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New Distributed Project Seeks Gravity Waves

Posted by timothy on from the jeff-spicolli-knows-where-they're-at dept.

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."

18 of 234 comments (clear)

  1. What do gravity waves tell us? by Anonymous Coward · · Score: 4, Interesting

    What do gravity waves tell us that EM radiation doesn't? Will these measurements allow us to image distant objects that are otherwise invisible?

    1. Re:What do gravity waves tell us? by StupendousMan · · Score: 5, Interesting

      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.

      --
      Michael Richmond "This is the heart that broke my finger."
      mwrsps@rit.edu http://stupendous.rit.edu
    2. Re:What do gravity waves tell us? by Anonymous Coward · · Score: 1, Interesting

      No. Frame-dragging is more analogous to magnetostatics, while gravitational waves are more analogous to electromagnetodynamics.

  2. No more interest? by Anonymous Coward · · Score: 1, Interesting


    What ever happened to distributed.net?

  3. Bah humbug. by dauthur · · Score: 4, Interesting

    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).

    1. Re:Bah humbug. by secretsquirel · · Score: 0, Interesting

      In theory everything propels gravitational waves at us just like micro, gamma, and cosmic waves. The only thing about a massive supernova explosion is that the amount of mass in a certain area would change just enough for it to be noticeable.

  4. Anti-Gravity Engine? by Space_Soldier · · Score: 2, Interesting

    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.

  5. This. by Anonymous Coward · · Score: 1, Interesting

    There is an almost unknown theory that is an alternative to general relativity and quantum mechanics. The only directly measurable difference (as predictable so far) is that for the little-known theory, gravity waves should be dipole. For general relativity, they are quatrapole.

    1. Re:This. by Anonymous Coward · · Score: 1, Interesting

      Maybe I can explain somewhat how this works. I found most of this in a book by somebody who must have really hated Quantum Mechanics (I really wish I could find that book again. When I went back to the same place in the library, it wasn't there). There is a very unexpected effect of applying a very slightly modified form of special relativity to really small effects.

      The additional assumption is made that light rotates in transit. Using the tenets of special relativity, attempting to solve for the angular momentum has a surprise for those who do not not know quantum mechainics: there is a new fundamental constant that is the angular momentum of light per cycle. This conservation of angular momentum provides for the stabality of the hydrogen atom exactly the same way quantum mechanics does, but with no other assumptions like large equations.

      For the theory to be coherent however, the curved time must be extracted out. This is not as difficult as it seems: if gravity waves behave like electromagnetic waves, than the process that procuces magnetic forces also produces another force. This force simply has not been seen the effects it cause look exactly like time dialation.
      Only unexpected result: gravity waves have a strong dipole.

  6. observed first in 70s experiment? by geo.georgi · · Score: 2, Interesting

    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?

    1. Re:observed first in 70s experiment? by Tim+the+Gecko · · Score: 3, Interesting
      That would be the experiments of Weber described in the sci.astro FAQ

      The "something else" that was observed was most likely to be big ordinary vibrations which the experiments were trying to subtract to leave a small signal.

  7. Tune Your Gravio (Gravity Radio) to 93.1GHz by Wingsy · · Score: 2, Interesting

    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.

    --
    If I didn't have absolutely NOTHING to do, I wouldn't be here.
  8. in search for smaller things by Daveznet · · Score: 2, Interesting

    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

    --
    GL HF!
  9. why do we care by liquidpast · · Score: 2, Interesting
    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, gravitational waves pass through pretty much anything unaffected, and so retain a lot of information about the object(s) that created them
    2. they give us information about some objects we otherwise know very little about
    3. they tell us more about how and why gravity works, and we know REALLY very little about that
    4. lastly, if found, they would be yet another proof of general relativity
    And to all those saying that Folding@Home is a much worthier cause, I would say that improving the life of individual humans is super, but to improve the state of humanity as a whole, we need more research into basic physics rather than basic biochem. 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.
  10. We have a team. by X0563511 · · Score: 2, Interesting

    If anyone cares, we have a team Slashdot.

    http://einstein.phys.uwm.edu/team_display.php?team id=584

    If you run einstein@home, get yer arse on it.

    --
    For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
  11. Gravity waves != Gravitational waves by TMB · · Score: 2, Interesting

    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.

    [TMB]

  12. Re:Cool, but... by HiThere · · Score: 2, Interesting

    Unfortunately, BECAUSE it's more relevant and important, I find myself less willing to be taken advantage of. These people end up in control of resources created in conjunction with public effort, and they end up in total control.

    It wouldn't bother me if what they ended up with was publication priority, but they stand to end up with patents that mean they can deny benefits to the very people who helped them. I find this undesireable.

    OTOH, Einsein@home and Seti@Home don't appear to have the commercial motivation, so I don't mind contributing to them. I don't feel like they're trying to take advantage of me, because it's not obvious that there's any unfair advantage available.

    --

    I think we've pushed this "anyone can grow up to be president" thing too far.
  13. "Grassroots project" my ass by Anonymous Coward · · Score: 3, Interesting

    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.