Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
NASA Space Science

Is the Earth in a Vortex of Space-Time? 249

Posted by Zonk from the pinwheel-pinwheel-spin-me-around dept.
da6d writes "Apparently, we'll soon know for sure.... NASA has announced in an article that 'A NASA/Stanford physics experiment called Gravity Probe B (GP-B) recently finished a year of gathering science data in Earth orbit. The results, which will take another year to analyze, should reveal the shape of space-time around Earth--and, possibly, the vortex.'" More from the article: "If Earth were stationary, that would be the end of the story. But Earth is not stationary. Our planet spins, and the spin should twist the dimple, slightly, pulling it around into a 4-dimensional swirl. This is what GP-B went to space to check."
This discussion has been archived. No new comments can be posted.

Is the Earth in a Vortex of Space-Time? More

Is the Earth in a Vortex of Space-Time?

Comments Filter:

  • Space (Score:5, Funny)

    by nycheetah ( 172069 ) on Saturday November 19, 2005 @03:11AM (#14069381)
    Live long and vortexed?

  • A time, cube perhaps? (Score:4, Funny)

    by invisigoth ( 131518 ) on Saturday November 19, 2005 @03:11AM (#14069382)
    Is Dr. Gene Ray behind this discovery?

    http://www.timecube.com/ [timecube.com]

  • uhh (Score:5, Funny)

    by flamesrock ( 802165 ) on Saturday November 19, 2005 @03:12AM (#14069384)
    "If Earth were stationary, that would be the end of the story. But Earth is not stationary."

    Are you on crack!? The earth is stationary. It is the sun that's moving.

    • Re:uhh (Score:5, Funny)

      by Belseth ( 835595 ) on Saturday November 19, 2005 @03:49AM (#14069482)
      "If Earth were stationary, that would be the end of the story. But Earth is not stationary."

      Are you on crack!? The earth is stationary. It is the sun that's moving.

      It's the fact that it's flat that gives it the illusion of motion.

      • Re:uhh (Score:2, Funny)

        by Ninjy ( 828167 )
        It's the fact that it's flat that gives it the illusion of motion.

        The crack probably helps.

      • Re:uhh (Score:5, Funny)

        by MarkRose ( 820682 ) on Saturday November 19, 2005 @05:26AM (#14069670) Homepage
        It's the fact that it's flat that gives it the illusion of motion.

        No, it's flat because it's stationery, duh!

        • Re:uhh (Score:3, Funny)

          by metlin ( 258108 )
          No, it's flat because it's stationery, duh!

          Who says stationery have to be flat!?

          My new Sharpie has some sweet curves.

          And don't even get me started on my red stapler...

        • Re:uhh (Score:5, Funny)

          by ObsessiveMathsFreak ( 773371 ) <obsessivemathsfreak.eircom@net> on Saturday November 19, 2005 @09:52AM (#14070199) Homepage Journal
          No, it's flat because it's stationery, duh!

          No. The Earth is too complex to have just ended up flat with the sun spinning around it. A higher power must have had a guiding hand. So we should instruct kids on the Intelligent Flat Earth Design Theory over the Newtonian-Einstienian theories of gravity, which are after all, completely unprovable.

        • all this racket you, guys, are making is completely distructing me from my research of the epicycles.
        • It's flat because some one let the air out. Ever try to roll a flat tire? If people would just use common sense science would make sense.

    • Comment removed (Score:5, Interesting)

      by account_deleted ( 4530225 ) on Saturday November 19, 2005 @04:56AM (#14069608)
      Comment removed based on user account deletion

      • Re:uhh (Score:5, Insightful)

        by LionMan ( 18384 ) <leo...stein@@@gmail...com> on Saturday November 19, 2005 @07:00AM (#14069848) Homepage Journal
        What is meant is the following:
        One of the exact solutions to the Einstein field equations is a decent assumption for the Earth's (or anything approximately spherical which is not moving relativistically) gravitational field. The curvature of space-time is greater the closer to the center of the massive body. A light ray travelling some distance from the massive body will be deflected from a "straight line" (which is hard to define in curved space).
        If you are taking the view that you start rotating the rest of the universe around us, then it is equivalent to having your coordinate system spin around the massive body (well, there is nothing besides the massive body in the universe I am imagining). Physically, light will follow the same path as it did before, since all you have done is redefine the coordinate system, which does not change physics!
        Now instead, consider spinning the Earth, instead of the coordinate system. The matter making up the earth now has more energy-momentum (the magnitude of which is a physical quantity which can be measured independent of reference frame, if your frame is freely-falling). Energy-momentum is what causes space-time to curve, so a light ray travelling the same distance from the earth will be deflected by a larger amount, since space will be more curved.

