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Astronomers Explode Virtual Supernova
DynaSoar writes "Scientists at the University of Chicago's Center for Astrophysical Thermonuclear Flashes have created a simulation of a white dwarf exploding into a type 1a supernova. Using 700 processors and 58,000 hours, they produced a three second movie showing the initial burst that is thought to be the source of much of the iron in the universe. Understanding these supernovas is also important to testing current cosmological theories regarding dark matter and dark energy, as their brightness is used as a measurement of distance, and discrepancies found in the brightness of very distant supernovas consistently seem to indicate a change in the speed of expansion of the universe over time."
http://flash.uchicago.edu/website/research/gallery /home.py
for all alternative OS users out there.
7000 processors and 58000 hours? SG-1 Did that in a single episode! On a TV special effects budget no less!
So, they started the simulation over six years ago?
Repton.
They say that only an experienced wizard can do the tengu shuffle.
Does anyone else see the "face" that is created during this explosion? I see closed eyes, a nose and even a mouth(all tongue in cheek) ROFLMAO... sorry poor joke..... would love to see this at full speed.
hee hee
I don't need no instructions to know how to rock!!!!
> created a simulation of a white dwarf exploding into a type 1a supernova. Using 700 processors and 58,000 hours,
They probably got Federal Funding for this by explaining it was "like sticking a giant firecracker up a giant frog"
You insensative clods! They killed my virtual friends and my virtual dog orbiting around that star on a virtual planet! Just because they are bits instead of molecules is no reason to demean them.
Table-ized A.I.
They literally blew a wod of cash
Table-ized A.I.
supernovas
Shouldn't that be supernovae?
Have you read my journal today?
I'm sorry, I had to check when their acronym spells CATFUC.
Help poke pirates in the eyepatch, arr.
Bob: But we'll never get funding with a three second image. This thing had to have caused something useful .. ... how about something specific like Kevin Federline?
Joe: Well, um
Bob: No, panders too much to popular culture.
Joe: That's too bad because my next thought was heavy metal music. Oh, how about some type of boring "metal" like iron ore. It's in some vitamins too which will interest the average consumer.
Bob: That'll do. We have to get the funding proposal out by noon.
Marvin the Martian 58000 hours before Bugs Bunny arrived...
There was supposed to be a simulated Ka-Boom. A simulated earth shattering Ka-Boom.
SciTechPulse. Geek News Netcast. Hot Polynesian Geek Chick Silulu.
looks like projectile diarrhea. i dont need 700 processors for that, just a 1.3 pound steak.
The 700 CPUs is not that much. What if they try the same simulation on 100000 CPUs?
= osstats
Btw: The Folding@home released a PS3 client and it has already overtaken all current platforms:
http://fah-web.stanford.edu/cgi-bin/main.py?qtype
...but why do these people persist in blowing so much time and effort and money on stuff like this when there are far more deserving and serious problems to be solved right here and now on good old earth. Hell, we can't even tame hydrogen --> helium let alone oxygen --> iron or whatever it is. Good, solid science for sure, but the priorities seem to be way, way wrong if you ask me.
Gah that article is awful. They link to pretty pictures and blurbs mostly and never really explain what these things are, why they are important or give you any real sense of scale. So since I like to beat on the drum of better communication of science, here is a little more detail to add to the good einhverfr's post.
The progenitors of SNIa are most likely white dwarfs composed of carbon nitrogen and oxygen, probably with a companion star from which they are stripping matter. They are very compact on the order of a few thousand kilometers at most, and really dense - more than the mass of the sun. They aren't hot enough to support fusion - they are supported by Pauli pressure; quantum mechanics doesn't allow two electrons in the same state at the same time so though gravity tries to compact these objects there is a Pauli pressure outward to balance it.
This can't go on forever in these progenitor systems however, and if the white dwarf strips enough matter of its companion to get to ~1.4 solar masses (the Chandrashekar limit) then Pauli pressure isn't strong enough to balance gravity and the star begins to collapse and when that happens pressure and temperature rises and somewhere a nuclear fusion flame ignites. Details about what happens near collapse, and where and how the flame ignites, and how many there are and how they progress are still debated. In this particular model they are considering only a single flame (so far) and its a "gravitationally confined detonation" (GCD - the name of this particular model).
Its a little difficult to get a sense of scale from those videos, though there are numbers in the bottom corner. The flame starts of near or just of center and becomes bubble/mushroom shaped through a Rayleigh-Taylor instability and breaks the stellar surface in under a second. Its less than another second before the ash and flame from the bubble collides at the opposite end of the star. This flame crashing into itself (see video 1) causes compression and a detonation.
