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New Interactive Black Hole Simulation Published

timothy posted more than 4 years ago | from the watch-for-these-danger-signs dept.

Space 107

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."

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yes, but (5, Funny)

Anonymous Coward | more than 4 years ago | (#31132058)

does it...

which runs on Linux

Oh. sorry.

Yes, but... (2, Interesting)

2.7182 (819680) | more than 4 years ago | (#31132218)

is there really anyway to check the correctness of this?

Re:Yes, but... (3, Interesting)

shaitand (626655) | more than 4 years ago | (#31132254)

The actual correctness? no. and there probably never will be.

I'm sure physics geeks will be heartily debating the THEORETICAL correctness any minute now. After all, what else would they be doing on a saturday night

Re:Yes, but... (5, Funny)

blindseer (891256) | more than 4 years ago | (#31132462)

After all, what else would they be doing on a saturday night

Posting on Slashdot?

Re:Yes, but... (1)

nicknamenotavailable (1730990) | more than 4 years ago | (#31132488)

I'm sure physics geeks will be heartily debating the THEORETICAL correctness any minute now. After all, what else would they be doing on a Saturday night.

Stargate Marathon!!! YEaaaaah....

Re:Yes, but... (2, Informative)

iluvcapra (782887) | more than 4 years ago | (#31132816)

IANAP, but I seem to recall that images that depict gravitational lenses tend to show stars near the lens deforming into arcs; in this movie stars in the background remain points, even though at least some of them would deform into arcs as they passed behind the object.

Re:Yes, but... (1)

amRadioHed (463061) | more than 4 years ago | (#31133352)

The images of gravitational lensing typically show galaxies deforming into arcs, I'm not sure about stars. Stars are effectively point sources in even the best telescopes, so that may make a difference.

Re:Yes, but... (1)

TheLink (130905) | more than 4 years ago | (#31134836)

How about light from stars to the side (and other directions) of the object and not just behind?

Re:Yes, but... (1)

Chris Burke (6130) | more than 4 years ago | (#31135162)

IANAP, but I seem to recall that images that depict gravitational lenses tend to show stars near the lens deforming into arcs; in this movie stars in the background remain points, even though at least some of them would deform into arcs as they passed behind the object.

Not necessarily, see Einstein's Cross [wikipedia.org] .

Also, watching the video on the New Scientist, stars definitely do get distorted and stretched around the black hole, just not into the large arcs you'll often see in pictures of gravitational lensing taken from our vantage point.

I'd wager most of the difference between the simulation and what you're expecting to see comes from where it's located, which is much nearer a source of lensing than we have the good fortune of being close too.

Re:Yes, but... (4, Informative)

HeronBlademaster (1079477) | more than 4 years ago | (#31133280)

After all, what else would they be doing on a saturday night

How about playing Star Trek Online on one monitor while watching Farscape (via Netflix) on the other monitor?

Re:Yes, but... (1)

Tim C (15259) | more than 4 years ago | (#31133668)

Well, I was drinking and watching Quarantine on Saturday night - today's Sunday in my time zone :)

Re:Yes, but... (1)

Zumbs (1241138) | more than 4 years ago | (#31133844)

I'm sure physics geeks will be heartily debating the THEORETICAL correctness any minute now. After all, what else would they be doing on a saturday night

Obligatory xkcd [xkcd.com] .

Re:Yes, but... (1)

raving griff (1157645) | more than 4 years ago | (#31132390)

Well, there's always the LHC... ;)

Re:yes, but (1, Funny)

Anonymous Coward | more than 4 years ago | (#31132238)

I was so afraid to click, worried whether it was Goatse. But my fears were naught. However, what is Rick Astley doing orbiting around a black hole?

Re:yes, but (0, Redundant)

outsider007 (115534) | more than 4 years ago | (#31132716)

maybe if the black hole was on uranus...

Re:yes, but (1)

theshowmecanuck (703852) | more than 4 years ago | (#31134658)

It said the colour values were in sigma.bin NOT sigmoid.bin [wikipedia.org]

Re:yes, but (1)

Tablizer (95088) | more than 4 years ago | (#31132584)

Very good, now show us what hot grits look like being sucked into a blackhole.

hardware requirments (1)

budgenator (254554) | more than 4 years ago | (#31134948)

System requirements

        * At least 300MB GPU memory.
        * The Linux version needs the free Qt SDK which can be found here.

