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


Forgot your password?
The Internet Science

New Distributed Project Seeks Gravity Waves 234

fenimor writes "Much like the popular SETI@Home distributed computing project that searches radio telescope data for signs of extraterrestrial life, the new Einstein@Home will search for gravitational waves in data collected by U.S. and European gravitational wave detectors. Albert Einstein's General Theory of Relativity predicted the existence of gravitational waves in 1916, but only now has technology reached the point that scientists hope to detect them directly."
This discussion has been archived. No new comments can be posted.

New Distributed Project Seeks Gravity Waves

Comments Filter:
  • by Anonymous Coward on Saturday February 19, 2005 @05:20PM (#11724424)
    What do gravity waves tell us that EM radiation doesn't? Will these measurements allow us to image distant objects that are otherwise invisible?
    • by turnstyle ( 588788 ) on Saturday February 19, 2005 @05:26PM (#11724451) Homepage
      "What do gravity waves tell us that EM radiation doesn't?"

      It would be another confirmation of Einstein's theory. Some more background here [].

      And here's some about a recent satellite [] also hoping to establish the existence of gravity waves.

      • by LionMan ( 18384 ) <leo.stein@gm a i> on Saturday February 19, 2005 @06:12PM (#11724715) Homepage Journal
        Sorry, gravity probe B (the recent satellite) is not trying to confirm the existence of gravity waves. GPB is looking for "frame dragging," another predicted effect of general relativity. Gyroscopes in GPB should precess, despite the fact that they are over the poles of the earth and (to first order, excluding motion about the sun and the motion of our solar system itself) not in a rotating frame. Even though the gyroscopes won't be in a rotating frame, their spacetime metric will be 'dragged' by the rotating massive earth, causing a precession of some parts of arcseconds (check the web page for more).
      • Something about using Wikipedia as a definitive reference for anything leaves me underwhelmed.

        And, yes, go ahead and mark me Troll

        • I wouldn't consider it definitive. I would consider it a starting point. It is easy to look something up there and if it is interesting, you can then dig further at least knowing what some of the concepts are about. My 10 year old son uses Encarta the same way.

      • The Wikipedia article is quite good. It even explains the difference between gravity waves and gravitational waves.

        However, I would like to point out that any theory of gravitation that requires the effect of gravity to move at a finite speed will predict gravitational waves. Only the details of the wave will provide a confirmation of Einstien's theory.
    • by cot ( 87677 ) on Saturday February 19, 2005 @05:31PM (#11724473)
      If you detect gravity waves from sources like supernovae, black hole collisions, etc. you're confirming that Einstein's GR works and that the properties of the waves (ie amplitude, duration) make sense for that particular source.

      If you can detect primordial gravity waves from the very early universe(harder!), you now have an indication that inflation (rapid expansion) of the universe is a reasonable cosmological model rather than its current somewhat ad hoc status. It nicely explains away some problems with simpler models, but no real direct test has been performed to show that it happened.
    • by StupendousMan ( 69768 ) on Saturday February 19, 2005 @05:40PM (#11724529) Homepage

      First, the direct detection of gravitational waves would confirm certain aspects of the theory of general relativity, as other posters have noted.

      Second, gravitational wave detectors will provide us with a new window to the universe. Ordinary stars emit mostly visible light, so ordinary optical telescopes are well suited to their study. Cold clouds of interstellar gas emit mostly radio waves, so radio telescopes are the best choice to study them. We know of certain objects --- relatively uncommon ones -- which ought to produce a good deal of gravitational radiation: very massive objects moving very quickly, such as pairs of black holes or neutron stars orbiting around each other at small distances. Gravitational wave detectors will allow astronomers to study the properties of these objects more precisely than we can with ordinary telescopes (since they do not emit much electromagnetic radiation).

      Finally, it is possible (though I suspect unlikely) that the universe may contain a whole class (or classes) of objects which are currently unknown to us, but which will appear as strong sources of gravitational radiation. Almost every time astronomers have added a new type of telescope to their toolkit, they have stumbled across previously unknown phenomena. The first gamma-ray telescopes, for example, revealed gamma-ray bursts, which were completely undetected (and unexpected) by other means in the late sixties and early seventies.