        • Re:uhh (Score:2, Interesting)

          by Impy the Impiuos Imp ( 442658 )
          Then again, I thought the other test results a few years ago demonstrating gravity was bound by the speed of light suggested its particulate exchange nature, and thus it was not a fundamental feature of spacetime geometry.
      • What the hell does "stationary" mean in space?

        It means that you can use it to write a nice letter to a friend.
      • Speaking of observers, here's an interesting tidbit. Last year, there was a guest lecture at Delft uni by one of the ?project managers? of the project (nice guy, american, worked with NASA and the american research uni who did a lot of the work on this probe).
        It was a very interesting lecture, but at the end of it, during the Q&A part, one of the professors asked what amounted basically to this: "well, it's good and well that NASA created this purpose built satelite, but wasn't there recently an existin
      • One reasonable definition would be "stationary with respect to the frame of reference of the bulk of matter around it." This does, of course, beg several questions about whether your frame of reference is the solar system, at which point we're doing a loop, or the galaxy, at which point we're doing some funky spirograph thing, or in fact the universe as a whole, wherein legitimate arguments can be had about what exactly we're doing.

        That said, even if you're trapped in the 1500s and want to pretend that the

    • Re:uhh (Score:2, Funny)

      by Circlotron ( 764156 )
      That's right. Ask any astronomer what time the sun rises and set today and he won't for a moment think you are being silly.

  • So... (Score:2, Funny)

    by joetheappleguy ( 865543 )
    If the Earth is in one of those time vortex things do I get paid overtime?

  • well at least (Score:3, Funny)

    by Compaq_Hater ( 911468 ) on Saturday November 19, 2005 @03:15AM (#14069400)
    that explains the Bermuda Triangel huh ?, Maybe we will find flight 19 and a bunch of missing Millitary too.

    CH

    • Re:well at least (Score:4, Funny)

      by guttentag ( 313541 ) on Saturday November 19, 2005 @05:36AM (#14069691) Journal
      that explains the Bermuda Triangel

      No, "Our planet spins, and the spin should twist the dimple, slightly" explains leap years, daylight savings time, and the previously inexplicable 1.42-minute-per-month gain on my employer's time clock.

      "A three-sided vortex (once limited to the greater Bermuda area but in recent years expanded to be anchored at Crawford, TX, Washington, DC, and Baghdad due to depletion of the ozone layer) into which pour vast sums of the rest of the world's time and money" explains the Bermuda Triangle.

      • Re:well at least (Score:2, Interesting)

        by goldseries ( 932320 )
        No, "Our planet spins, and the spin should twist the dimple, slightly" explains leap years, daylight savings time, Leap year exists because the earth takes 365.2422 days to orbit around the sun. This is number is ridiculously too complicated to use so a system was created in which a day is added every four years to make up for the lost .2422 days. In the Gregorian calendar, which is the calendar used by most modern countries (the USA), the following rules decides which years are leap years: 1. Every
    • Related topic... According to this article [cnn.com], they were honored after 60 years.

  • It's all relative (Score:4, Funny)

    by The Nine ( 320384 ) on Saturday November 19, 2005 @03:16AM (#14069402)
    If Earth were stationary, that would be the end of the story. But Earth is not stationary.

    I see they found that universal frame of reference they were looking for.

    • Re:It's all relative (Score:5, Informative)

      by Starker_Kull ( 896770 ) on Saturday November 19, 2005 @03:33AM (#14069438)
      Actually, it doesn't have to do with universal reference frames in the sense you mean. In Newtonian mechanics, there is a limited set of preferred reference frames within which Newtonian physics is valid - the inertial reference frames, or, casually speaking, the ones moving at a constant velocity - none of which is a "Universal" or better reference frame than any other. But even in Einstein's model, which incorporates accelerated reference frames in the same framework as inertial, there are still "preferred" reference frames; non-rotating ones. ROTATING reference frames lead to unambigious differences, both in Newtonian and Einsteinian models. While sloppily written, the article means that it is the ROTATION of the Earth's reference frame that leads to different predicted results, not the TRANSLATIONAL motion. Not all reference frames are created equal.

