is what we BELIEVE we understand, and that will influence what type of outcome we are searching for.
Plus, the equipments that we think are ready may not be ready.
Take the Atomic Clocks for instant
After all, the "ticks" of the atomic clock, no matter which type of "atoms" we base it on, still depends on the variable TIME - as "ticks per second".
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is here, with a little more information on Lorentz and CPT violation.
As a born pedant, when asked the question "What's the time?"
:D
My typical response is:
"An abstract system that allows one to distinguish sequences of events"
I then laugh till I puke
If nature abhors a vacuum, why isn't there more dust in the world?
Maybe it's just the way the guy was quoted in the article, but if they need to test in a "zero gravity" environment, how would the ISS be applicable?
I'd consider it a "weightless" environment, but not "zero gravity".
- Tony
AFAIK the current GPS satelite system makek adjustments for relativity in the signals it is sending around and they have been adjusting for this for years. See the articles at Metaresearch and lsu.edu for more info.
Soon accurate telescopes will be installed to make extremely careful measurements of Mercury's orbit to analyze the accuracy of Newton's theories. One of the lead researchers says that if Newton's theory is not right, it will only need minor adjustments, due to its deadly accurate precision.
Real Daleks don't climb stairs - they level the building.
Even as a joke this makes no sense. Relativity was alpha tested in the 1913 (IIRC) eclipse and has been tested very very thoroughly since then. This is just another fine-grained test.
The universe IS a beta test for relativity.
Einstein's special relativity was just an advanced features appendix to be added to the manual.
Like, they put one of those into an airplane and flew it half around the globe or something.. That might have been another aspect of the theory though.
But one thing is for sure: They won't 'prove' Einstein in any way by doing this - but they might *prove* him wrong. Only negative proof can be done by example.
Love over Gold.
Too bad Einstein isn't around anymore...
He would have made for one heck of a great match on Fox Celebrity Boxing 3 with Stephen Hawking.
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Can a clock really be DEADLY accurate? A rifle, a smart bomb, maybe even a rolling pin weilded by an angry wife when her husband comes in late.... THESE can be deadly accurate... I don't think a clock can be.
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The CNN article is not very clear as to what it says. This comes from the fact that There are two different theorys of relativity.
1 The special theory
2 the General theory.
The special theory concerns what happens to the laws of physics as a person is traveling at a constant velocity, whereas the general theory is concerned with bodys that are accelerating ( In general relativity acceleration and gravity are equivalent).
So since the ISS is in orbit it experences an outwards accerleration( the same as one experences as one goes round a corner fast in a car.) In space there is gravity on the ISS but it is very little. This means that the ISS will experence a slight change in the ticking rate that is recorded. But this is explained by the general theory of relativity and not the special theory.
My friend... clocks can be VERY dangerous indeed. (and never mix clock usage with high BAC, that is just asking for trouble) Chronology and fermentology never make good bed buddies.
"If variations in the ticking rate were discovered, Kostelecky says, it would be a "striking signal" that the laws of nature may be based on fundamental theories other than Special Relativity -- or perhaps in addition to it."
I thought this was precisely what special relativity does predict, that a moving observer experiences less passage of time than a stationary one, increasingly so as the speed becomes a significant fraction of the speed of light. If the ticking rate does not vary, then special relativity would be invalidated.
-- Adam
Probably this won't be so much beta-testing relativity as it is verifying the anti-relativists.
Karma: Bored. (Thinking about resurrecting the "Anyone else is an imposter" joke.)
This just in, from a 1903 Einstein press release:
One of Einstein's lead researchers says that if Newton's theory is not right, it will only need minor adjustments to account for changes in space and possibly time, due to our upcoming theory's deadly accurate precision.
Not that Salon is a peer-reviewed journal or anything, but this will give a little background for those who'd like it. http://www.salon.com/people/feature/2000/07/06/ein stein/
Karma: Bored. (Thinking about resurrecting the "Anyone else is an imposter" joke.)
NOW! Brand new on the Market: MS Relativitiy (future patches coming soon!)
gah, it turns out it was only slightly related... like a third cousin.
(smack me, i know it's an obvious joke)
I can't believe it's not lard!
This is an honest question. Most theories I know of have things they cannot account for, but I have not heard where relativity fails.
What is wrong with using existing equipment, like that hive of atomic clocks in the GPS system? They already transmit their time to just anybody that wants to receive it and all of the adjustments for relativity, etc., are known and can be removed for "raw" time measurement.
