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BOINC Project to Search for Gravitational Waves
Buzz Skyline writes "Einstein@Home is a new, BOINC-based distributed computing project that will analyze data from the Laser Interferometer Gravitational wave Observatory (LIGO). The goal is to perform a whole-sky, gravitational wave survey of pulsars. Beta-test versions of the Einstein@Home screen saver should be available by the end of the summer, and final release is planned for early 2005."
So far, this would seem to be the 3rd BOINC project after Seti@Home and Predictor@Home.
"Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
Yes and that's what BOINC is, a generic framework for these types of tasks.
SETI@Home on BOINC
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
This is great to hear because it is believed that an advanced civilization would communicate not with radio waves but with gravity waves. Think about it: gravity waves fly right through anything, whereas standard EM waves are blocked by things like planets and dust clouds in space. This is why SETI@Home is a waste of time in my opinion after five years of constant computing and 3,000+ packets.
Of course, an advanced civilization using gravity waves would eventually switch over to some sort of sub-space/zero-point field communication system that could facilitate instant point-to-point communication between two points anywhere in the galaxy. Guess we'll have to wait for Subspace@Home.
Laser Interferometer Gravitational Wave Observatory? Who thought up that name? I bet he was responsible for the Illudium Q-Thirty Six Explosive Space Modulator too.
Banaaaana!
Yeah the jury is still out on the speed of gravity. I am worried that the speed of gravity is similar to that of light, or perhaps somewhat faster. But I am hoping that gravitational waves travel instantly throughout the galaxy. If so, then gravitational communication would be a highly desirable means of communicating between any two points in the galaxy.
The US Navy is right now studying using gravity waves to communicate to submarines underwater, although a URL with more information eludes me.
I am hoping someone resolves the issue of whether gravity travels at the speed of light or near it, or whether gravity travels instantly. The typical example is: if the sun disappeared right now, would Earth immediately hurl off into space, free of our orbit, or would it take 8.5 minutes for the loss of the gravitational field to be felt?
But perhaps the most interesting question of this entire thread could be: if gravity waves could be harnessed, could they be shielded too? I hope Podkletnov or Ning Li can find out! Anti-gravity here we come!
Scientific progress goes BOINC?
I work in physics research at the moment and when I first discovered distributed computing years ago I thought that eventually pretty much all research would end up using it. However, the problem with the seti@home model is that in order to get your user base you have to be doing a project that is 'cool' enough to get the attention of the public. 'We are looking for ET' is something that everyone understands and many people are interested in the possibility of alien life so you can get a large user base. Plus, it helps that the screen saver is perty! Trying to find a cure for cancer or AIDS is something else that would attract loads of people (in fact I remember taking part in such a DC project a couple of years back - dont know if its still going). However some projects would find it more difficult to attract the public. For example I am involved in modelling things called 'photonic crystals'. Now these things are very cool in my opinion but they take a bit of explaining to a non-physicist. In my experience - after I get started explaining them to any non-geek their eyes glaze over and they just dont care. Now I may be just rubbish at explaining stuff but I suspect (or is that hope??) that if you can't sum up your project as simply as 'The search for ET', 'Cure for Cancer' or 'Win 100,000 by finding a HUGE prime number' then getting computer power out of the public will be almost impossible. But then thats what the grid is for I guess.
Boinc should open up more distributed computing projects as well, since the server/client infrastructure is mostly prewritten. Since my other Boinc projects have been sputtering and not giving me work lately, maybe I'll give this one a try. More info on Boinc Here
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
For one thing, on most of the workstations BOINC would appear to work very quickly on the data only to crash out well before the computation was created. Indeed, sometimes it would actually crash before any data was processed by the application. At other points it would work for hours and hours without actually achieving anything; closing down the workstations at the end of the day without getting one computed dataset off was quite frustrating. On the workstations that were actually computing datasets we discovered a few started to become bloated past the point of peak functionality within a few months of even casual use.
While it's possible that it's the inhouse .NET code that could be creating the problem, after several weeks of debugging we're pretty sure it's BOINC related. My suggestion is to steer clear and look for a safer and more reliable API (or roll your own).
Try not. Do or do not, there is no try.
-- Dr. Spock, stardate 2822-3.