The application was tested with the graphics boards: NVidia GeForce 8600 GT, ATI Radeon HD 3800.
Distortion of the stellar sky by a Schwarzschild black hole, [uni-stuttgart.de]
Thomas Müller, Daniel Weiskopf

it has some pretty stiff hardware requirements!

why? (4, Funny)

Anonymous Coward | more than 4 years ago | (#31132088)

Why are they releasing that code? People are just going to try to find something wrong with it!

Re:why? (0)

Anonymous Coward | more than 4 years ago | (#31133490)

Well, from the first look of it, it has a big security hole...

Available? Not for long. (1)

Tackhead (54550) | more than 4 years ago | (#31132118)

The simulation, which runs on Linux or Windows, as well as sample videos can be downloaded from the University of Stuttgart website.

From TFwebsite:

The following data files have to be stored in the 'data' directory of the application:

# Distortion array for the region above the horizon: array_outside.bin (binary data file, 128MB).
# Distortion array for the region below the horizon: array_inside.bin (binary data file, 128MB).
# Integral psi_V as a function of temperature: psitemp.bin (binary data file, 2.1kB)
# Color values Sigma_j: sigma.bin (binary data file, 3.1MB)
# Hipparcos catalogue: hip.bin (binary data file, 2.8MB)
# All these data files can also be downloaded as one single tar-file (262MB). [emphasis added]

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.)

What's an Interactive Black Hole and ... (0)

Anonymous Coward | more than 4 years ago | (#31132154)

how do you simulate it?

LHC Armageddon Sim (1)

Tablizer (95088) | more than 4 years ago | (#31132622)

Now that would be interesting; partly for the science, and partly because it would rile up the paranoid nuts.

Re:LHC Armageddon Sim (0)

Anonymous Coward | more than 4 years ago | (#31132880)

Here ya go:

http://www.youtube.com/watch?v=M3iMX8xzofc [youtube.com]
 

No compression? (1)

SanityInAnarchy (655584) | more than 4 years ago | (#31132742)

...wow. Is it really not compressible, or did they not even try?

Re:No compression? (1)

SanityInAnarchy (655584) | more than 4 years ago | (#31132794)

Apparently, they didn't even try. The fastest compressor I know, lzop -1, shaves off almost 40 megs. The best one I know that we could reasonably expect people to have is lzma (included by default on Debian systems), and that cuts the file in half -- more than -- from 262 megs to 111 megs.

I hope the university has gzip compression enabled, but either way, whoever did this is wasting more than double bandwidth of their university in a slashdotting because they couldn't be bothered to compress files. WTF?

Link, needs torrent. (1)

paul248 (536459) | more than 4 years ago | (#31132152)

The link is here, but the file is 262MB.
http://www.vis.uni-stuttgart.de/~muelleta/IntBH/DataDssBH.tar [uni-stuttgart.de]

Can someone set up a torrent?

Re:Link, needs torrent. (2, Interesting)

paul248 (536459) | more than 4 years ago | (#31132206)

Well, I'm at 155/262MB currently. I'll create the torrent myself when it's done (~ 11 minutes)

Re:Link, needs torrent. (1, Informative)

Anonymous Coward | more than 4 years ago | (#31132264)

why.. your link was a 1.2 minute download

Re:Link, needs torrent. (0)

Anonymous Coward | more than 4 years ago | (#31132338)

It took >20 minutes for me. Maybe their link to the US is slow?

Re:Link, needs torrent. (4, Informative)

paul248 (536459) | more than 4 years ago | (#31132306)

mod parent up (0)

Anonymous Coward | more than 4 years ago | (#31132470)

thank you for setting the torrent

Re:Link, needs torrent. (1)

SanityInAnarchy (655584) | more than 4 years ago | (#31132764)

The original server isn't doing too badly, so I'm using it as a webseed. I don't know how hard that would be to bake into the torrent itself...

Warning! (3, Funny)

fuzzyfuzzyfungus (1223518) | more than 4 years ago | (#31132156)

Whatever you do, for the love of all things good, Do Not invoke the simulation program with the -goatse switch....

