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New Interactive Black Hole Simulation Published
quaith writes "The New Scientist reports on a simulation just published in the American Journal of Physics that shows how the sky would appear in the vicinity of a black hole — if an observer could actually get near one. Using real positions of around 118,000 stars, the simulation shows how the bending of light, the frequency shift, and the magnification caused by gravitational lensing and aberration in the vicinity of the black hole affect the sky's appearance. The simulation is interactive and allows the user to explore the stellar sky around the black hole. The simulation offers a couple of modes: 'quasi static' or 'freely falling' and the sample videos are quite spectacular. The New Scientist has a writeup, with an embedded video . The original article citation is here (abstract only). The simulation, which runs on Linux or Windows, as well as sample videos, can be downloaded from the University of Stuttgart website."
does it...
which runs on Linux
Oh. sorry.
Why are they releasing that code? People are just going to try to find something wrong with it!
From TFwebsite:
The Department of Chronological Protection has spent so much of its efforts preventing the LHC from undergoing spontaneous gravitational collapse, that they forgot about the server in Stuttgart that actually did us in. Timothy, you've killed us all!
(Fortunately, I got a copy before the server imploded, so at least I know what to look for outside my window.)
The link is here, but the file is 262MB.
http://www.vis.uni-stuttgart.de/~muelleta/IntBH/DataDssBH.tar
Can someone set up a torrent?
how do you simulate it?
Whatever you do, for the love of all things good, Do Not invoke the simulation program with the -goatse switch....
email: b4024241@uggsrock.com
username: goatse
password: goatse
Alain Riazuelo at the Paris Institute of Astrophysics similar stuff years ago and even published a special DVD in a French magazine. It is sad they do not credit him at all, not very ethical.
http://www2.iap.fr/users/riazuelo/bh/index.html
is there really anyway to check the correctness of this?
If you make a blackhole joke on Slashdot, it needs to contain the words "suck" or "goatse"
What, they can't directly apply the compression methods they're simulating and create a 1byte file from the entire zip?
It's posted on Youtube here:
http://www.youtube.com/watch?v=uNc-JLysk9Y&feature=related
Watch 'til the end, the terminology is nothing short of cosmically hilarious.
Dave Lawson, astrogeek.
dot-sig.
I was expecting to see the stars distort and stretch as their image approached the black hole in the rotation movie. Instead, while they "realistically" move around the hole, we don't get to see the full effect of gravity's refraction.
This definitely qualifies as "News for Nerds".
The higher the technology, the sharper that two-edged sword.
In my eyes, in disposed, In disguise as no one knows
Hides the face, Lies the snake, the sun in my disgrace
Boiling heat, summer stench 'neath the black the sky looks dead
Call my name through the cream and I'll hear you scream again
Black hole sun
Won't you come
And wash away the rain
Stuttering cold and damp steal the warm wind tired friend
Times are gone for honest men and sometimes far too long for snakes
In my shoes walking sleep in my youth I prayed to keep
Heaven send, Hell away
__No one sings like you anymore__
Black hole sun
Won't you come
And wash away the rain
Hang my head drown my fear till you all just
Disappear
Black hole sun
Won't you come
And wash away the rain
thank you for setting the torrent
http://www.rentalgeek.com/downloads/ibhs.torrent
This has full data file, linux binary, and windows binary.
Also, this has been uploaded to Elbitz if you prefer private tracker.
Which is interactive, the black hole or the simulation?
50 replies already and not a single "your momma's so fat.." joke! Jeez!
Now that would be interesting; partly for the science, and partly because it would rile up the paranoid nuts.
Table-ized A.I.
...But all you have to do is create one to put the bin files in.
Strangely enough, it uses the same code library as the Fed Budget Simulator.
Table-ized A.I.
Here's a youtube vid dated 4/2009 that shows similar effects:
http://www.youtube.com/watch?v=3a2HqtH4aiE
Table-ized A.I.
...wow. Is it really not compressible, or did they not even try?
Don't thank God, thank a doctor!
It's called a light switch.
I would love to see the funding justification for this work. Not being snotty, I just want to know how to get research dollars for things that appear to have no practical purpose.
Here's another vid with trippy techno music and lots of event horizon distortion effects. Skip to the middle if you want to cut to the chase.
http://www.youtube.com/watch?v=SjsVvW-QlSI
Table-ized A.I.
Seems a bit of an over kill for a black hole simulation
I much prefer this bash one liner.
# while true; do clear ; done
It also sucks up the cpu for extra effect
I would hope for the sake of accuracy, the program completely freezes when the viewer hits the event horizon.
I assume the observer is just a normal one-eyed camera. What I don't get then is the way the distortion looks. I've just seen the vids. As you approach, the border of the blackhole starts to deform from the shape of a circle to something else. Top,bottom, left, right of it get flattened. How can that be ? The blackhole has the shape and symmetry of a sphere and if the view is centered on it, its border has to stay a circle, because neither that object nor the camera introduces some horizontal and vertical axis that works as a symmetry axis somehow for the deformed border that you see in that vid, when you get closer. There is nothing in that setup that introduces up, down, left, right, so imho that pic must have a rotational symmetry. Maybe someone can explain it. I'm just arguing with a bit logic&intuiton.
i used to have a nightmare where the sky would turn completely black because of a black hole. I would wake up sweating in the middle of the night and would freak out like a paranoid schizophrenic. This article does not make me feel any better
Time effects.
