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NASA Scientists Simulate Black Hole Collision
Krishna Dagli writes to tell us Yahoo! News is reporting that NASA scientists have managed to simulate the merger of two massive orbiting black holes. Using technology from Silicon Graphics, Inc. built from 20 SGI Altix systems the team was able to show how the resulting gravitational waves would interact with surrounding space.
cut this signatures madness. stop reading them now!
imagine a beowolf.... nevermind :)
Man, that would suck.
The first video is looks pointless. It just shows two black holes circling around each other doing nothing, and then the clip just ends. Einstein's clip shows two black holes merging into one big-ass black hole, which shows a much more interesting theory than "nothing really happens when two black holes meet, but here's a video anyway!"
Boom!...?
Error 2101: all your sig are belong to us
I wasn't aware that we understood how one black hole worked so how can this team perform a simulation of two coming together and hope to get anything useful out? I admit there is an outside chance they will stumble on the correct result but can they prove it's correct?
I used to have a better sig but it broke.
Only to idiots, are orders laws.
-- Henning von Tresckow
Now lets do it for real.
If this were really happening, what would you think?
Your sig just a moment ago said "404 error: sig not found". Now it says simply "sig not found". I was just now going to suggest changing it to "404 error: sig not found. Additionally, a 404 error was encountered why trying to locate an errordocument".
The date on the Nasa page is 18 April.
That's good to know, in case one is ever caught in the middle of two colliding black holes and you need to figure a way out of that sticky situation....
Hey champ: NASA is about real research too, not just strapping yourself to rockets and aiming for the nearest rocky, spherical object.
By having two NASA scientists smashing their butts against each other?
I actually went to a seminar years back by one of the individuals working on this. The equation alone filled pages, and was something he had to derive by hand. He showed us a cgi video of the results. The 2 black holes approached, snapped together, and the resulting larger black hole temporarily oscillated. The strange part was partway through the oscillation, the black hole just popped out of existence, and then reappeard several seconds later.
In the question and answer period, a student asked why this gap in the calculations. The professor explained there was no gap in the calculations, but rather, the result of the calculations was non-euclidean in nature, so it was physically impossible to display it in a 3d model. At about that time, half of the undergrad audience whispered a Keanu Reeves style "whoah..."
Don't ask me any of the details, this was years ago in a course on stellar astrophysics that I have mostly forgot. This is just something anecdotal. Astrophysicists have been working on this black hole merger thing for a very long time. The computer labs at the time had P133's running. I'd love to see what they're doing now, but that site wasn't very big on actual information.
I went through the videos on that site I missed. I could swear I saw the EXACT SAME videos at the 1993 conference. Especially the one that showed the gravity waves of the two merging black holes. I swear I even see the resulting black hole wink out for a frame or two. They really don't show the actual merger in very much detail at all, I think this is on purpose. I think that's why they havn't posted anything that clearly shows the merger, because I very much doubt an observer at the merger of 2 black holes would just see it wink out of existence like that. (Not that an observer would survive that kind of event, but that's neither here nor there.) For public release I guess it's bad to admit they don't have all the answers yet.
This is new news?
...
This article and movie was featured in New Scientist on 4.18.06.
Black holes collide in the best simulation yet
18:29 18 April 2006
NewScientist.com news service
Enlarge image
Black holes distort space-time (yellow lines) and emit gravitational waves as they spiral towards each other (Image: Henze/NASA)
Enlarge image
Simulations of the ripples in space-time produced when two black holes merge could help astronomers interpret future gravitational wave observations (Image: Henze/NASA)
The ripples in space-time created when two black holes merge have been modelled to unprecedented accuracy, according to Einstein's equations, by a powerful new computer simulation. The "waveform" signatures produced in the simulation should help researchers identify the ripples in the data from gravitational wave detectors.
Powerful gravitational waves are thought to shake the fabric of space-time when two black holes spiral towards each other and eventually merge. The waves have not yet been observed, but researchers have been trying to simulate the process on computers in order to predict the expected signal. That will help the nascent searches now in progress.
The signals, called "waveforms", are shaped by factors such as the frequency at which the two black holes orbit each other, their relative masses and their spins. But modelling the merger has proven exceptionally difficult because the process is governed by Einstein's theory of general relativity.
"People have been trying for years to follow the coalescence of two black holes where you treat general relativity exactly," comments David Merritt, an astrophysicist at the Rochester Institute of Technology in New York, US.
John Baker of NASA's Goddard Space Flight Center in Greenbelt, Maryland, US, agrees. "Part of the complexity of simulating Einstein's equations are the equations don't come in a unique form," he told New Scientist. "You have a lot of choices to make when you approach the problem."
- Zav - Imagine a Beowulf cluster of insensitive clods...
The arxiv.org original paper can be found here. From what I understand of the original paper, they only did a non-rotating black holes. This paper is a significant step forward in numerical relativity because they were able to actually get information out about the gravitational waves that carry the energy away from the two black holes and allow for the inspiral to happen.
As mentioned in the paper, a lot of previous work has been done on this problem. Up to this point, one of the methods used was a circular orbit approximation.
The detection of gravitational waves will be a huge step forward for General Relativity and these simulations are very important for the groups doing the data analysis like the LIGO Scientific Collaboration Group at the University of Wisconsin-Milwaukee who work on the data analysis of the scientific runs from LIGO. It allows them to test their detection algorithms more accurately so that when(if) they detect an event, greater confidence can be given about the detection.
a reference to John Titor?
for the uninitiated: http://www.johntitor.com/
*and apparently the prev dup article as well, but I could've been wrong.
2^3 * 31 * 647
http://www.nasa.gov/centers/goddard/universe/gwave .html
I read the title as NASA Scientists Simulate BackHoe Collision...
Hoek on phoniks woerk for me!
No, seriously, I just come here for the articles.
It's like, how much more black could this be? and the answer is none. None more black.
The Rise and Fall of Online Community
so I have a few problems with this type of article.
first off, the result is an obvious PR piece for SGI. Such a slant taints the reason for the piece - making it impossible to really judge the significance of the computation. The contactacts ARE the SGI PR folks.
next, the article frames this an achievement in simulation that was "made possible" by the computer. This framing shows the lack of understanding about simulation by the author. In all computer simulation, there is a tradeoff between realism/accuracy and what is possible computationally. There is no hard line beyond which you get to claim, "this was a "realistic" simulation" as they do - especially for black holes, which we have almost no measurements. There is always tremndous guesswork and tradeoff that have to be made.
I tend to wonder if the computer scientists who built the system had much input on this article. I would guess not.
I wonder how many computers you could buy with $2 trillion dollars. Heck, you could buy a PC for everyone in the world with that kind of money.
I think I'd want a PC that can do more than what $333.33 would buy.
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
Wow, they must've spent nearly $2000 on all those SGIs on ebay.
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Kids dont need better computers at school, i would go as far to say, they need less computers because they are largely unused as it is. A computer in every classroom was the greatest scam of the 90's
The phrase "more better" is acceptable English. suck it grammar Nazis
No expert here, but I do recall reading some commentary about string theory predicting multiple universes. The potential importance of this research is that gravity waves may be the only way to communicate between multiple universes!!!! (unless T-mobile installs some new cell towers in the other universes). Understanding and detecting them could lead to some future communication revolution.
how is this offtopic? because I didn't state that john titor talks about the use of two micro black holes to travel through time?
2^3 * 31 * 647
This is nice and all, i mean im glad to see great minds working together but this just didnt interest me that much because of how little we know about black holes.
anyways thats just my opinion
I'm not yet qualified to have a sig