    • Re:It's all relative (Score:5, Interesting)

      by meringuoid ( 568297 ) on Saturday November 19, 2005 @06:41AM (#14069796)
      I see they found that universal frame of reference they were looking for.

      Doesn't really apply to rotation.

      If you're sealed inside a spaceship moving at constant velocity and cannot refer to the outside in any experiment, you have no way to determine what its velocity might be. There's no physical difference between 'stationary' and '0.999c', until you interact with something outside. Even then, you can still declare that you're stationary and that it is moving and the physics works out the same.

      If, however, you're sealed inside a spaceship rotating with constant angular velocity, that's quite another matter. You'll know about the rotation, either by reference to gyroscopes if it's spinning very slowly, or by the fact that you seem to be stuck to the wall if it's spinning very quickly...

  • So, it looks like someone finally flushed the glactic toilet on this backwater planet based on the artists rendition.

    On the bright side if we did get flushed through the vortex at least we would no longer be located in the unfashionable western edge of the galaxy.

    • So, it looks like someone finally flushed the glactic toilet on this backwater planet based on the artists rendition.

      Who cares as long as the galactic water is spinning the right direction. If it's not we'll have to do something about that to make sure the Galaxy flushes correctly.

      (Yes, I know it's a myth so don't go posting Wikipedia links or others telling me).

  • Whoa! (Score:4, Funny)

    by memeplex ( 910698 ) on Saturday November 19, 2005 @03:21AM (#14069416)
    My Cortex is in Gore-Tex contemplating the Vortex. I'm getting a complex! I need a cold compress! I need to undress. I'm relatively impressed. Er... where's Eminem when you need him? Am I off-topic here?
  • I read it Nasa/ Astrophysics

  • Purple Nurple Probe (Score:5, Funny)

    by Helpadingoatemybaby ( 629248 ) on Saturday November 19, 2005 @03:35AM (#14069445)
    So if I'm to understand this correctly, the spin of the Earth twists the nipples of spacetime?

  • I hope this gets proven because then Tempest will go down in history not as a video game but rather an interactive documentary on gravity.

  • Just In Case (Score:4, Funny)

    by bahwi ( 43111 ) on Saturday November 19, 2005 @03:35AM (#14069447)
    Well, if there's something wrong, it's best to not be caught without your Visual Guide to Surviving Timeless Space [sluggy.com].

    • Funny link (Score:3, Interesting)

      by n54 ( 807502 )
      Parent's link is nice and making fun of the average impression people hold on "no time" (at least that's why I get a laugh out of it) as it doesn't make sense to think of "no time" as hitting pause on your remote control. It seems much more likely (almost a logical certainty?) that "no time" is like hitting a button on your remote control and suddenly you see the whole dvd/whatever in an instant, and in the next instant (not that it would be easy to differentiate between it) you see the whole dvd/whatever a

  • The engineering story (Score:5, Informative)

    by dracken ( 453199 ) on Saturday November 19, 2005 @03:40AM (#14069462) Homepage
    Behind the Gravity Probe B is here [stanford.edu] and here [edn.com]. It is a fascinating read, esp. about the gyroscopes.

    "The four gyro rotors are made of fused quartz, fabricated to an extreme level of material homogeneity and then ground to the near-absolute sphericity (Figure 1). The spheres are round to within 40 atomic layers, which is proportionally equivalent to an Earth-sized sphere with surface height variations of only 16 feet...."

    "It's one thing to have a virtually perfect gyro rotor, but that alone does not provide the necessary performance for this experiment......The electric fields center the rotors to a few millionths of an inch. They did not perform the spinning up electrically, however. Instead, they directed a precise stream of helium gas, traveling at nearly Mach 1, at the rotors. It takes about half an hour for the rotor to reach full speed, and it loses less than 1% of this speed over 1000 years in the super-vacuum of the cavity."