Theres been a lot of debate as to whether its a deflagration or a detonation or whether it transitions from one to the other and how and when that happens and us poor graduate students just hope they don't go crazy over details of the progenitors during our qualifying examinations. This is notable because there appears to be a growing number of voices who are saying that a detonation is necessary. These events are so standard because they all become SNIa if they get near 1.4 solar masses. There is a fair bit of diversity (and some just crazy objects) and most of that probably arises from details during the explosion which is why modeling them is partly why the models are so important.
There is still a lot of modeling left to do. This flame is producing a lot of heavy elements (there is O, S, Ca, Mg and Si in the early spectra - the silicon feature is around 6150 angstrom in the rest frame and is the marker of a Ia at low to moderate redshifts). As the outer layers expand and become more transparent you see more of the material produced during the explosion and a lot of this is Nickel (Ni-56) which decays to cobalt and powers the light curve so you get this typically 2 week rise and then a slow fall off. Later times most of the Ni has become cobalt which is decaying to iron and you see these elements in the spectrum. The energies we are talking about here are about 10^45 Joules. A H bomb by contrast is 10^15 Joules so 30 order of magnitude. Unless you can picture 10^30 H bombs going off its hard to get a feeling for this number but thats generally the case with numbers in cosmology.
There are a lot of empirical relations you see from the lightcurve, which are exploited to standardize them (for instance the brighter the supernova, the slower its rate of decline, and there are relations for the colour...) and if a model can replicate them and match the observed lightcurves and spectra then this is a very impressive accomplishment. I skim
Reality must take precedence over public relations, for nature cannot be fooled.
There's a much better, and more recent article on this simulation hosted at www.nasa.gov - but the site is unbelievably slow to load as of late. You can see the nasa.gov article mirrored at http://douginadress.com/news/spaceexploration/berk eley_labs_supernova_data_crunching.html
Ace
As I have stated before here in other postings, I believe that simulation is the unrecognized and discounted factor that accounts for the Fermi Paradox, the fudge factor in the Drake equation that explains why we don't have aliens walking among us today. We are getting quite good at simulating reality ourselves, and there is no reason why extraterrestrial intelligences wouldn't do the exact same thing.
At some point soon, the synthesis of our scientific knowledge will allow us to assume, with considerable certainty, that aliens with similar biology and physics exist, probably in other solar systems in this galaxy and almost certainly in other galaxies.
They have of course reached the same conclusions and that is why they aren't trying to contact us.
We don't have to go exploring to find them. It's cheaper to just imagine them and simulate them. The real problem is what do we do if we decide to believe this?
it's a blue bright blue Saturday hey hey
In fact, the word is built out of two Latin adjectives, literally it means an "abovenew". Invented words follow this rule, hence the plural of octopus is octopuses, of satellite is satellites, and of millennium is millenniums. The plural of "vertebra" is "vertebrae" because it is an actual Latin word, not an invented modern one.
Incidentally, while pursuing this very pedantic note, "satellites" is correct plural but the singular of the original word is "satelles". And the original word is pronounced sat-ell-it-ees. We are a long way from Latin.
Pining for the fjords
"You seen one nova, you seen 'em all."
... as if a million bits cried out at once and then were silenced!
A beouwulf cluster of these!!!
By the pricking of my thumbs, Something wicked this way comes: Open, locks, whoever knocks!
Looks like the 10 year visionary project paid off right at the end. Long term financing was required along with faith in the project's people.
Slashdot: Where nerds gather to pool their ignorance
I found that passage confusing, too. I did some googling and found another (quite readable) article that suggests it is the latter:
FTFB: the initial burst that is thought to be the source of much of the iron in the universe
I always thought that iron was produced without the nova and that it was elements that are heavier than iron that were created by the blast. Am I wrong on this?
Dedicated Cthulhu Cultist since 4523 BC.
It was a pretty darned good nova, but I wouldn't go so far as to say it was super.
Now the '69 Yenko Nova (the ones with big blocks, not the LT-1 350's for 1970). That was a super Nova!
or does anybody else have a sudden craving for pop corn?
Parent is a troll and uses the same site over and over again
58,000 hrs for 3 secs, or 69,600,000 computational secs per sec real time. They'll need to do some performance tuning before they go for 1 minute simulations. ;)
What's fascinating to me is the behavior of the explosion front. At first it seems counterintuitive for it to 'burrow' towards the surface and burst asymetrically. But when you stop and think about it, that is the behavior you should expect - the expansion is the direction of least resistance, into regions of lower pressure.
What a waste of copmuter time and energy.
Didn't they have a good 3d application.
How about povray or 3d max joking..
but only 3 sec thats almost nothing...