I guess the hammer and feather experiment just gets more expensive in proportion to the expansion of the beurocracy.
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That's my bet.
Be cause I can't see, what happens with a circular train around the Earth. How does it shrink, when it's velocity approaches c?
And this inconsistency must pop out on some other places as well. Sooner or later.
- Thomas
Atomic clocks on ISS are a trivial test of relativity compared to Gravity Probe B, hopefully to be launched soon after DECADES of development. A one-pager "GPB for Dummies" is here. GPB tests not for alterations in time but another phenomenon known as "frame dragging" which has never been directly measured. There's been lots of criticism about GPB as being too ambitious, so there's been lots of independent reviews.
These tests might be more interesting on a craft traveling deeper into space. Maybe the next Mars mission? You might see greater inconsistancies.
Can I bum a sig?
Either this is a totally narcistic sense of time, or else this requies certain metaconditions, such as an immortal soul (or similar) with the ability to be unconscious. There could be the ability to connect/disconnect from various time streams, etc. But this goes into discussions that many folks find uncomfortable. And most such subject definitions of time do not try to integrate these other factors.
[shrug]
"It is a greater offense to steal men's labor, than their clothes"
An article (membership requires) in May Physics Today details the extensive corrections GPS must make for both special relativity (velocity corrections) and general relativity (gravity corrections). This has tested Einstein every day of the past 20 years, and he has held up.
So there planing to space-time using radioactive decay by increasing the potentinal of the decaying isotopes. hmmm.... prohaps they should try other 'artifacts'
All that will prove is that radioactive decay is relitive to the kenetic potential.
thank God the internet isn't a human right.
I heard GPS sattelites use atomic clocks to keep in synch with earth. They use the Theory of Relativity to adjust their times so that they stay in synch with earth because they move at a different speeds and in a different field of gravity.
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A play on words, sometimes on different senses of the same word and sometimes on the similar sense or sound of different words and they need a hefty bit of setting up, like a large story resulting in the punch line "I don't know for whom the Tell's bowl"
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Time doesn't exist, depending on how you look at the situation. I don't know that your interpretation has been proven, though it has some merit. Isn't time technically a fourth dimension, t ? The question should really be, is "time" a by-product of movement in space, or is movement in space possible because time already exists?
I wonder if Scientists ever play practical jokes on each other and sneak into the lab to make the Atomic Clock blink 12:00
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As far as velocity is concerned, we currently do adjustments to the GPS clocks every time we do a delta-V (thruster fire), even a small one. Because we deliver accurate timing to the near Nanosecond level, we must use relativity adjustments with every change in velocity or it tends to be mismodeled by the Kalman Filter.
As far as clock attitude vs the earth's gravitational field it seems as if we could post process that info, and it would be a semi-interesting study.
Just my 2 cents.
As I recall, it was proven wrong by the detection and acknowledged existence of Tachyon particles travelling at over the speed of light when detected...
References? I somehow missed the scientific article on the detection of tachyons.
If you really want to test the theory, build an ion engined probe with small nuclear battery and atomic clock, transmitters, etc... and enough fule to acclerate to relativistic speeds.
Oh, I'd love to, but I have to mow the lawn tomorrow, maybe I'll get to it next week. Um, don't you think if we could do that, we'd find something better to do with it than test relativity... say, fly to Mars?
The theory has to be wrong because we have observed multiple instances of the violation of conservation of energy and the hard and fast rules around C speeds.
And I assume you have some references here as well?
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Thank you for your views from the future!! Exactly when were FTL Tachyons detected and acknowleged?
They already have quite accurate measurements on the effect of relativity on reference frames moving at different speeds and at different potentials in a gravity well. They are dead on, so far. For example, the GPS system (which uses atomic clocks generating signals to locate where you are) needs to have its clocks reset periodically because they get out of sync with ground clocks. I'm sure there is more than enough literature on this part of the theory for anyone to be happy. The only place where i would begin to question it is when you are dealing with an extreme difference in gravity (not on the velocity side, that has already been tested). I suppose (since it is a MODEL after all, just an extremely good one) that when gravity is very large other terms might begin to show themselves, if they do exist.
Tachyons are hypothesized to travel faster than the speed of light. It's a common misconception that Einstein's theories prohibit FTL travel - they do not. They do prohibit massive particles from accelerating past the speed of light (would require infinite energy). Massless particles like photons and the theoretical tachyon don't have this problem.