This is one of many projects related to GriPhyN (Grid Physics Network), an organized effort by physicists to bring important data analysis tasks to the home user. Distributed data analysis for LIGO is just one of the many projects that comprise GriPhyN; others include data analysis for the Sloan Digital Sky Survey and (I believe) the Large Hadron Collider, which is nearing completion at CERN in Geneva, Switzerland. SETI@HOME definitely caught the eye of physicists who, until recently, had been stymied by the lack of funds for supercomputers. While Linux clusters have gone a long way in addressing their needs, they quickly realized that the really data intensive applications such as LIGO, LHC, and SDSS would require something more. I'm excited that I might finally be able to change my screensaver to something other than SETI@Home!
With the average home computer advancing to higher levels, how long will it be until you can rent out your computer? I can imagine that it would be extreemly profitable to credit say $1.50 per hour of time running in the background of a program. Actually, paying for time is bad, paying for packets is better. Now I am not a trained professional in any way or form (I'll be a senior in HS next year) but I believe that paying people to compute should be cheaper then doing your own processing - and alot faster.
:-)
Most office computers in offices that I have been working in have relativly decent power and word processing doesn't take up much of their resources. Offices could make extra cash by running software in the backgrounds on their computers, if not during the day, then at night or after hours. Hrm, interesting possibilities
In nature, there are neither rewards or punishments, there are only consequences.
One of my colleagues likes to tease our students by referring to this volunteer grid stuff as "H-bomb@home". "Sure, your SW says it's doing gravity-wave calculations. I claim that USDoD is using it to do H-bomb (or bioweapon, or whatever) design simulations for free on your computer. Go ahead, prove me wrong."
IMHO it's an interesting point.
LIGO Hanfod is a very cool facility. I got to go on a tour of it several years ago while they were in the calibration phase. At the time they were working on mapping the background vibration in the area. Trucks hitting a bump on a highway over 10 miles away left a consistent detectable spike. It was impressive the work that went into identifying every vibration they felt and then setting up monitoring and periodic average noise maps in order to help filter out the background noise to focus on the vibrations from space. LIGO is the king of siesmographs.
:P, got to love America's fear of nuclear power.
Its interesting that LIGO Livingston seems to be the more PR focused one. Go figure the one in a worse location for this work, but not on a nuclear site gets the PR
If I remember right, there are 5 other international LIGOs, all collaborating on this. It's amazing the expense getting put into verifying this prediction by Einstein. It's never been clear to me why peopel care enough to go to such great lengths to verify this prediction. Anyone have insite in this? Please no philosophical boiler-plate answers...real impact-on-physics answers are what I am looking for.
Yet another version of AMOR... Talk about number of choices. For those who do not know: AMOR stands for Amusing Misuse Of Resources, its one of the toys for KDE.
Fight AIDS at home is just such a project.
While I agree that there are factors that prevent this from being used by everyone constantly, large-scale projects can often have a marketing twist put on them, or offer incentives. Additionally, an especially cool geek project would certainly pull a few volunteers. The important part is getting the awareness of the project to the proper audience, as the internet expands, I cant imagine a worthy cause not being able to find volunteers.
Scrame: Sunglasses are for assholes.
"Score 0 Redundant" ?????
Am I the only one here that finds this attempt at humor actually rather interesting. Given that my pocket calculator probably has more power than the computer system on the Apolo lander (please no debates on whether or not it happened) I can see this comment making a lot of sense for the future of high-powered computing.
Karma? Hey I just call it as I see it.
Millions of people run SETI@home every day, despite the power cost. I currently run three computers, two of which reboot once a week, and a laptop which I reboot once a night. I run seti on all of them and only turn it off when I need the best system performance for benchmarks or games. If there was an option for me to configure my software, so that I made a profit off seti, it would do nothing pay out. In order to target new consumers/users, the payout would have to be significant to bring in users and cover costs, but low enough not to bankrupt companies. I believe that this is all feasible and will be happening in the near future.
In nature, there are neither rewards or punishments, there are only consequences.
No. You'd have the effect before the cause would be visible. The cause, however, would still precede effect.
No, for at least some moving observers you do wind up with the effect preceeding the cause. It's all part of relativity. Two observers moving in opposit directions can dissagree about the order of two events. If anything exceeds the speed of light one of the observers will see the effect preceed the cause on the time line.