1...2...3 and here is our electricity bill and hardware bill ping $1xx.xxx.xxx.-
I know you're out there. I can feel you now. I know that you're afraid. You're afraid of us. You're afraid of change.
Um, hi. Astronomer here (not that it matters).
The word nova in the astronomical context comes from Tycho Brahe, a Danish astronomer who was writing in Latin at the time. The plural is novae, not novas. Although supernova is an English construction, the etymology is derived more directly from this Latin word than other modern inventions. Although both plural forms are strictly correct due to the artificial construction, supernovae is used predominantly in our field.
It's a trap!!@#!#!@!@#!#@!
Well, you are correct, to a point...
We need to keep the scientific method in mind anytime we read a study. Far too many people are willing to take a study as an absolute truth instead of a new way of seeing an incident. This coupled with the fact that too many people already have a problem with the concept of a law and a theory makes talking about science in a meaningful way fairly hard.
So yes, there is tons to be discovered even in our own backyard but at the same time theories and predictions can be made with some degree on without knowing everything there is to know. For example, we didn't need microscopes and such to know that a muscle's contractions is what makes a body move but on the other hand we needed better powers of observation to understand the virus. I'm sure our theories on astronomical events of this nature will be a topic of debate for a long time to come but it doesn't hurt to consider the possibilities. Be thankful for it too; it's the way of progress.
Dedicated Cthulhu Cultist since 4523 BC.
So astronomers can do what they like, but I for one will grit my teeth. I don't have any objection to neologism whatsoever, but trying to make it look like Latin is just pomposity.
Pining for the fjords
By the time the simulation finished the current processors are what, about 5 times faster?
Did they upgrade the processors as it ran or just let it run as-is? Seems like it could have been completed faster if they continually upgraded the processors.
If you need any help picturing what they're studying, this professor's here to tell you why a supernova would be totally awesome!
I accept your logic. But you fall short of describing the complete scientific method. If you make assumptions, and then make additional observations that tend to disconfirm your assumptions, then there are times when your discoveries should cause you to re-examine your initial assumptions. We've launched all sorts of probes and telescopes since we came up with our astronomical theories, and although you can make a case that the data does match the theory, attempts to prove otherwise have fallen out of favor. So, by adopting the assumptions as "mainstream" and then moving on as business-as-usual, we've damaged the objectivity of science. People are more inclined to believe the assumptions than the disconfirmatory data returned from the probes and telescopes. That is an important part of the story of astronomy today.
... coming to the awareness that, wait a minute, should I be believing what these people are telling me? ...
One of the most curious things that nobody seems to be talking about is how astrophysicists appear to have garnered for themselves the right within the scientific community to dictate science back to the domains from which astrophysics is based upon. Not only is astrophysics a meta-science, but if you judge astrophysicists on how confident they are in their *interpretations* of their observations, they appear to believe that it is the *foundation* of science. This is problematic because it frequently causes us to favor their interpretation over other peoples' laboratory work and even mankind's common sense (dark matter and dark energy, for instance). This failure of context has the potential to bleed into all of our textbooks like a virus. Many people, like myself, believe that it has already happened. Even if you don't, no rational scientist can hold up this system and declare that it is impervious to major potential problems.
This thread's originator is an example of somebody awakening from a sleep
If this person digs a little bit further into the issues, he may also discover that we've discovered many very unusual morphologies for supernova remnants (the classic being 1987A) that appear to violate our early assumptions regarding stellar evolution. So, how can you possibly consider a supernova to be a "standard candle" if all we have to show for our understanding of them is retroactive simulations and a theory that has underperformed in its predictive capabilities? Many of the supernova remnants are hourglass morphologies. One wonders exactly what perspective the observer must be in in order for the "standard candle" luminosity during the explosion to apply?!%$ It's patently absurd, if you ask me.
For the mainstreamers out there, this is how interest within against-the-mainstream ideas begin. People stop *listening* and start *thinking* about what they're being told. They remember that they have a brain that can perform simple logic, even when complicated issues are involved. Oftentimes, an expert or enthusiast will then chime in with some complex evidence regarding the CMB or some textbook astronomy facts regarding the mainstream opinion. But their words are fashioned solely to cause the person asking the questions to stop *thinking* and conform back to the mainstream. They rarely stop and wonder, "Wait, maybe I swallowed bullshit too!"
It's all quite a spectacle, if you ask me. It's very possible that either (a) our children will laugh at us (best cas
"A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
wudnt watch this with shitty macromedia flash or whatever it is. those idiots are trying to turn the internet into a tv.