Re:Warning! (0)

Anonymous Coward | more than 4 years ago | (#31132252)

I was actually thinking more along the lines of "Before you die, you see the Ring."

Re:Warning! (0)

Anonymous Coward | more than 4 years ago | (#31132468)

it's --goatse, or -g as a short option. -goatsie would actually invoke -g(goatse) plus -o (Oprah), -a (asshole), -t(tits), -s(sex), -i(inbreeding), and -e(excrement). I dunno about you, but I'd try my damnest to escape that black hole. Screw event horizons!

Re:Warning! (0)

Anonymous Coward | more than 4 years ago | (#31132476)

My god, it's full of stars!

Re:Warning! (1)

Tablizer (95088) | more than 4 years ago | (#31132590)

Do Not invoke the simulation program with the -goatse switch

Actually, they are very similar such that one may not tell the difference.
   

login (0)

Anonymous Coward | more than 4 years ago | (#31132180)

email: b4024241@uggsrock.com
username: goatse
password: goatse

Not new (2, Informative)

Anonymous Coward | more than 4 years ago | (#31132182)

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

Re:Not new (3, Informative)

Radtoo (1646729) | more than 4 years ago | (#31133038)

Not ethical? Why should this person be credited?
Is the program code taken from Alain Riazuelo, or did he perhaps invent the theory behind Black Holes that made it possible to write the program from the article?

Because what is asked in research is only that the persons whose work the current publication is based on are credited, both for the sake of their achievement and to enable verification of theories that isn't only superficial (current publication).

Re:Not new (3, Insightful)

gardyloo (512791) | more than 4 years ago | (#31133462)

Perhaps, but it's common (and, I would argue, right) to mention work which has gone before, whether or not it was exactly the same. It gives alternative routes of learning about the given subject (which is, after all, the whole point of publishing results in the first place, right?). Sure, if the work isn't immediately applicable, then do it in a footnote or appendix, but unless one is totally unaware of the previously published (or even unpublished) work, it's better to be comprehensive than parochial.

Re:Not new (0)

Anonymous Coward | more than 4 years ago | (#31133600)

Have you considered that, possibly, the authors were totally unaware of the previously published work? It's absolutely normal in academic circles for people to put out a paper, and then be bombarded with a thousand emails from other researchers in *exactly the same field* asking for citations. Most of those emails are absolutely spurious, but some of them are quite valid. There's just so much literature that no-one can be expected to know it all, and we'll always overlook other research, even when it's exactly in our own focussed area. It isn't "sad" or "unethical" that they didn't cite him -- that immediately presupposes that the Stuttgart researchers deliberately didn't cite him. And that, my friend, is an extremely serious claim and it's rather sad that you would leap to that conclusion.

Furthermore, for all I know -- not speaking French, much like the vast, vast majority of researchers -- this DVD of his actually has a totally different focus to their work and does something very different. Maybe it doesn't, maybe it's on an identical basis. I can't tell.

Re:Not new (1)

Jesus_666 (702802) | more than 4 years ago | (#31133894)

Of course it's possible they are unaware of the previous work.

People on slashdot.... (0, Offtopic)

zerospeaks (1467571) | more than 4 years ago | (#31132204)

The people on slashdot don't want to here insightful or informative comments. They just want to hear what they agree with. So I will just make a half attempt at a joke. I for one welcome our new singularity condition calculating overlords.

That sucked (0, Offtopic)

Anonymous Coward | more than 4 years ago | (#31132240)

If you make a blackhole joke on Slashdot, it needs to contain the words "suck" or "goatse"

Re:That sucked (3, Funny)

stokessd (89903) | more than 4 years ago | (#31132540)

This is how you do it:

I just downloaded the simulation and the first thing it printed was:
"It is pitch black. You are likely to be eaten by a black hole"

Re:That sucked (1)

maxwell demon (590494) | more than 4 years ago | (#31133590)

I'm running the simulation right now, simulating falling into the hole. I must say, it's very realistic. I eevveenn eexxppeerriiieeennnccceee ttttiiiimmmmeeee ddddiiiiilllllllaaaaaaaaaaaaaNO CARRIER

Re:That sucked (0)

Anonymous Coward | more than 4 years ago | (#31133946)

Ah, yes! The SpaceHack is finally born! ..Oh, wait..

