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Astrophysicists Build Realistic Virtual Universe

Soulskill posted about 5 months ago | from the go-big-or-go-home dept.

Space 129

sciencehabit writes "In the most detailed effort yet, astrophysicists and cosmologists have modeled the evolution of the universe right down to the formation of individual galaxies. The results of the mammoth computer simulation neatly match multiple astronomical observations, ranging from the distribution of galaxies in massive galaxy clusters to the amounts of neutral hydrogen gas in galaxies large and small (abstract). The findings once again neatly confirm cosmologists' standard theory of the basic ingredients of the universe and how it evolved—a result that may disappoint researchers hoping for new puzzles to solve."

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Wow, I just turned off ad-block (-1)

Anonymous Coward | about 5 months ago | (#46944377)

Who ever thought slashdot would turn into a spam infested sneaky Malware Distributor.

Cool! Where can I get one? (1, Funny)

Jane Q. Public (1010737) | about 5 months ago | (#46944385)

I wanted to get a dollhouse for the kiddies, but a universe is even better.

Re:Cool! Where can I get one? (2)

geekoid (135745) | about 5 months ago | (#46944479)

Well, you got to start with building the universe so you have some place to put your dollhouse, duh.

Re:Cool! Where can I get one? (1)

Kuroji (990107) | about 5 months ago | (#46944759)

What a coincidence, I've got an apple pie recipe that says the same thing.

Re:Cool! Where can I get one? (1)

rubycodez (864176) | about 5 months ago | (#46945107)

silly, you have to build the universe and then mom to get apple pie from the recipe

Re:Cool! Where can I get one? (0)

Anonymous Coward | about 5 months ago | (#46945351)

Here's a new Puzzle, who doubled clicked the original icon?

Re:Cool! Where can I get one? (0)

Anonymous Coward | about 5 months ago | (#46945949)

The Flying Spaghetti Monster clicked it with his noodly appendage, of course!

Build your own universe (0)

Anonymous Coward | about 5 months ago | (#46945363)

Here's one for you, and it's open source too: omegaverse.info [omegaverse.info]

Re:Cool! Where can I get one? (3, Informative)

wbr1 (2538558) | about 5 months ago | (#46944993)

Right here: http://universesandbox.com/ [universesandbox.com]

Re:Cool! Where can I get one? (0)

Anonymous Coward | about 5 months ago | (#46945655)

When will be able to 3D print a universe?

Re:Cool! Where can I get one? (1)

bill_mcgonigle (4333) | about 5 months ago | (#46945971)

You want a simulated universe? Just look around (but don't peek between 10^-26 and 10^-35 - ours cheats there).

Re:Cool! Where can I get one? (1)

Jane Q. Public (1010737) | about 5 months ago | (#46946917)

You remind me of the time some years back when I went to visit relatives and they had rented Existenz, Dark City, The Thirteenth Floor and The Matrix. I had no idea what they were about in advance, and I saw all 4 of them in one weekend.

I think I was a bit befuddled for a day or so after that.

Re:Cool! Where can I get one? (1)

Tablizer (95088) | about 5 months ago | (#46946135)

I wanted to get a dollhouse for the kiddies, but a universe is even better.

The black holes are where the Kardashian & J.Bieber dolls used to be.

So ... it covers these things? (1)

Payden K. Pringle (3483599) | about 5 months ago | (#46944395)

Where the extra matter went and how the universe expanded faster than the speed of light, temporarily?

Because something tells me TFA is missing that bit or exaggerating in their last line about puzzles.

Re:So ... it covers these things? (1)

flyneye (84093) | about 5 months ago | (#46944503)

I have problems with the reality of this universe, how much damn improvement could a computer sim offer?

Re:So ... it covers these things? (0)

Anonymous Coward | about 5 months ago | (#46945203)

You can be god and make people suffer.

Re:So ... it covers these things? (1)

flyneye (84093) | about 5 months ago | (#46947687)

Sounds like theyre trying to re-invent Evony...

Re:So ... it covers these things? (0)

Anonymous Coward | about 5 months ago | (#46946883)

I have problems with the reality of this universe, how much damn improvement could a computer sim offer?

-g

Re:So ... it covers these things? (0)

Anonymous Coward | about 5 months ago | (#46944695)

According to wikipedia, the radius of the (visible) universe is about 46billion lightyears. (so about 92billion ly dia)
The article uses a 106.5megaparsec per side cube. (about 347.3million lightyears).

The simulation appears to show that given "a random realization of this cosmology in periodic boxes with a side length of 75h^1Mpc106.5Mpc, starting from an initial ‘glass-like’ particle configuration composed of one thousand 182 particle tiles." The hydrodynamic simulation gives something that looks right.

Re:So ... it covers these things? (0)

Anonymous Coward | about 5 months ago | (#46944713)

What if there was an explosion so great that space itself expanded?
If so, you could go FTL without violating c in a local frame of reference.