  • Neat (Score:5, Interesting)

    by Starker_Kull ( 896770 ) on Saturday November 19, 2005 @03:52AM (#14069488)
    I think it's interesting - general relativity makes some very hard to verify but specific predictions. Many competing theories to it over the last 50 years have made predicitions that have, one by one, turned out to be false. Rotational frame dragging is (I think?) one of the last unverified ones. According to Newtonian gravitation & mechanics, the rotation or non-rotation of the earth should not affect an orbiting satellite a whit (ignoring "complications" like variable atmospheric drag based on rotation rate, different shape of earth at different rotation rates, etc.), or put more abstractly, the rotation of an axially symmetric mass distribution should not have anything to do with its gravitational field. General relatitivity does not agree with Newtonian mechanics here, which brings up yet another interesting question:

    Is there a difference between rotating reference frames and non-rotating reference frames because of the universe of matter around them, or is it self-generated? In other words, if we "removed" the entire universe except the rotating Earth, would rotation still have meaning? Could we still do an experiment and detect its rotation, or is that an artifact of the universe of matter around it that would vanish when it did? As far as I understand general relativity (and IANAP), it does not make a hypothesis one way or the other. Is the question meta-physical? Or is there some clever way to set up an experiment to actually tell?

    Sigh - sometimes, I wish I was a physicist!
    • Rotational frame dragging is (I think?) one of the last unverified ones.

      I believe this phenomenon was observed much earlier by the Rossi X-ray Timing Explorer (RXTE). I think the author was Todd Strohmeyer (sp?), but I can be wrong in detail.
    • Is there a difference between rotating reference frames and non-rotating reference frames because of the universe of matter around them, or is it self-generated? In other words, if we "removed" the entire universe except the rotating Earth, would rotation still have meaning? Could we still do an experiment and detect its rotation, or is that an artifact of the universe of matter around it that would vanish when it did?

      It would still be simple. Try launching one rocket west, one rocket east. You'll pretty so

    • Re:Neat (Score:3, Interesting)

      by radtea ( 464814 )
      I think it's interesting - general relativity makes some very hard to verify but specific predictions. Many competing theories to it over the last 50 years have made predicitions that have, one by one, turned out to be false.

      This experiment may help kill off one of the more interesting alternatives, John Moffat's asymmetric variant of GR. Moffat is a self-taught savant, now at the University of Waterloo's Perimeter Institute, iirc. He realized that Einstein's equations contained a symmetry condition that
    • I suspect that the impact of rotational frame dragging to be equivalent to the impact on the atmosphere because of the flushing of my toilet. Sure, it will verify theories, but the effect is very tiny.

    • Re:Neat (Score:3, Interesting)

      by kavau ( 554682 )
      The earth's rotation has many direct effects, such as the coriolis force generating turbulence in the earth's atmosphere. You can also take a pole that's thousands of miles long and stick it up into the sky. If the pole is long enough, the centrifugal (pseudo-)force on the upper end will be strong enough to break the pole in half and the upper end will drift away into space.

      None of these two effects depends in any way on the surrounding matter, so I have a hard time imagining they'd go away if you remove

    • ... the rotation of an axially symmetric mass distribution should not have anything to do with its gravitational field. General relatitivity does not agree with Newtonian mechanics here, ...

      However, Newtonian gravity plus special relativity does predict a gravitational analogue of magnetism. The parts of the rotating bodies moving at higher relative velocity experience more relative length contraction, thus appearing to be denser masses.

  • Of course, space-time vortices only appear in the plural zones, and beings from these zones should be wary of travelling in Hyperspace, as the plurality of such beings' nature may cause them to undergo a total existance failure when re-entering normal space.

    Douglas Adams certainly was a hoopy frood.

  • Pretty much everything spinning with mass is in a vortex of space-time, if relativity is correct. The point is, has the Internet run out of good stories for this to be posted on Slashdot?
  • "If Earth were stationary, that would be the end of the story. But Earth is not stationary.

    Atheistic [fixedearth.com] trash [geocentricity.com].
    • Thank you, good troll, for stereotyping all Christians as braindead idiots. I was beginning to worry that no one would bring up that particular one today!
      • Thank you, good troll, for stereotyping all Christians as braindead idiots.

        Actually, I was parodying the usual anti-science idiots I often see crawling around discussions of evolution. They are the ones who associate anything that disagrees with their literal Biblical interpretations as anti-Christian, not me.