      One last note: LIGO and other gravitational wave detectors provide very poor angular resolution, compared to ordinary optical telescopes. They will tell us something like "a source of gravitational waves is over there, about 10 degrees above the horizon at 5 degrees south of East." The "error circle" for a typical detection will be a few degrees in size. It may be quite a challenge for astronomers to identify the optical counterpart to a new source of gravitational waves, since there will usually be thousands to millions of optical sources within the error box of a gravitational wave detection.

      • Actually, the angular resolution is worse than that. The antenna pattern of the LIGO and VIRGO projects is close to 90 degrees of sky. However, work is under way at Caltech to use multiple detectors (like LIGO Hanford and Livingston) in a fashion similar to how radio astronomy uses multiple dishes to form a more sensitive, finer resolution antenna (this is based on interferometery).
        The stochastic gravity wave background, which is a prediction of inflation, is predicted to be at power levels which are curren
      • The first gamma-ray telescopes, for example, revealed gamma-ray bursts, which were completely undetected (and unexpected) by other means in the late sixties and early seventies.

        Mostly true. Gamma ray bursts were first discovered by DoD satellites that monitored the Gamma spectrum in an attempt to ferret out clandestine nuclear tests and/or the usage of nuclear weapons (in combat). The first Gamma-ray telescopes were launched partly in connection with that discovery. (Though the DoD contribution was not

    • You also have to keep in mind that for something about which we know so little, learning more about it will probably lead to applications we haven't even thought of yet. When X-rays were discovered, do you think Roentgen immediately thought of using it for detecting weapons in bags or measuring atomic spacing in crystal latices? Probably not. It could very well be useless, but I expect we will find something useful to do with them if and when we detect them (assuming they exist).
    • Gravitational Radiation being much weaker, thus harder to detect, does not interact with matter like the electromagnetic radiation does. As a result, gravitational waves produced by spiraling binary star systems, coalescing stars, supermassive black holes etc will be unaltered when detected giving us a completely new perspective in how we look to the universe. It will be like the transition from optical telescopes to x-ray ones.

      An excellent, popular book about the topic is Black Holes and Time Wraps by Kip
    • There are a couple of main points to note in answer to your question. Firstly, verifiable detection of gravitational waves in spacetime would provide us with yet another confirmation of general relativity. This is important not only in demonstrating that general relativity is an accurate model of large scale phenomena in the universe, but also provides us with more evidence that any theory of quantum gravity must reproduce all of the predictions of general relativity at the appropriate energy levels. This i
    • To add to the postings above:

      One of the most load sources of gravitational waves are collapses of binary neutron stars or black holes.

      If a waveform of such a collapse is found it should first obey Einstein's equations and then quickly transition into the regime of quantum gravity which we know nothing about.

      Such information would be extremely valuable as (at the moment) there is no way we can experiment with quantum gravity in a laboratory - the energies involved are far beyound what current accelerators

  • Bah humbug. (Score:4, Interesting)

    by dauthur ( 828910 ) <> on Saturday February 19, 2005 @05:24PM (#11724436)
    Even though it's one of the most popular philisophical astronomy books ever, A Brief History Of Time (Stephen Hawking) really happened to open up my eyes, and I sought extra reading. After all this time, even beforeward, I knew about gravitational waves considering the 4th dimension. The thought of actual waves though seems hard to imagine, considering gravity comes from mass, not anything non-particle. The idea that a massive supernova could propel gravitational waves at us in such a way as it does micro gamma and cosmic waves sounds absolutely rediculous unless, of course, the actual mass encounters us too (That would take a while).
    • Is it difficult to believe that we see distant objects? The light waves reach us after travelling through spacetime; we don't have to be touching a distant star to see it. Similarly, we feel the pull of gravity of every other object in the universe (and not only massive objects, such as matter. It is the curvature or energy density of spacetime which couples to the gravitational force. Weakly Interacting Massive Particles should contribute to the pull of gravity we feel, as should the energy density of a va
    • Electric charges and their motion are the sources of electric and magnetic fields. However, you can also have electromagnetic waves (radio waves, light, gamma rays, etc.), which are self-purpetuating in the absense of charges. These wave are produced when an electric charge accelerates and keep going far away from the charge that produced them.