Re:So ... it covers these things? (0)

Anonymous Coward | about 5 months ago | (#46947739)

Yeah, but then you'd have to shrink the universe to get back home!

Re:So ... it covers these things? (-1)

Anonymous Coward | about 5 months ago | (#46944773)

Boondoggle!

Re:So ... it covers these things? (2)

PolygamousRanchKid (1290638) | about 5 months ago | (#46945445)

TFA mentioned that they included Dark Matter in the model . . . which is quite bold, considering that we are still quite clueless as to what exactly that actually is . . . except that we need Dark Matter to keep our other equations from breaking . . .

Re:So ... it covers these things? (0)

Payden K. Pringle (3483599) | about 5 months ago | (#46945991)

Exactly. It almost feels like this was made just to make headlines. Don't get me wrong, progress is awesome, but at least be honest about it. For example, I'd consider honesty feeling the need to mention their considerations on Dark Matter and why/how they interpreted it in this model.

I don't feel like that's asking for too much personally.

Re:So ... it covers these things? (1)

Anonymous Coward | about 5 months ago | (#46946901)

Exactly. It almost feels like this was made just to make headlines.

Work like this is for a small segment of cosmology research and the paper is a natural progression from previous work. Nothing about it seems headline grabbing as far as the work and original paper.

For example, I'd consider honesty feeling the need to mention their considerations on Dark Matter and why/how they interpreted it in this model.

They used cold dark matter. How that is handled is covered in textbooks at the appropriate level at this point, so not much more description is needed other than specific implementation details and a reference or two.

Re:So ... it covers these things? (0)

Anonymous Coward | about 5 months ago | (#46946907)

Work like this is common for a small segment of cosmology research and the paper is a natural progression from previous work.

Managed to drop a whole word... can't blame that on the phone autocorrect.

Simalted? (0, Flamebait)

Anonymous Coward | about 5 months ago | (#46944447)

So, with a few words, the proposed theories, that are covering the existing KNOWN part of the universe, were used to simulate an universe, which resulted in exactly the same universe as expected.....Anyone else seeing what the problem is?

Re:Simalted? (0)

Anonymous Coward | about 5 months ago | (#46944619)

First "create a random realization of this cosmology in periodic boxes with a side length of 75h^ 1Mpc106.5Mpc, starting from an initial ‘glass-like’ particle configuration composed of one thousand 182 particle tiles."
Then run the simulation.

Re:Simalted? (2, Insightful)

Anonymous Coward | about 5 months ago | (#46944781)

Umm, it is how science works? You want to check that current theories are consistent with what you observe. If they had found a large disagreement, then they would know to try something else. If they find agreement, then they know they need to look closer from both theory and observation ends for any other sources of disagreement.

Re: Simalted? (2)

Scowler (667000) | about 5 months ago | (#46944857)

We are trying to understand those things we can observe. That doesn't preclude us from trying to observe more stuff.

Re: Simalted? (1)

weilawei (897823) | about 5 months ago | (#46946263)

Any predictive observations will necessarily be limited by the actual applicability of the model. A model may suggest directions to look for interesting phenomena, but it is NEVER confirmation of such. Simulations will only get you as far as your inputs. GIGO.

Keep adjusting until it looks right (-1)

Anonymous Coward | about 5 months ago | (#46944469)

Meanwhile, all you ever needed to do was read Genesis to understand what really happened.

Re:Keep adjusting until it looks right (3, Informative)

ColdGrits (204506) | about 5 months ago | (#46945675)

Meanwhile, all you ever needed to do was read Genesis to understand what really happened.

Meh, Genesis were never the same since Peter Gabriel left...

Re:Keep adjusting until it looks right (0)

Anonymous Coward | about 5 months ago | (#46947311)

Let's not worship Ibinov from lab 4's night shift, even if he did create our universe.
The guy still picks his nose.

Re:Keep adjusting until it looks right (1)

Tablizer (95088) | about 5 months ago | (#46946155)

A whole lotta begatting, good times!

Re:Keep adjusting until it looks right (1)

Petfish (1254220) | about 5 months ago | (#46946965)

I was wondering how they modeled the beard.

Trading routes (0)

Rinikusu (28164) | about 5 months ago | (#46944507)

I hope they have a pretty accurate trading model with a good economic base. Need to buy and sell across multiple systems to save up for that bad-ass ship.

Re:Trading routes (1)

Immerman (2627577) | about 5 months ago | (#46944869)

As a matter of fact they do. Their highly accurate model is based on the premise that "You, your ship, and everything in it die/decay/degrade beyond functionality before you get 10% of the way to the nearest star". If any sentient life happens to be orbitting that star then in a few thousand years when your remains arrive they may end up as part of a museum exhibit or Black-Ops coverup.

Without FTL the only things we could possibly trade in are knowledge and culture. And with FTL... well if Einstein was right then we'll probably be too busy altering our own history to worry much about trading with other stars.