  • Rudof Steiner said it 100 years ago (Score:4, Insightful)

    by Qbertino ( 265505 ) <moiraNO@SPAMmodparlor.com> on Saturday November 19, 2005 @08:09AM (#14069983)
    Curiously enough Rudolf Steiner [wikipedia.org] once stated that the laws of physics aren't the same everywhere. According to him they gradually change the further you get away from a certain point in space. He said something like:"Very much like the gravity influence of an object declines the further away you get from it, so do the laws of physics change."
    This could be the proof of his statement.
    • No it won't. GR is derived from several axioms - in particular, the assumption that the laws of physics are the same everywhere that they are meaningful. If G Probe B get expected results, then it would back up this assumption, and do disprove Steiner.
      • in particular, the assumption that the laws of physics are the same everywhere that they are meaningful.

        True, but I think you can even broaden this statement by saying that is just one of the simplyfing assumptions (unless there is a reason to believe otherwise) for any scientific work.

        Anyway, having an idiotic Steiner reference modded up more than your post is a very sad day for /.!

        Have the eco-nuts and new-age-zealots finally overran this place!?
    • Who is Rudof Steiner and why are his opinions on gravity relevant?
    • While the laws of physics may not change, this vortex may alter things to appear as such near a massive object. We're still trying to understand the special phenomenon that is affecting the Voyager space probes, but I haven't heard anyone mention anything about a possible vortex around the Sun. Also spinning and quite a bit more massive than the Earth, the Sun's vortex could affect the probes less and less the further they get from the Sun, revealing the true behavior of physics in areas of space that do
  • And I thought I felt dizzy this morning because of a hangover.

  • Technology moves on (Score:3, Interesting)

    by jmichaelg ( 148257 ) on Saturday November 19, 2005 @09:09AM (#14070107) Journal
    The Gravity probe has been delayed so long that its probable results are old hat. The experiment was conceived in the 60's when the first lasers were built. Since then, airliners now zip around the globe using gyroscopes that shoot a laser around a triangle. If one of the three mirrors accelerates relative to the other two, i.e., the plane turns, the timeframe for the accelerating mirror shifts slightly which shows up as a slight time shift in the laser's transit time. No moving parts and the laser gyro is more accurate, by far, than the old spinning gyros it replaces.

    Einstein would probably have been surprised at this particular application of relativity.

    • Re:Technology moves on (Score:2, Informative)

      by Anonymous Coward
      Laser ring gyros verify the Sagnac effect in relativity, not the Lense-Thirring frame dragging effect. There have been some crude verifications of the latter so far (by the LAGEOS laser ranging satellites for Earth, and some astrophysical observations of accretion disks for black holes), but Gravity Probe B will be the first direct, precision test of the phenomenon.
  • I'm not sure the Earth is, but /. certainly seems to be most days...a vortex of morons.
  • Bah, don't worry about it, there was a 'vortex' *cough*wormhole*cough* but it was closed a few years ago by John Crichton.
  • Hah! We of the pastafarian faith all snicker as you infidels again try to measure space not knowing that his noodly appendage has changed your observation to a space-time vortex.

    Just as the bones of dinosaurs and the stars in the sky were placed by our noodly master, so is this great work of his doing.

    Avast ye ignorant dogs! Worship ye great master and his wee midget. For he be a harsh mistress, and his noodly wrath shall send ye all down to Davey Jones's Locker!

  • Poor Tax Payers (Score:2, Interesting)

    by bobbuck ( 675253 )
    So...NASA is spending zillions of dollars on this experiment which has two possible results:
    1. The experiment agrees with GR and NASA says that GR is right about frame dragging.
    2. The experiment doesn't agree with GR and NASA says that it messed up and they'll ask the tax payers for a do over.

    This experiment is not legitimate. If they get the result they expect, they'll accept the result. If they don't get the result they expect, they'll just say (rightly) that it was a flawed experiment. We won't get an

  • ...about their forthcoming press release?

    From the article: "First, though, there are a lot of data to analyze. Stay tuned."

    They did! The whole press release was to tell us they haven't analyzed the data yet, and to stay tuned for the next press release...

Slashdot Top Deals

E = MC ** 2 +- 3db

Close