Re:That sucked (0)

Anonymous Coward | more than 4 years ago | (#31132724)

But seriously though, when I looked at the model time slowed down, the big dipper stretched out and got sucked into Uranus.

Sloppy programming (2, Funny)

AnotherAnonymousUser (972204) | more than 4 years ago | (#31132242)

What, they can't directly apply the compression methods they're simulating and create a 1byte file from the entire zip?

Re:Sloppy programming (2, Funny)

Megane (129182) | more than 4 years ago | (#31132360)

Here it is in hexadecimal: 2A

Blessed Atheist Bible Study (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31132244)

Have you guys been to the blessed atheist bible study. He's newn but he's funny. He has a great rant against young earth creationism. Check it out at http://blessedatheist.com/

Neil deGrasse Tyson's explanation of falling in: (5, Interesting)

dlawson (209945) | more than 4 years ago | (#31132266)

It's posted on Youtube here:

http://www.youtube.com/watch?v=uNc-JLysk9Y&feature=related [youtube.com]

Watch 'til the end, the terminology is nothing short of cosmically hilarious.
Dave Lawson, astrogeek.

Re:Neil deGrasse Tyson's explanation of falling in (1)

Tablizer (95088) | more than 4 years ago | (#31132668)

Here's a youtube vid dated 4/2009 that shows similar effects:

http://www.youtube.com/watch?v=3a2HqtH4aiE [youtube.com]
   

Re:Neil deGrasse Tyson's explanation of falling in (1, Interesting)

Tablizer (95088) | more than 4 years ago | (#31132806)

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 [youtube.com]
     

Re:Neil deGrasse Tyson's explanation of falling in (1)

maxwell demon (590494) | more than 4 years ago | (#31133606)

Yet another proof of the Flying Spaghetti Monster!

Not exactly as I expected (1)

Deorus (811828) | more than 4 years ago | (#31132302)

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.

Well, if nothing else ... (2)

ScrewMaster (602015) | more than 4 years ago | (#31132408)

This definitely qualifies as "News for Nerds".

Black hole Sun (2)

masmullin (1479239) | more than 4 years ago | (#31132410)

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

TORRENT (4, Informative)

shaitand (626655) | more than 4 years ago | (#31132508)

http://www.rentalgeek.com/downloads/ibhs.torrent [rentalgeek.com]

This has full data file, linux binary, and windows binary.

Also, this has been uploaded to Elbitz if you prefer private tracker.

Re:TORRENT (1, Funny)

Anonymous Coward | more than 4 years ago | (#31132924)

Excellent!
Thanks to these naive coders, I am now one step closer to my black hole machine!
Igor! Bring me my laughing flashlight! Muahaha!

Which is interactive? (1)

Subm (79417) | more than 4 years ago | (#31132520)

Which is interactive, the black hole or the simulation?

I can't believe this! (1)

Superdarion (1286310) | more than 4 years ago | (#31132576)

50 replies already and not a single "your momma's so fat.." joke! Jeez!

Re:I can't believe this! (-1, Flamebait)

Anonymous Coward | more than 4 years ago | (#31132682)

your momma is so fat it takes a beowulf cluster to do the same.

Yo momma so fat ... (0)

Anonymous Coward | more than 4 years ago | (#31134176)

... she swallowed a black hole?

No Data Directory in Windows Version (1)

mbunch5 (548430) | more than 4 years ago | (#31132626)

...But all you have to do is create one to put the bin files in.

Re:No Data Directory in Windows Version (1)

Anonymous Coward | more than 4 years ago | (#31132796)

It still doesn't work after that.

Re:No Data Directory in Windows Version (1)

netflix (1367097) | more than 4 years ago | (#31133566)

Yeah this doesn't work for me either. Anybody have any ideas?

Re:No Data Directory in Windows Version (1)

linest (157204) | more than 4 years ago | (#31135822)

I know this is going to sound like a troll, BUT...

I compiled the Linux version and untarred the data tar file. It worked.

I downloaded the Windows version and created a data directory and put the data files in there. Nope, doesn't work.

Deficit anyone? (1)

Tablizer (95088) | more than 4 years ago | (#31132634)

Strangely enough, it uses the same code library as the Fed Budget Simulator.