      Mass and energy* are the sources of gravitational fields, and, in fact, Newton's law (which is an approximate description of gravity in certain situations) looks

  • Relevant link (Score:5, Informative)

    by Anonymous Coward on Saturday February 19, 2005 @05:26PM (#11724450) []

    Posting as AC to avoid karma whoring.
    • I don't understand why it would be karma whoring to supply a relevant link. Others post blithering nonsense and outrageously stupid opinions and regularly get modded Insightful. Do you really feel so guilty about contributing useful information that you post it anonymously?

      Next time just post the link, a short description of what it is about, and glory in being able to provide useful info.
      • It's a holdover. People used to post relevant but obvious information in an attempt to get their karma number as high as possible.

        Stuff like how Einstein@ home is running on BOINC, which also runs SETI@home
        so it should be pretty stable. Anyone who read the articles or attempted to sign up would know that, but most of the mods didn't do either.

        They were playing the Karma game, back when karma was permanently accrued and displayed. People got their Karma numbers up into the tens
  • Can this project lead to an anti-gravity engine? Obviously, the first engine will not be powerful enough for a spaceship to escape the gravity of earth, but maybe it will lead to maglev cars that don't require special tracks like the train.
    • Dude! Star Trek! Not real!! Data!
    • WHAT? RTFA, because you're way off track.

    • by Anonymous Coward
      No. There is no antigravity in Einstein's gravity. And even if there were with negative mass or exotic matter to produce local antigravity effects, detecting gravitational waves still would not help acheive that goal.
  • Not to push this down, but isn't Folding@Home [] a little more important for humanity overall?
  • by SushiFugu ( 593444 ) on Saturday February 19, 2005 @05:45PM (#11724557)
    The $randomwisdom at the bottom of slashdot currently reads "When things go well, expect something to explode, erode, collapse or just disappear." I sort of deep down hope they don't find them now.
  • I read in some books, that gravitational waves were observed in the 70s years in one of the first built detectors. The source of the waves was the centre of our galaxy.
    Unfortunately the experiment was not confirmed in a latter one, and it is believed, that something else was observed in this moment.
    Did someone knows something else about this first experiment?
  • LIGO project (Score:4, Informative)

    by karvind ( 833059 ) <> on Saturday February 19, 2005 @06:00PM (#11724640) Journal
    Laser Interferometer Gravitational Wave Observatory [] from Caltech is working on same subject. LIGO will search for gravitational waves created in supernova collapses of stellar cores (which form neutron stars and black holes), collisions and coalescences of neutron stars or black holes, rotations of neutron stars with deformed crusts and the remnants of gravitational radiation created by the birth of the universe. LIGO is a joint project between scientists at the California Institute of Technology (Caltech) and the Massachusetts Institute of Technology (MIT), sponsored by the National Science Foundation (NSF).
  • by ArcCoyote ( 634356 ) on Saturday February 19, 2005 @06:06PM (#11724677)
    The kickass OpenGL screensaver it gives you!

    The BOINC [] versions of Seti@Home and Climateprediction are similar.
    You can attach to all of them and have the client devide your CPU time any way you want.
    BOINC also has a folding client (predictor@home), but there's no eye candy.
  • by thijsa ( 849477 )
    Why are so many people participating in seti@home when both the goal and the expected result are kind of weak? It seems that an ideologic goal seems to attractive power of an ideologic goal is higher than the repelling power of a low chance of success. I would rate this as a goal irrelevant to most people and an undefined chance of success, so why join? In my opinion, biology projects with protein folding to find cancer/AIDS cures seem to have the best chance of success/utility product.
    • Why are so many people participating in seti@home ... I would rate this as a goal irrelevant to most people

      Apparantly all those people participating in seti@home don't lend much credence to your ratings, but have made their own choices of where to spend their resources, on goals they do find relevant.

