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Gravity Wave Detector Ready For Business

Posted by timothy on from the very-expensive-ripples dept.

Arthur Embleton writes "The BBC has an article about a Gravity Wave Detector. There are two L shaped set-ups. One in Washington, the other in Louisiana. They've got a Laser pointing at a mirror 4km away, watching for the reflection and if it is distorted then it shows that there has been a gravitational pulse, possibly by two Black Holes colliding. The detectors are apparently so accurate they can measure to one-thousandth of the width of a proton! How did they test that it works?"

8 of 53 comments (clear)

  1. They'll probably find something else by Anonymous Coward · · Score: 1, Interesting

    Start looking that closely at the fabric of the universe and things are likely to start jumping up at you.

    Kind of a serendipity type situation. Hell, maybe there's some sort of unanticipated effect of some sort of technology we have on earth that will be picked up by the thing. Oscillations from the sun. Maybe the earth is ringing sympathetically with the gravity waves that pass through it.

    Too bad they can't rig this thing up with a bunch of elements. Maybe generate images of a sort.

  2. so many things about it by lingqi · · Score: 3, Interesting
    1) here is an excellent presentation about how it works, etc. something about the sensitivity is on the order of measuring saturn moving toward the sun by the distance of the diameter of a proton.

    2)here toward the bottom of the page you can LOG IN to their system and view all the logs. the password and login is blatantly displayed on the site. we should all email the site admin to have this changed.

    3) I hope they figured it out for 300 million dollars, but wouldn't changes in gravity wave stretch / compress the tubes AND CAUSE REDSHIFT / BLUESHIFT in the lasers therefore cancelling out the effect?

    --

    My life in the land of the rising sun.

  3. They got them elsewhere too by lingqi · · Score: 1, Interesting
    virgo in italy, GEO in Hung^H^H^Hannover, and TAMA in Japan. There is talk of building one in Australia, too.

    All of them I approve, but what's up with Japan? Japan gets some 1,200 minor earthquakes per DAY. how in the world do they expect to overcome the seismic noise floor (pun somewhat intended)?

    --

    My life in the land of the rising sun.

  4. Re:Doesn't matter by Mt._Honkey · · Score: 4, Interesting
    Millions of dollars in federal grant money later, do you think anyone gives a rat's ass?
    Don't bother us with details like "how do you verify that it's calibrated?". There's a board of directors who have pensions! Nice little retirement nesteggs!
    I know that this is a troll, but I am going to respond anyway. I know/work with physicists at Fermilab, and I can vouch for how hard these people work to make sure that everything works perfectly and that data generated is valid. They have teams of people checking to make sure that every assumption made is correct (I'm involved in one such group). Physicists like those at Fermilab, or LIGO, or other such facilities are among the most dedicated, competent people you will ever meet. They aren't there for the money, they are there for the science. Even after they "retire", many continue to work for decades for free. Physicists are there to get shit done, and I'm sure that their retirement benefit packages are not their primary motives.

    If that were the case, I doubt that they would have gone through 4 hard years of painful undergraduate courses, followed by even harder grad school, then working through a post-doc position... all to secure a good pension. People like that just go into business.

    They're in it for the hunt, the dream, the achievement... the advancement.

    --

    Don't Bogart the fish sticks
  5. Interference by spin2cool · · Score: 3, Interesting

    But the weak nature of gravity means these disturbances are unimaginably small. . . One of the major tasks for engineers has been to insulate the installations from vibrations - from passing lorries and earthquakes - that might swamp the real data

    As a physics student, I know of many who question the reliablility of such instruments, especially when they're on the surface of the Earth. The earth's crust is composed of constantly moving, shifting layers of rock that create almost constant imperceptible geologic disturbances. It's nearly impossible to completely negate these.

    The scientists responsible for the experiments claim that the non-proximity of the two locations will negate any interference, but there is plenty of seismic data that shows that even the smallest tremors can be picked up by delicate equipment on the other side of the globe!

  6. Re:Insulation from vibrations noise... by Frans+Faase · · Score: 4, Interesting

    The idea is to find a place where there are not many fibrations and to make the system rigid. Movements parallel to the detector axis are (theoretically) not noticed. The remaining vibrations will simply make the instrument temporarily blind. That is no problem as long as they do not occur continiously. It is possible to distinguis between vibrations and changes in lenght. Using multiple instruments all over the world also helps distinquishing between local vibration events and globally caused changes in length due to gravational waves.

  7. Re:Insulation from vibrations noise... by sHu_pAc · · Score: 1, Interesting

    What really is going on is that, the scientists use both locations of the "sensors"(one located in washington, the other in new mexico I think). Were they found places that are relativelly quiet motion wise, use some really ingeneous ways of dampening out local noise, and when they think a gravity wave has moved the laser they check the other one that is located a couple states away and if this one has also moved in the same maner they have most likelly witnessed a gravity wave passing by. Also they obtain this precission from the rigidity of the laser mounts, they make these so that the lasers don't move at all but the supports absorb all the local outside motion of the earth (trucks going by, earthquakes, etc..) and theoretically a gravity wave supercedes all these and will be able to move the lasers therefore allowing a measurement. hope that helped

  8. Why not build one IN SPACE by A55M0NKEY · · Score: 1, Interesting

    They could launch a mirror into outer space. Send it off into the edge of the solar system. Then calculate where it 'SHOULD' be. They can do their lazer experiment by shooting a lazer at it from a sattelite and timing how long it takes to get back. They could shoot another sattelite off at 90 degrees to get their L shape and have as many of the sattelites as they need to get rid of noise ( which should be much less in space )

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    Eat at Joe's.