I've had a black hole simulator for years. (0)

upuv (1201447) | more than 4 years ago | (#31132760)

It's called a light switch.

Why was this done? (1)

cyn1c77 (928549) | more than 4 years ago | (#31132802)

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.

Re:Why was this done? (4, Informative)

Legion303 (97901) | more than 4 years ago | (#31133046)

I imagine you would first have to move to Germany, then get a job at the University of Stuttgart. Then ask the German government for funding before someone reminds you that universities provide their own funding and usually don't require much justification for the research they choose to produce.

Re:Why was this done? (1, Insightful)

Anonymous Coward | more than 4 years ago | (#31133174)

WTF? I would have thought you weren't being serious, except for your "not being snotty" comment.

A lot of science is already thick with impenetrable equations and difficult papers that, while perhaps containing significant results, are read and understood by, at best, several dozen others who are also in the field.

Sometimes the best way to understand something is with visualization. And visualization can be one of the best ways of getting people interested in a field. There will be students that see this and ask, "why" and "how". And some of those might go on to study physics or cosmology. And perhaps that leads to a big discovery somewhere down the line.

I, personally, found it extremely interesting. I've often wondered about the inner workings of a black hole. But to really understand from the equations means years spent at study of the field. I have a job now so no longer have that kind of time to pursue a subject. Seeing this animation answered some of my questions and gave me things to think about.

Re:Why was this done? (0)

Anonymous Coward | more than 4 years ago | (#31133642)

All of this. (Except I've experience in it so I've done at least some study into the inner workings of a black hole. But I'm no specialist so I still found it very interesting.

"A lot of science is already thick with impenetrable equations and difficult papers that, while perhaps containing significant results, are read and understood by, at best, several dozen others who are also in the field."

Haha, very true. I've spent the last three years focussing on a small area of physics which is considered by perhaps another 20 people in the world. I could probably name them, and I've met (and pissed off) basically all of them. I've just moved to a new university and gave a seminar the other day on this topic. This is a good university, and a good department, and there was maybe one guy in the room who followed most of what I was saying. Not so much because he's done it before, but because he's done more general relativity than the rest of them. And *he* still didn't follow everything either.

Of course, I'd not necessarily claim my results are all that significant, but I can fully vouch for the rest of this statement.

[Anonymous for obvious privacy-protecting reasons.]

Re:Why was this done? (1)

maxwell demon (590494) | more than 4 years ago | (#31133744)

I can assure you that no single research dollar has gone into this. It's all payed in euros.

Re:Why was this done? (0)

Anonymous Coward | more than 4 years ago | (#31134126)

"...no practical purpose."

That's probably one of the most disingenuous things I think I've read on /. Most of the useful discoveries of the last century started out as "what would happen if..." questions and without practical purposes in mind. No one could have predicted the uses of the laser at the time it was invented ("we have this thing and it's really cool, but we dunno what to do with it"). It's called "pure research" and it's vital for scientific and technological advancement.

Re:Why was this done? (0)

Anonymous Coward | more than 4 years ago | (#31134206)

I would love to see the funding justification for quantum physics in the beginning of the 20th century. Not being snotty, I just want to know how to get research dollars for things that appear to have no practical purpose.

Until 50 years later that is, when pretty much all of modern technology relies on that purely theoretical research. You know, semiconductors and fiber optics and all that. Just because there is no practical reason now doesn't mean there never will be, and there's no good way of knowing which theoretical research will end up being the basis for the next century of technological improvement.

People often forget the importance of basic science research these days, instead focusing on what can be immediately profitable. It's the difference between long-term and short-term planning, and in an era of quarterly profit returns and intense media focus, there is sadly a severe lack of the former.

Can be done in bash (0)

Anonymous Coward | more than 4 years ago | (#31132986)

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

Re:Can be done in bash (1)

maxwell demon (590494) | more than 4 years ago | (#31133644)

It also sucks up the cpu for extra effect

In other words, it simulates time dilation (your computer gets slow).
However, your script doesn't do a very good job at it, and completely fails with multicore CPUs.

Here's a better script:

#! /bin/bash
while true; do $0& clear; done

Does the program freeze at the event horizon? (1)

caywen (942955) | more than 4 years ago | (#31133018)

I would hope for the sake of accuracy, the program completely freezes when the viewer hits the event horizon.