I thought Tachyons were a prediction, not experimentally verified? You are right that there are a few inconsistencies with GR though, mainly with Quantum Physics. -s
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people find that it helps to toss all logic out of the window to accept quantum physics too. it's only a matter of 'time' ;) that scientists come to the same conclusion about time :)
whereas the general theory is concerned with bodys that are accelerating ( In general relativity acceleration and gravity are equivalent).
Common misconception. Acceleration and gravity are not equivalent in General Relativity. They are *locally* (that word is extremely significant here) indistinguishable. The fact of the matter is that Special Relativity can handle acceleration just fine by using calculus. General Relativity is only needed where spacetime is not flat (i.e. in the presence of gravity), since the two postulates of Special Relativity only hold in regions of flat spacetime.
A detail that I left out of my previous post is that Kostelecky and co-workers have developed a framework describing a very general set of extensions to the standard model which violate Lorentz invariance. You can find out more about this set of extensions at his website and in the papers referenced there. His framework (which I don't understand in the detail which I should) includes a set of parameters (whose values must be determined by experiment) which are Lorentz invariant in some underlying high energy theory but lead to CPT and Lorentz violations in the low energy limit (where the low energy limit includes everything from atomic clocks to the highest energy accelerators).
It turns out, however, that a standard atomic clock such as those used in the GPS satellites is not sensitive to these effects. In the measurements Kostelecky is talking about and the measurements we have done on the ground, one looks not at the standard clock frequency (based on the hyperfine transition) but instead at an auxillary frequency (a Zeeman transition) which has a first order magnetic field dependence. This frequency is sensitive (in leading order at low magnetic fields ) to the effects Kostelecky's framework predicts.
Therefore, one needs to operate an atomic clock in a slightly unusual way to search for these effects. In the hydrogen maser measurements we have performed (the Phys. Rev. D paper I mentioned) we measure the standard clock frequency while "tickling" the Zeeman frequency and record the shifts. A similar technique is being proposed in space. I wouldn't think that such a technique would be realistic on the functioning GPS satellites.
they got two atomic clocks and stuck one on a plane and after two years of the plane flying around aimlessly they found a minute difference
I've heard of this experiment, but I have a serious question about it that's always bothered me.
This assumes that Clock A is stationary at 0 mph and Clock B is traveling at 400 mph, right? But, given that the Earth rotates AND orbits the Sun that assumption isn't really true. Relative to a given point, sometimes they're going faster and other times slower. Also, since Clock B is ideally flying in a big circle (around the Earth) doesn't its velocity (in relation to a set point) average out to 0 as well?
I would think that this experiment would only work if Clock A was dropped off somewhere in space and Clock B was launched in a straight line relative to Clock A. Where am I wrong?
I do believe when I was in university I was taught it was always prudent to verify the "worthiness" of a source before one references to it in their paper.
:-)
I think I remember CNN and other mainstream media sources fallen under the "instant rejection" class of grading.
Am I wrong? Have times changed?
heh.... unintentional pun... cool
My mom always said, "Jim, you're 1 in a million." Given the current population, there are 7000 of me. God help us all!
I wonder if Scientists ever play practical jokes on each other and sneak into the lab to make the Atomic Clock blink 12:00
I just got a flash of Professor Frink walking into the lab, "Oh, for crying out glavin..."
But I do believe in uncertainty.
Does this mean my GPS will stop working now?
:)
There are actually two different effects that can cause one observer's time to move faster than anothers:
1) From special relativity, if the observers are moving relative to each other, _each_ will see the other's clock as moving slower than theirs. This causes the twin paradox, which ends up being resolved by...
2) From general relativity, if an observer is "accelerating", their clock moves slower relative to a non-accelerating observer. Note that in GR, staying stationary in a gravitational field is actually "accelerating": You can't distinguish between sitting in an elevator that is in free-fall and an elevator that is floating in space, or between an elevator that is sitting still in the earth's gravity and one that is accelerating upward while in space.
The effect that causes the atomic clocks to show different times is the latter: one plane is 30K feet higher than the other, so assuming that it doesn't do a lot of stopping and starting or high-G turning, its average acceleration is less.
...with or without the robotic exoskeleton?
As an American, I can still say that we are most definitely not the best in all of those areas. The American Public School System is deteriorating and doesn't teach nearly as much as those of other countries. Economically we do well, due in large part to screwing over other countries. Politically - in two words - George Bush.