There is no such thing as "simultaneous", it's all relative.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
As written up at the back of Wired mag a few years back.
http://www.geo600.uni-hannover.de/
Picture two tubes, each exactly 600m long and at 90 degrees to one another in the horizontal plane. Bounce a laser beam off a mirror at the end of each one. The time should be identical. Unless there is a gravitational pulse, in which case one would appear shorter than the other.
Or maybe this is something completely different =)
No, I did not read the f***ing article!
Several companies have tried to create a commercial grid software setup that pays users for their contributions. None of them have taken off. They have trouble getting customers because they don't have an existing user base waiting to crunch. (It makes your sales a little more difficult when you can't say "We can get started immediately." Instead they have to say "If you pay us money, then we'll be able to go out start trying to get all those end users to sign up.")
The end users meanwhile don't want to sign up to run endless amounts of "test packets" that aren't accomplishing anything. (They obviously don't start getting paid until there's actually customers to crunch for.) It also doesn't help that these companies' software was also kind of bloated and quirky.
The lure of being able to materially contribute to real science, in areas that are typically underfunded, by donating only idle CPU cycles is quite strong. People will do that for free. The minute you start making them focus on it as a business venture, they start getting very picky and a lot less tolerant.
I don't think you're wrong, I think there will be some pay-to-crunch type systems existing in the future. But I think they will only be branches off an existing donated network (like Seti@Home). I really doubt anyone will be able to start one from the ground up as a business model. BOINC might be a place to start, but it would need some serious modifications.
For one thing, the BOINC credit system is based on what the end users' computers self-report. Each client software runs benchmarks of its CPU, and then based on the amount of time it took to finish a Work Unit, reports back to the server how many CS (credits) it should be granted. To guard against cheating, the server will send out the same Work Unit to 3 clients, and all 3 clients will only be granted the smallest number of credits of what the 3 individuals claim.
It will probably work well most of the time, because you have millions of users, and no real incentive for most of them to cheat. The probability of the same packet being sent to 3 different cheaters is fairly small. (And even if all 3 WERE cheaters and got more credits than they deserved, it doesn't REALLY matter, does it.)
But in a commercial setup, 100% of your end users have an incentive to cheat. (If you're getting paid $1.50 per credit, it's in every end users' interest to claim as many credits as you can get away with, regardless of how long it actually took.)
But regardless, I think distributed computing projects are going to be taking off dramatically in the next few years, paid or otherwise. It's going to be pretty exciting to see the kinds of crazy things people will start wanting to crunch with it.
Well folks, there you have it. Anonymous Coward has declared it so. No need for further discussion.
Stop all funding for gravity experiments and go back to making some more of those wonderful bobble-head dolls. I can't get enough of them!
Whats a photonic crystal then?
I can't believe you mentioned it and didn't then tell us. I would be happy to supply computer time for projects such as yours.
When I look for an DC project I look for one that fits the following criteria in this order of importance:
a)The results are published freely with no restriction on there use (so non-commercial basically - they can pay for computer time if they want it)
c)There is a linux version (preferably command line)
b)The software requires no user intervention (beyond maybe starting it)
d)The project looks like it is doing real science (this doesn't discount SETI@Home but I consider their chance of success low so I tend to steer clear of it)
You would be supprised how few projects fit all 4.
I used to have a better sig but it broke.
Right, but people were able to zap each other with electricity and make sparks and move compass needles and produce all sorts of other visible effects with electricity, even though they didn't understand the full nature of it. These new experiments are designed to try to detect gravity waves, because we haven't seen any evidence of their existence up until this point. (They've only be theorized.)
:-)
It's like saying the Navy is researching how to use the body of the Loch Ness Monster to power their aircraft carriers. Shouldn't the first step be to actually prove such a creature exists, and I don't know, maybe capture one too?? How far into your research can you really get when you haven't completed Step 1 yet?
If we can send a faster-than-light signal, we can exploit relativity to send signals into the past.
First, we need to realise that 'simultaneous' is a relative concept. Consider three evenly spaced spacecraft flying past you in a line. The centre ship fires lasers at the front and back ships, and when the beam reaches them they explode. Simultaneously? No: the lead ship is flying directly away from the beam, while the tail ship is flying towards it, so the ship at the back blows up first, and the ship at the front blows up later. But from the point of view of the captain of the centre ship? Both the other ships are stationary relative to him, so the beams reach them simultaneously.