>>Now, I'll proceed to tie myself to the stake and pour gasoline upon myself. It's become routine now. I know what to do.
LOL. I noticed you mentioned in some previous posts that if a person wants to argue for EU theory you will get better with time and practice as you give arguments.
Ill have to admit your posts are really clear and concise and have improved. I would have to quit my day job to make posts as long and as neat as yours.
I notice that when people mod you troll and argue against you they dont really provide much substance. They will say "EU theory has been proven wrong get over it" or something to that effect but NEVER provide any examples or cite any references. The most I saw recently was some guy posted a URL to some chart about background radiation and that was it. woop dee doo.
Anyways keep at it!
PS: I went to the bad astronomy forum and didnt really care all that much for it. maybe some interesting thing here and there but a lot of noise.
It's a constant process of doubting your own arguments though. In this particular case, I screwed up a little bit because 1987A is categorized as a Type II supernova, which is not used as a standard candle. Type 1a supernovae are used for standard candles.
One of the difficult things in thinking about the arguments on both sides is merely keeping track of all of the categorization that has been created to accomodate the observations to the Big Bang and stellar evolution theories. Traditional theories tend to break the universe into parts and conquer them one at a time because a gravity-centric universe would lead to a bunch of disconnected processes. EU Theory, on the other hand, attempts to understand unifying principles within the universe because it proposes that the system is for the most part interconnected by filamentary plasma. I try very hard to get everything right by fact-checking, but sometimes things slip through. Better here, though, than on a stage in front of a thousand people (which is where I hope to one day end up).
In the end, you have to spend just as much time learning about the traditional theories as you do EU Theory. But the more you do that, the more it pays off. It's easy to argue *for* EU Theory. But it's much harder to argue *against* BB Theory and stellar evolution with people who are familiar with the latest research.
It's educational to at least take a quick peek at the Bad Astronomy Forums (although I'm with you in that I can't take too much of it). It raises your awareness that there are very complicated debates happening on the subject. Most importantly, it also demonstrates the attitude amongst the mainstream astrophysicists that they do not believe it is their burden to investigate all cosmologies. The public is not really aware that this is happening. Many people consider BB Theory to be too theological for them. But they accept that since it's discussed the most, then it must have the most evidence. But it's the choice of the mainstream astrophysicists to generate that evidence. They can also generate confirmatory evidence for plasma-based cosmologies too. They just don't want to. This is one of the things that the public needs to learn. It could have a dramatic impact upon the global warming debate. When the solar system appears to be inexplicably warming, there is a burden to investigate all possible explanations. For the astrophysicists to allow their preferences and prejudices to get into the way of solving a problem that threatens the existence of all people is on some level both selfish and irrational.
By the way, although people still like to point to the cosmic microwave background data every chance they get, astrophysicists are still having difficulty proving that the light originates from the edges of the universe. If objects between us and the light do not cast shadows, then the light would have a local origin. I've seen it speculated that the microwave radiation could in fact be the result of filamentary plasma moving currents through space. It would be somewhat ironic if the astrophysicists have accidentally stumbled upon a mechanism for proving the pervasiveness of electrical plasma in space when in fact they were trying to prove an afterglow from an explosion.
"A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
I wanted to add one more thing to my previous response.
What's happening right now with astrophysics is extraordinary. It's never been the case to my knowledge that modern man has been so wrong about something and simultaneously so confident in his wrong beliefs. The implications can potentially be catastrophic in the long-term. But there is a little-mentioned business side to this story. The EU Theorists have done a great job of laying down the groundwork for some possibly lucrative financial ventures. I mention this because if this is something that you have an interest in, it might pain you ten years from now to see others making a bunch of money off of it when in fact you had a head start on those people who will be doing so.