However, American colleges help catch us up to the rest of the world..and public schools do allow free thought, socializing, and allow for creativity - unlike schools in many parts of the world. America is still a great place to live after balancing out the positives and negatives, but I would hardly start ranting about us kicking the worlds ass just yet.
The article on CNN's "Tech" page was poorly written and showed little understanding of the process of science or of physics. The Theories of Relativity are just that--theories. They are subject to modification as new empirical experimentation provides data that either confirms the theories or shows their defects. The experiments on the space station may show that the theories need to be modified, but the writer (Eleni Berger) sensationalized the whole process and writes as if they will cause the theories to be thrown out entirely. Can't a large organization like CNN afford to find a writer for its science articles that has a basic understanding of what he or she is writing about?
The GPS satellites are not geosynchonous. They actual hurl through the sky at a qhick pace. When they built the satellites, they built the atomic clocks in each one to the wrong time base. They actually didn't read correctly on earth.
Once in space, if you were sitting on the sattelite, the time would still be wrong. However, the earth perceives the satellite atomic clock as working fine once it's in motion relative to earth. No, this isn't the doppler effect. It's empirical proof of relativity. It's also one of the coolest things I have read about. I am amazed they didn't make a bigger deal of it.
Yeah, it is getting a bit much. Perhaps someone should bomb some of your buildings, you arrogant jerk.
Why can't they do the same experiment using a space telescope and a pulsar?
If everything were frozen and no particles changed their state (position, speed, etc), would you perceive time "time" passing?
Can you tell time passing by watching a pine or a birch or some other tree (do you have the patience for that)?
Time is just a way to measure something RELATIVE (change), just like x y and z dimensions compared to an arbitrary reference unit.
There are a lot of GR corrections that one must make to GPS to get decent accuracy out of it. In fact, there is a bit of a scandal because none of the GPS receiver makers have made public their correction formulae (standard "if we publish then we'll just be helping our competitors" philosophy).
There was a good article in the May edition of Physics Today about relativistic corrections to GPS, unfortunately the web version isn't free. If you're near a university, they should have copies of PT in their physics library.
Actually, GPS knows about this and takes advantage of it. It is the only consumer relativity application I know of.
The GPS SV's are going about 3900 m/s which is a sufficient percentage of the speed of light for relativity to come into play. If relativity weren't taken into account and Einstein obeyed, you'd be off by ~100 meters.
The correction could be done in the receiver or the signal could be biased in the SV. Following the Principle of Alice's Restaurant:
Factoring this correction into the SV, the onboard clocks use a frequency of 10.22999999543 MHz and your GPS receiver uses 10.23 MHz. This simplifies the GPS receiver software immensely.
GPS was designed during the 1970's by some really smart forward thinking guys.
The CNN article is one of the worst examples of science writing I've *ever* seen. I even thought of submitting it for that purpose alone. Now, what does it mean that Slashdot took it seriously? Good lord.
Why do I keep seeing all these instructions for building stringed musical instruments? "Do thing A, do thing B and viola!"
;)
Or perhaps you mean "voila!"
Look it up, do a google search or something. Do your own homework, before posting something you obviously know little about.
-- Waht? Tehr's a preveiw buottn?
It doesn't really matter until you meet the other person again anyway.
... but once you're both in the same reference frame again things will have settled out so that you agree on the "direction" of the discrepancy.
The acceleration along the path you each take determines who, if anyone, is ahead.
If your trips were mirror images of each other, then on the outgoing journey (accelerating away) you'd each see the other's clock slow down.
On the way back (accelerating towards one another), you'd each see the other's clocks speed up again until they were back in synch when you met.
If the trips were not completely symmetric, then there will be a discrepancy
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DNA just wants to be free...
How is this off-topic?? One of the guys who works on the experiment in question, Chuck Lane, just said here (in comment #3644864) that this experiment is intended to test for things like string theory!
Einstein's skeleton v. Hawking w/o wheelchair? Now that's tasteless entertainment.
It's a common misconception that Einstein's theories prohibit FTL travel - they do not.