  • And that's where you'll fiind what SETI is looking for. Radio is a thing of the distant past for civilizations who have lived long enough to learn how to not kill each other off. Gravity waves are not blocked or obscured by anything, and the only source of emissions at GHz frequencies are alien-made.
  • by John Hasler ( 414242 ) on Saturday February 19, 2005 @06:42PM (#11724927) Homepage
    No thanks. I don't donate to people who claim to own data.

    They also make no mention of license terms or client source availability.
    • The only reason the claim to ownership is there is so that if your machine is the one that analyzes the parcel of data that reveals Gravity Waves, you can't take credit away from the Project by claiming that you discovered it. Also, that would probably make it illegal to alter the data, which would render the @home process illegal. The same goes for client source code, if the programs were modify so that the data was analyzed differently than everyone else's, it would be useless to compare to the others.
      • I understand that explanation. But I don't totally accept it. Certainly, e.g., the cancer@home people have a signigicant financial interest in owning the result, and being able to control who can benefit from the cure. Similarly the folding@home people stand to accrue significant financial benefit.

        I'm really considering donating this time, because I *DON'T* see that there is a large financial benefit to owning the data. If I did, then I'd want significant comitment that they wouldn't restrict the right
        • Couldn't agree more. I've stayed away from folding/cancer for the same reasons.

          My logic is this:

          If you're doing something for the general benefit of mankind with the results being free for all to use/extend, then I'll follow your lead and let you use some spare cycles on my PC (which do cost me money since my PC would otherwise throttle the CPU/fan/etc).

          If on the other hand you plan on selling your results to the highest bidder then this is a commercial enterprise and you had better be prepared to make
      • > The only reason the claim to ownership is there
        > is so that if your machine is the one that
        > analyzes the parcel of data that reveals Gravity
        > Waves, you can't take credit away from the
        > Project by claiming that you discovered it.

        Nonsense. Even if a single parcel was able to "reveal gravity waves" they would be the first to know. The results must be sent back to them for comparison with other results before anything can be "revealed".

        > Also, that would probably make it illegal to
        • And how exactly do you verify that it is coming from signed binaries from the site? They could just compile their own version and have it use the other binary any time it asked it to prove it was the real client. The real way, and this is the way that SETI at el do it, is to assign duplicate data occasionally and randomly and pick out any results that aren't the same.
    • No thanks. I don't donate to people who claim to own data.

      Definitely not, Data has shown time and again that his 'quest' for humanity as much as makes him human. Data wants to be free
    • No thanks. I don't donate to people who claim to own data.

      Glad someone else noticed this bit:

      "Use of LIGO and GEO data - Data supplied for analysis with Einstein@Home are not to be used for any other purpose without the consent of the LIGO Scientific Collaboration (LSC)."

      I love it when projects paid for with public money think they can control how their stuff is used.

  • even bigger breakthrough would be finding a gravatron to verify string theory. Fermilab has the technology and is currently searching another machine is being built and when it is complete it will blow Fermilab's technology out of the water. Ed Whitton is the man!!! combining 5 theories into one (M theory) was a regular saterday night event for him! Yes! -Ro
  • why do we care (Score:2, Interesting)

    by liquidpast ( 859065 )
    I have been lucky enough to be working on a similar project for the past few years. We also use distributed computing but only via our local clusters. We don't actually analyze data from the interferometers, rather we try to figure out what waveforms we would get from a particular set of objects (mostly pulsars). As far as I understand (I'm but a lowly undergrad), the main reasons why we study gravitational waves are
    1. because unlike EM waves which get deflected by just about everything they pass by, grav
    • I mean I'd love to live forever, but I would sacrifice the possibility instantly if I could actually go and see the universe out there before I died.

      I agree. Humans are not the center of the universe, and there are more important matters in the universe than humankind. Therefore I think there are more important distributed projects than Folding@Home. And that's just my humble absolutely true opinion ;)

  • We have a team. (Score:2, Interesting)

    by X0563511 ( 793323 )
    If anyone cares, we have a team Slashdot. id=584 []

    If you run einstein@home, get yer arse on it.
  • Heh..I replied to the dupe thread on the galactic flash before I even realised this thread was up. I swear the association must have been accidental or subconsious :) Anyway, I thought I'd post it here as the other thread is likely to be dupe-flamed into oblivion:

    "Even though it's a dupe, this is the first time I saw this story. Now I know I'm thinking of correlations in the wild, but 10,000 trillion trillion trillion watts is a large amount of energy.