Your time would accelerate very fast, when you would approach the black hole. I would not be surprised if you would never ever actually reach the center. As time outside would become so fast, that you would see the (distorted) end of the universe before your eyes. If you would survive until then, that would be extremely cool though. Certainly a better way to die than slowly getting eaten by cancer.
Also I recommend having a radio stream coming in from the outside, so you could hear the acceleration (assuming radio receiver would survive). If you can get the outside sender to slow down the waves accordingly: Even better. Then you might soon get a message of who’s the next president, every 90 seconds. ;)
Any sufficiently advanced intelligence is indistinguishable from stupidity.
Most black holes are surrounded by an acceleration and (if the rotation direction of the black hole differs from that of the disk, a recent paper suggests) two jets at the poles. This makes the picture a whole lot less peacefull as given in this simulation. When approaching a black hole you probably die from radiation long before the stretching effect of approaching the event horizon.
If that's true, how can black holes grow at all? The time dilation effect would seem to suggest that nothing ever reaches the event horizon, because time slows down so it falls increasingly slowly towards the hole. Something must be wrong, because black holes can grow -- but what is it?
It ran on my laptops geforce 9100m /w 256mb shared memory, but fairly slowly. If you have a midrange videocard with only 256, give it a shot. Pretty neat simulation actually.....
zosxavius photography
Yet another proof of the Flying Spaghetti Monster!
The Tao of math: The numbers you can count are not the real numbers.
The explanation I've heard is that from the viewpoint of the outside universe, the matter falling into the black hole will stop radiating visibly at all, due to being red-shifted into nothingness, so it becomes indistinguishable from the black hole from both an emissions standpoint and a gravity standpoint.
I found that explanation vaguely unsatisfying.
Disclaimer: IANAL. This post is, however, legal advice, and creates an attorney-client relationship.
Well, the matter falling in has its own gravity as well.
For simplicity, let's assume that there's a perfectly symmetric shell of matter falling into the black hole, and for some strange reason it remains spherically symmetric (and I'll also assume a non-rotating black hole, which is also spherically symmetric). Remember that for spherically symmetric mass distributions, outside of the mass it looks exactly the same as if the whole mass were concentrated in the center.
Now, for this scenario, the whole space time looks like this:
So at the time the matter shell reaches the Schwarzschild radius of the complete mass distribution, which is larger than the Schwarzschild radius of the original black hole, a new horizon forms at that point.
Now with realistic matter distributions, it's certainly quite more complicated, but I'd guess that the fundamental growing mechanism is basically the same.
The Tao of math: The numbers you can count are not the real numbers.
Well that would happen at the event horizon, which by definition is the "edge" of the black hole anyway.
It's official. Most of you are morons.
im wondering why i can't see any red-shift in the videos...
any ideas?
... she swallowed a black hole?
This provides a way to perform a computation of infinite length within a finite interval (from your point of view). Of course, you have to count on the (external) universe sticking around and powering your machine forever, which doesn't fit with our current theories. You also have to launch yourself into a black hole to take advantage of this. Most users aren't ready to make that much of a commitment to one platform.
it has some pretty stiff hardware requirements!
Apocalypse Cancelled, Sorry, No Ticket Refunds
That black hole in the video looks almost exactly like Giedi Prime from Dune...
Slashdot's first reaction to VMware
#To avoid slashdotting, I've transcoded this simulation into a Web 2.0 application. Try it out now!
<html>
<body bgcolor=0>
</body>
</html>
When I run the simulation under windows, I just get this blue screen? Does this mean there is a small black hole in my PC?
Ross Youngblood
Clocks always run at the same rate in a given frame for an observer in that frame. It appears to take an infinite amount of time to an external observer. Hence the term "relativiity".
"I guess the moral of the story is, don't paint your airship with rocket fuel." -- Addison Bain
You have to think of spacetime as a malleable thing. You can end up inside the black hole before you fell into it. From your vantage point, you just fall in and quickly hit the center. During your journey, you cross over imaginary lines which represent the passage of time as recorded by an observer far from the black hole. When you start out far from the hole, you are crossing over each 1 second demarcation line every second on your clock ("proper second"). But the lines appear in increasing density nearer to the event horizon so you are suddenly crossing many seconds every proper second. You cross into time infinity, or the end of the black hole, whichever comes first, at the event horizon, ... but you don't stop there. You cross densely packed lines now going in reverse... you are ticking back seconds of observer time as you move closer to the center. You are moving back in time, in a sense. Finally, you crash into the center at a time close to when you started your journey.
So, from the observer's perspective: you are seen falling toward the black hole. You slow down as you get closer to the horizon. The black hole gets bigger as if you had been swallowed by the black hole but you are never seen to cross the horizon. There are now two copies of you in the timeline of the outside observer. One is asymptotically moving toward the horizon. The other is inside the black hole moving backwards toward the horizon. But the second copy can't be seen, only felt by the increased mass of the black hole.
The other frozen star theory is that black holes never fully form, but as matter accumulates, it asymptotically approaches the state known as a black hole. Eventually, it's indistinguishable from a black hole, although it never quite reaches the "ideal" black hole.