Technically, no they don't. Practically, they might, because the transformation of time/space coordinates screws up causality. For example, we send a spaceship from Earth to Neptune faster than light. It leaves Earth at 1:00pm and arrives at Neptune at 1:06pm (Central Daylight Time, before you complain about time zones - we're launching from my backyard). In the frame of reference of an alien spacecraft moving past Earth at a high sublight speed, 1:06pm at Neptune occurs earlier than 1:00pm at Earth. This is because of the transformation of space-time coordinates. If the aliens have to wait for light from Neptune to get to them to see it, we're OK, but if they have some kind of subspace sensors that can see the event as it happens (in their reference frame), they can prevent the launch after they've seen the arrival at Neptune. Oops.
A good space-time diagram is worth a thousand words, so look here for more. The example he uses is different, but the idea is the same.
His site also has an explanation of how FTL might work without these paradoxes. It hypothesizes a special reference frame (subspace, of course) for objects traveling faster than light. This reference frame would match that of nearby massive objects (planets, stars, etc). In this model, the information that our ship had arrived at Neptune could not go backward in time relative to our solar system, so the aliens could not know the ship arrived at Neptune in time to stop it.
Incidentally, this means that a ship moving at sublight speed through a solar system would be able to use its subspace sensors to see things that have just happened in our reference frame, but are actually in the future in theirs. But, they can't do anything with the information to prevent the event before it happens.
Unfortunately, we have no way to verify any of this sort of speculation, and probably won't for the foreseeable future. It's clear that if relativity as we understand it is correct, then FTL travel can violate causality. Whether this means it's impossible, no one knows.
Hey kids, there's only 5 days left 'til Yak Shaving Day!
In fact the opposite is the case. No one has any reason to believe that general relativity is in error, but as part of good science it is being tested anyway. One can never prove a theory; one can only disprove it. So the best you can do is test your theories with greater and greater precision as the opportunities present themselves.
It's a case where this is, in effect, a pretty mundane story (a very well-established theory is being routinely tested), but the journalist in question is implying that there is some doubt as to its validity. Of course, it's possible the experiment will reveal deviations from general relativity's predictions, which would indeed involve "minor corrections" to the theory since it is so accurate in other areas, but there is a definite spin being put on the story which isn't in the underlying facts.
If science proves that the passage of time is relative, then the Christians can use science to prove the biblical account of creation! (that is, from one perspective the creation of earth took six days, but from another perspective it took millions of years) They already have the order of creation going for them (stars & planets first, then pangea, then the skies clearing and the sun & moon & stars being visible from earth, then plants, sea life, land life, and finally, humans). We must stop this now! We can't let science prove god any more!
That darn ether is everywhere I tell you! It's messing with their heads!!
You have a huge rocketship that just happens to be capable of going 2/3 the speed of light. Inside this rocketship you have a smaller version of the rocketship that can also do 2/3 the speed of light. The first rocket speeds up to 2/3 the speed of light, then the smaller rocket accelerates to 2/3 the speed of light and exits the large rocket. This smaller rocket is now doing 1 1/3 the speed of light, is it not? But that's not possible. I have no physics capable friends so I figured I'd ask on slashnerd when an appropriate article came up.
One of the stupidest things I ever heard about physics was that it refused to deal with the subjective perceptual experience (for example, the "green" you experience looking at a tree.)
These are a very real, existing, physical phenomenon. That it is "introspective" is a cop-out of physics.
AI has made little progress in that, either. Until better computers come along, they still can't get past the question of whether such perceptual experience arises as a physical phenomenon of the brain, or as a physical phenomenon of the data pushing the brain itself does. Note to the religious: pushing it into the spirit world only suggests an acompanying spiritual physics, sorry to say.
"Has [being a kidnapped teenage girl, raped repeatedly for months] changed you?" - Katie Couric to Elizabeth Smart
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Kevin: So, you're doing a little painting.
Dave: That's right Einstein. How'd ya guess? I mean, I was trying so hard to hide it. Huh Einstein?
Kevin: Listen, not everything that comes out of my mouth is the theory of relativity. So can the sarcasm.
Dave: Sorry, did I hurt your genius feelings?
Kevin: Walk away, walk away... you're the genius, he's a painter... you're clearly the winner here. You figure things out, he paints things up.
To a reductionist, everything in the universe is in principle a physics problem, right down to politics and sociology. In practice, however, those subjects fall outside the scope of physics.
Not even if I open the doors and stick out my head? ;-)
This thing all things devours;
Birds, beasts, trees, flowers;
Knaws iron, bites steel;
Grinds hard stones to meal;
Slays kings, ruins town,
And beats high mountains down.
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.