    Two days earlier, there was a massive earthquake. I wo
  • by TMB ( 70166 ) on Saturday February 19, 2005 @07:19PM (#11725103)
    The blurb correctly says that they are looking for gravitational waves. The title incorrectly calls these gravity waves.

    Gravity waves are waves where displacement from equilibrium in a medium is counteracted by the force of gravity. For example, the waves on the surface of a pond are due to regions that are higher getting pulled down by gravity.

    Gravitational waves are a phenomenon in general relativity where accelerating dense masses cause waves in the space-time metric that propogate at the speed of light.

  • project MiniGrail (Score:3, Informative)

    by rjdegraaf ( 712353 ) on Saturday February 19, 2005 @07:28PM (#11725165)
    At Leiden University in The Netherlands a project called MiniGrail [] tries to detect gravitational wave produced by neutron stars.
  • All I can do with firefox is to get it to output the binary data to firefox's screen, so the ability to do a preper download seems to be broken.

    I've not had any problems of a .gz file doing that previously.

    This gravity wave search rather intrigues me, but if I cannot dl the boinc manager, what good is it to do a linux version if the webmaster putting it up for dl hasn't the foggiest what a .gz file really is?

    Cheers, Gene
  • by Anonymous Coward on Saturday February 19, 2005 @08:00PM (#11725352)
    This pisses me off. I saw Kip Thorne lecture on LIGO project. They are spending lots of $, a few billion, on detectors, but they presumptuously PRESUME they will be able to use the free cycles of a distributed project to wade through their "data". (The gravity wave detectors are supremely sensitive motion detectors, and the gravity waves they hope to detect are expected to cause motion fluctuations MANY TIMES SMALLER THAN A SINGLE NEUCLEUS. On top of this "signal" with be noise of all vibrations around, cars on the street, slamming doors. etc. From the data they hope to extract signal by analysing and canceling noise; this is what the distributed project is supposed to do.) What pisses me off is they aren't budgeting for their own computer resources, they are leeching off the donation-net. Which takes away from other projects that really have no budget , and/or really are more important, and/or more likely to have a positive outcome. Example: SETI at home is low budget, they are piggybacking data acquisition from device built for other purpose (Aricebo), so the donations make sense; they allow something to happen that otherwise not. Folding@home, actually could help health. Mersenne primes, brute-forcing ciphers, a nice hobby, kinda boring and pointless to me, but no budget; each to his/her own. BUT LIGO is BIG SCIENCE, ($billions) yet they don't budget their own computational needs. In a way it's fraudulent to set up experiment on that basis; without the computations, you don't have an experiment, yet you ASSUME people will give you computer time, BUT that computer time is being drawn from a finite pool of well-wishing volunteers, and thus causing a loss to those other projects who really have to budget.

    Thanks for giving me this opportunity to vent.

    Slashdot, please make your text entry box a little wider.

  • Wow, that would be my professor Bruce Allen. I'm taking Physics 210 at UWM this semester and he's the one who lectures to me every Tuesday and Thursday. Good professor who studied under Stephen Hawking.
  • by steve_bryan ( 2671 ) on Saturday February 19, 2005 @10:05PM (#11726070)
    They should have written an actual Mac OS X application before advertising their project to the public. Even within the constraints of users who don't mind using the Terminal for manipulating and launching processes it is inadequate. In the terminal the first thing it did after using chmod +x to make it executable was come back and request the URL for the project. Say what? There is nothing in the documentation that I could find indicating something like this would be asked. Then after proceeding a bit further it indicated it could not find the choices I had made to the parameters it uses to govern how it will run so it set them to defaults!

    I'm supposed to trust these amateurs with my Mac? If they don't have the needed programming knowledge they need to get it and do so before inflicting unnecessary havoc on unsuspecting voluteers. Take a look at Folding@Home or SETI to get an idea of what you need to have done before you ask the public to trust your work.

"You stay here, Audrey -- this is between me and the vegetable!" -- Seymour, from _Little Shop Of Horrors_