The theory could act as an excellent foundation or starting point for a movie script or book. My personal goal is somewhat different though: I want to create a small crew, a traveling road show, based upon a Burning Man style geodesic dome camp that can be disassembled and packed into a freight truck. The goal is to make the science entertaining. This is where electricity comes in. Electricity by itself has lots of excitement potential. The show I want to put on will be part demonstration, part live performance (perhaps with ambient DJ's, drummers and fire dancers) and a big part educational. I want to convert all of the concepts of EU Theory into CGI graphics. I want people with no math skills to be able to compare the two sets of simulations (mainstream vs EU) so that they can formulate an opinion on their own. My dome will have numerous projectors, plasma globes, jacob's ladders, tesla coils, perhaps a terrella and exhibitions involving plasma phenomenon. There will be simulated lightning strikes in audio and with special effects, and fire art worked into the show. But the main purpose will be to present the evidence for EU Theory in the form of CGI graphics that can be selected in real-time. I want to be able to move through the graphics at my own pace as I explain the concepts. This will be a place where EU concepts can be heard by the public in the absence of dissenting mainstream astrophysicists (as happens on this forum). The crew for this show would probably have to live on a bus and would travel around the world, delivering the EU message throughout primarily North America and Europe. It's an unusual concept that I'm only on the early stages of planning for. But if that sort of thing interests you, or if you know anybody with CGI experience, let me know. I'll probably start building the dome within another two years for Burning Man. It will start as a Burning Man camp for 2-3 years, and then once I get enough equipment going, I will transition it to a road show and start making money off of it. I hope to build my own CGI cluster within 1-2 years. If I have to learn CGI myself, I'll do it. But I'm always searching out for people to join me. I already have a close friend who knows how to handle professional audio and video equipment. Just thought I'd mention it. It's obviously a long-term goal, but it's something that I am committed to seeing through. That's how I will fit into this whole picture. I'm not a theorist. I'm just the middle man for the conveyance of information to the public.
"A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
Sounds like an interesting plan. I was thinking that EU proponents should at least do speeches at colleges and the like. Try to get the word out there and have an effective presentation. I think maybe 1.5 hour or so would do the trick.
Are any of the guys affiliated with thunderbolts.info doing anything like that? I know theres problems with the peer review thing and submitting papers but I think presentations at educational institutions would be the best route.
A traveling roadshow sounds neat but risky. Its like going to some major movie studio and telling them you have this idea for a movie that you want to direct but never done anything like it before. Could flop big time or not, you never know.
Is there anyway to contact you without having to resort to posting email address?
You can reach me directly at pln2bz@vireo.net. I don't mind posting my email address. To be honest, nobody on this forum really cares what I think. And I don't care that they know what I'm doing.
There is nobody currently focusing on the educational system, believe it or not -- not since Hannes Alfven at least, who died more than a decade ago. Hannes Alfven was smart in that he left many descendants of his inquisitive philosophy. You can run into these guys all over the place on the web. The best thing, believe it or not, is that they don't all agree with one another like the mainstream astrophysicists do these days.
The main issue with your idea is that you're underestimating the reaction that you would receive from the astrophysics staff at any university you attended with an astrophysics department. They all unanimously consider EU Theory to be pseudo-scientific because they have all been taught, ironically enough, Alfven's *early* works on frozen-in-place magnetic fields. Few of them are aware that Alfven actually tried to convince everybody during his Nobel Prize acceptance speech for magnetohydrodynamics that currents must be causing the magnetic fields. I've noticed this once firsthand here on these forums. One of the few astrophysicists I've actually run into on these forums tried to correct me on this point and I had to go back and find the specific quotes. All of this doesn't really mean that your idea is bad. It just means that you need to be prepared for resistance, and when it happens, you should thrive off of it. You need to have some plan for taking advantage of the resistance within the media. Use the "bad" publicity that you will inevitably get and somehow turn it into a good thing that gets EU theories and proponents more exposure. This can be tricky because the 30-second sound byte works against you: it's currently far more believable to an uninformed audience to claim that electricity does not flow through space than it is to assert that dark matter doesn't exist. So long as dark matter is not really specified in any detail, it retains an element of possibility. The second you start getting into specifics about electricity flowing over diffuse interstellar clouds of matter and into the Sun, it's easy for people to knock you down as being absurd even though you may know much more about the issue than others.
For these reasons, I suspect that at least initially, targeted anonymously posted materials would be more effective than live talks at universities. I've spent a lot of time contemplating this and I even got to a point where I was planning out fliers for creation and distribution. The Thunderbolts crew, I'm sure, would enjoy being a part of this. If you decided to travel around the country, for instance, visiting the premier astrophysical institutions and posting bills or leaving copies of some type of EU materials so that they could be found by astrophysics students, this would certainly have a long-term impact and the EU people would probably offer their help. Wallace Thornhill, the guy who kind of took over where Alfven left off, says in his bio that he had to leave the educational system because he became so discouraged by the atmosphere. As a side note, you should be aware that the EU guys are on the verge of creating a public user forum, where enthusiasts can talk to one another about such things.
The problem is that, although this would be *very* fun, there is no money in this. You would have to somehow have a reserve to draw upon and a never-ending will to just do good in the absence of profit.
My idea of the traveling road show isn't actually as risky as it sounds when you consider that I'm starting out at Burning Man, a non-commercial venue that has a high percentage of my real target audience. That event is attended by huge numbers of tech-savvy silicon valley entrepreneurs and CEO's, believe it or not. There is an element of certainty that something positive (in terms of connections) would develop from that experience. Over th
"A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.