Re:Does the program freeze at the event horizon? (1)

boristhespider (1678416) | more than 4 years ago | (#31133658)

The observer only freezes at the event horizon as viewed from asymptotic infinity. From the point of view of the observer themselves there's nothing special happens at the event horizon -- it just looks like normal space. (It's a basic tenet of general relativity that you can always remove the effects of gravity locally; that's why singularities are such a problem, because the theory itself breaks down. If an event horizon *did* fuck up for an observer falling over it, something would be very wrong with the theory. If you're interested an of a mathematical bent, try googling for Painleve-Gullstrand coordinates, that's a coordinate system that proves that nothing odd happens at the event horizon.) It's a tiny fraction of a second later when they're dashed into a singularity that they notice something. Or perhaps a bit before when tidal forces rip them to bloodied spaghetti, of course.

Re:Does the program freeze at the event horizon? (1)

theshowmecanuck (703852) | more than 4 years ago | (#31134708)

I would have liked it to model the process of a black hole eating the earth if the large hadron collider actually did create a black hole.

Odd distortion ? (1)

SledgeFA (1742580) | more than 4 years ago | (#31133066)

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.

Re:Odd distortion ? (1)

abuelos84 (1340505) | more than 4 years ago | (#31135728)

The different "ways" are because:
FTS
The following movies show some example situations. You should download the files before playing.

The observer is rotating around the Schwarzschild black hole on the fixed radius rObs/rs = 5.0
(The first one)

The observer quasistatically approaches the black hole.
(the one that you are speaking about)

Free fall starting with zero velocity from rObs/rs = 5.0
(The one where TBH gets a nice shiny ring)

Now i have no idea what is to "quasistatically approach" something, but there's a clue if you feel adventurous today...

Peace & Piss

is this coincidence? (1)

thetanprofessor (1745054) | more than 4 years ago | (#31133312)

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

One (missing) part that's apparently not simulated (1)

Hurricane78 (562437) | more than 4 years ago | (#31133332)

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. ;)

Re:One (missing) part that's apparently not simula (2, Insightful)

kvezach (1199717) | more than 4 years ago | (#31133526)

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?

Re:One (missing) part that's apparently not simula (1)

MechaStreisand (585905) | more than 4 years ago | (#31133636)

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.

Re:One (missing) part that's apparently not simula (2, Interesting)

Tim C (15259) | more than 4 years ago | (#31133954)

Well that would happen at the event horizon, which by definition is the "edge" of the black hole anyway.

Re:One (missing) part that's apparently not simula (1)

maxwell demon (590494) | more than 4 years ago | (#31133728)

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:

  • Inside the matter shell, we have the Schwarzschild solution of the pure black hole (the Schwarzschild solution describes the spacetime of a static black hole)
  • Outside the matter shell, we have the Schwarzschild solution of the black hole plus the mass of the matter shell.

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.

That's one path to "hypercomputation". (1)

jeffb (2.718) (1189693) | more than 4 years ago | (#31134414)

This provides a way to perform a computation of infinite length within a finite interval [wikipedia.org] (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.

Acceleration disk missing (1)

Frans Faase (648933) | more than 4 years ago | (#31133504)

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.

Re:Acceleration disk missing (2, Informative)

Tim C (15259) | more than 4 years ago | (#31133774)

Nit-pick - the thing you're thinking of is called an accretion disk [wikipedia.org] , not an acceleration disk.

Re:Acceleration disk missing (0)

Anonymous Coward | more than 4 years ago | (#31133778)

Pssst... It's an "accretion" disc. Things are "accreting". They are, to be fair, accelerating too, but the feature from which it gets is name is the accretion.

Runs on 256mb video card..... (1)

ZosX (517789) | more than 4 years ago | (#31133546)

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.....

red shift (0)

Anonymous Coward | more than 4 years ago | (#31133994)

im wondering why i can't see any red-shift in the videos...

any ideas?

Looks like Giedi Prime from Dune (2, Interesting)

Jon Abbott (723) | more than 4 years ago | (#31135062)

That black hole in the video looks almost exactly like Giedi Prime [wikia.com] from Dune...

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