In general, events that are simultaneous for one observer will not be simultaneous for an observer in relative motion.
Let us now suppose that we wish to cheat on the Alpha Centauri state lottery. At time t=0 in the frame of reference of Alpha Centauri the draw is made, and an instantaneous signal is sent to Earth with the result. The signal arrives at time t=0 (Earth is in the same reference frame, because it's not moving at any significant speed relative to Alpha.)
So, from the perspective of observers on Earth or Alpha, event A (signal sent from Alpha) is simultaneous with event B (signal received on Earth).
However, simultaniety is relative. Let us post an agent in a spacecraft moving at high speed relative to Earth and Alpha, such that from his point of view event A takes place after event B. This is quite possible, as we saw above in the example of the simultaneous shootings. Now when we receive our signal on Earth we relay it - instantaneously - to our agent, who then relays it - again instantaneously - to Alpha Centauri, allowing us to know the result of the lottery ahead of time and buy a guaranteed winning ticket.
Conclusion: instantaneous signalling buggers up causality.
Real Daleks don't climb stairs - they level the building.
Comment removed based on user account deletion
For a while I worked as a research programmer for one of the General Relative Groups working on the GEO600 Gravitational Wave Detector in both the UK and Germany. GEO600 is a UK and Germany co-project.
The interferometer is a typical Michaelson interferemoter using lasers with two orthogonal branches 600 metres in length. These gravitation events are small. Movements are ~10-E24 metres. It is expected that only one or two events a year will be detected. So it must run 24/7, 365 days a year.
Naturally you have to remove as much of the noise from the data as possible to detect an event. Mirrors are hung on glass threads as they are thermally inert. It runs in a vacuum. It is temperature controlled. Everything is monitored from air pressure to sisemology. The amount of data being produced is incredible. I assume LIGO is the same hence the distributed analysis.
GE0600 uses a microwave link to transmit data from the site to Hanover where it is backed up and fat pipes pass it on to partner universities. The 'head end' on site uses triple redundancy and enough bufferage for 24 hours back-up on site.
You are talking many gigabytes a day and many terabytes a year and some where in this lot will be an event. This is truely the domain of super computing or distributed processing.
Of course, even LIGO which is larger, is unlikely to spot many events if any and we will probably have to wait until LISA, the NASA/JPL/ESA spaced based interferometry project is up and running to get decent results.
The signal to noise ratio is suprisingly not bad here in /. on this so people must have some interest in it.
4 25 186202/qid=1089891363/sr=1-1/ref=sr_1_1/102-823243 2-3201747?v=glance&s=books
r av ity_waves_000727.html
There's a great book called "Einstein's Unifinished Symphony" that covers all this in great detail.
http://www.amazon.com/exec/obidos/tg/detail/-/0
The most likely thing to actually catch one is the proposed space based interferometer:
http://www.space.com/missionlaunches/missions/g
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
If A and B are simultaneous in your frame of reference, then A will be before B in frames of reference moving in one direction, and B will be before A in frames of reference moving in the opposite direction. So if you broadcast the result using an instantaneous communication device, then the recipient will get the result before the lottery is drawn - at least from some perspectives.
In your spaceship analogy that would be like having a ship blow up before the initial laser is even fired - that would seem impossible to me. I certainly see how order of events can be skewed by frame of reference, but I'm not sure that two events that occur in one order in one frame would appear out of order in another frame. I can see how their relative timing might differ - but not how they could pass each other.
The critical thing here is that the speed of light is the same in all reference frames.
So, in the frame of reference of the centre ship, beam A heads forwards at 300,000 km/s, and beam B heads backwards at 300,000 km/s. Since both ships are stationary, both ships are struck at the same time and explode simultaneously.
In the frame of reference of a stationary observer, in which the ships are cruising past at speed v, both beams are sent out at 300,000 km/s. The rear ship moves towards beam B at v and the front ship moves away, also at v, so the rear ship is struck first.
And in the frame of reference of a spy-ship flying at twice the speed of our warring convoy in the same direction, the three ships are moving backwards at speed v. Hence the front ship reverses onto the beam and the rear ship reverses away from it - and the front ship explodes first.
The wonderful part is that all three are correct. If two events are such that no signal travelling at lightspeed or slower can get from one to the other, then the order in which they take place is entirely dependent upon your point of view. That's why faster-than-light communication leads to madness...
Real Daleks don't climb stairs - they level the building.
That said, looking at the LIGO facility , it seems like somewhat of a harsh scar on the Louisiana forest. Could they not have been a little 'greener' in their construction of the site? One of their daily secondary missions, after all, is educating students.
In a bit of my research into gravity in general, the discovery and eventual understanding of gravity (waves or whatever they are) would me the most momentous discovery of science in the last 500 years. The eventual ability to alter and manipulate this natural force could mean a lot to science and everyday life. Some suggest that gravity, unlike light, is INSTANTANEOUS. Meaning that its effect is not time measurable, its force propagates throughout the universe everywhere instantaneously. Imagine the possibilites for communications, travel etc... is this proved to be true...
Allow me to point you to Folding@Home. This is Stanford's distributed computing project. Their goal: to understand protein folding, protein aggregation, and related diseases.
I'm sure they've been mentioned before, but they seem to meet your four criteria nicely:
a) The second question in their FAQ is "Who owns the results"
c) A Linux Console version is listed on theirDownload Page along with Windows and Mac OS X versions.
b) In my experience, I've had to do nothing but install and let the software do its thing. It only takes up unused cycles and is completely non-intrusive. For Mac OS X users, I recommend checking out TeamMacOSX's website for some free software downloads that make it easy to maintain clients for multiple processors.
d) Science!
SharkJumper
The US Navy actual does a lot of research of gravity waves, however they are referring to a slightly different definition or nature. Instead they are looking at periodic influences of tides and other aspects of gravity. For example, examining the effects of "gravity waves" on the atmosphere. It also doesn't help that a component of surface waves on the ocean are also called "gravity waves" since these are waves that are working against gravity. A google search shows the stuff does show up in a lot of Navy research documents, and would probably be pretty confusing if it doesn't give enough information to hint it is not the same gravity waves talked about here.
There has been a few popular discussions of gravity wave (in the normal sense) communication, including a short blurb in several magazines that I recently remember referring to a paper about converting electromagnetic waves to gravity waves. I'm skeptical of what is proposed, but it doesn't take too much equipment to test, so I wouldn't be surprised if other people were testing it. Although there is no explicit mentioning of the Navy in any of that I remember.
Spacetime diagram doesn't work out for this one, unfortunately... Think of a light-cone centered on Earth and another one centered on Alpha - they cross at a point a few years in the future (and physically at the midpoint between the two systems). So, yes, if Alpha draws a lottery, and sends the info to Earth instantaneously, the Earthlings have it a couple years before the light of the lottery-drawing event reaches Earth.
However, they turn around and beam the message back to Alpha Centauri. Time has still passed (even a miniscule amount of time, if they had an auto-receive/reply machine on Earth that takes the beam from A and turns it around immediately to send back). When the message is received at Alpha Centauri, it's received *after* the drawing took place, and *after* they sent the message to Earth. However, they're receiving it several years before they would know that the Earthlings would normally know about the result - so it seems like the Earthlings are "predicting" the lottery, but they're always telling the answer just a little too late.
In any case, the spacetime diagram in this instance works better if you take it as a generic... The 45-degree lines in an ordinary diagram represent light-speed. However, if you're including infinite-speed gravity waves as a method of transmitting data, then your "cone" has to open up to 180-degrees: every event, no matter how distant, that happens simultaneously can be known to everyone, no matter how distant. And no problem with causality, just that light is too slow to keep up with "real-time".
Highly unlikely, though - there are bigger problems than causality in relativity that constrain information (not just light) to travel no faster than light.
-T
finally! ^_^
:-)
*remembers that Dr. Zefram Cochrane (ST) was born in 2030
The term "gravity wave" is used in hydrodynamics to refer to large waves at fluid boundaries which are governed exclusively by inertia and gravity. For example, your typical ocean wave. This is as opposed to a "capillary wave" which is governed at least partially by the effects of surface tension and cohesion. In water, the transition from gravity to capillary wave behavior occurs somewhere around a wavelength of 5 cm.
It's quite possible the Navy is doing some kind of research with gravity waves, but whatever it is, it's probably not for long distance communication because the waves move so slowly and their long wavelengths make them hard to focus.
That's what the BOINC project is all about.
Software piracy is victimless theft.