Re:Trading routes (1)

Sique (173459) | about 5 months ago | (#46947059)

Even without FTL, it's possible to arrive at another stellar system within your life time, if you are able to constantly accelerate (and decelerate after half the distance). Thanks to time dilation, for you, about 5 years pass, until you arrive at the next stellar system (the exact number depends on your actual acceleration). The main problem: If you go back. on Earth, millions of years have passed on Earth until you arrive.

Re:Trading routes (1)

Sarius64 (880298) | about 5 months ago | (#46947257)

First you need political will. Sadly, that exists nowhere on this Earth.

Re:Trading routes (1)

CrimsonAvenger (580665) | about 5 months ago | (#46947925)

Well, yes and no.

Depending on how far "the next stellar system" is from start, and your acceleration, of course.

For 1G and 5 years, you'll go about 11 light years.

Beyond that distance, you'll add extra distance very quickly - 22 light years will take you 6.2 years. 100 light years will take 9 years.

And you can manage 11+ BILLION or so light years in only 45 years.

While this does theoretically allow traveel interstellar distances within a lifetime, for practical purposes (we don't really want to burn a significant fraction of a lifetime travelling - it would be nice to arrive young enough to enjoy the sights, at least), we're talking 10-50 lightyears as the upper limit we'll be travelling that way.

Of course, if we're actually really serious about becoming an interstellar species, we'll do most of the work at small fractions of c. 10% will be enough to get to nearby systems within a couple generations, allowing large colony ships to go there to settle. And further trips will start from those colony worlds to more distant places. Which should be sufficient to colonize the entire Milky Way within a couple million years....

Re:Trading routes (1)

Immerman (2627577) | about 5 months ago | (#46948363)

An excellent breakdown - just don't forget you also need fuel, though I suppose a ramscoop plus mass-energy converter would let you sustain accelerations once you got up to speed. The fuel for that initial acceleration and deceleration is still going to be pretty mind-boggling though.

I agree it's plausible for colonization or exploration purposes, but for trade? Trade needs to be cost-effective, and those shipping costs are going to be killer...

Re:Trading routes (1)

CrimsonAvenger (580665) | about 5 months ago | (#46948421)

I agree it's plausible for colonization or exploration purposes, but for trade? Trade needs to be cost-effective, and those shipping costs are going to be killer...

No, it's not worthwhile for trade, really. especially since no material good could possibly be worth shipping across interstellar distances. Trade, as such, would be trade in IDEAS, not things. And you can do that with a com laser.

As a completely off-topic aside: Is that dove EVER going to get laid? He's been chasing a dove hen around my backyard for over a week now....

Re:Trading routes (0)

Anonymous Coward | about 5 months ago | (#46948405)

Accelerating at 1 g for 5 years amounts to on average using the total power of humanity at the moment for those 5 years, assuming you are just accelerating a 100 kg person and no ship, and doing it perfectly efficiently with a method that does require the person to carry fuel. If they had to carry fuel, and propel themselves, that gets a lot more difficult.

Re:Trading routes (1)

CrimsonAvenger (580665) | about 5 months ago | (#46948455)

And your point is?

No, we can't do that right now. Noone has suggested that we can.

Does the fact we can't do it now mean it will be forever impossible? No. Lot of things we do do now would have been described as "impossible" 100 years ago.

Re:Trading routes (1)

Immerman (2627577) | about 5 months ago | (#46948319)

CrimsonAvenger did a great breakdown of time versus acceleration, so I'll just throw out a second factor: we can't actually pull off that kind of acceleration with any current (even speculative) fuel technology. Consider the size of the rockets used for orbital launches, just to accelerate a few thousand g at a few G for several minutes. Now increase that a few thousandfold to keep it up for a year. Except... it's even worse than that - far, far worse, because the fuel required for sustained acceleration increases geometrically (exponentially?) with the duration of acceleration - the fuel for the last minute only has to accelerate the rocket, but for the previous minute it has to also accelerate the fuel for the last minute, so it's slightly greater, and for the minute before that it needs to propel the fuel for the last *two* minutes, and so on and so forth - it snowballs *very* rapidly.

Now potentially a ramscoop + mass-energy converter might be able to maintain that acceleration after you get up to speed (I believe someone finally ran the numbers and showed that fusion wouldn't cut it - you couldn't produce enough energy to overcome the drag of your scoop - it's basically a massive parachute after all), but unless you're traveling through a pretty dense nebula that's probably going to mean you have to already be approaching lightspeed to pass through enough matter to sustain the propulsion, so you'll still have some mind-boggling initial fuel requirements.

All of which adds up to one thing: money. It might be justifiable to fund such a thing for exploration or colonization purposes, but for trade? What are you going to to trade in to justify the billions of dollars per pound shipping costs?

internal detection (4, Funny)

RichMan (8097) | about 5 months ago | (#46944511)

the big question is are entities in the simulation able to detect it is a simulation.

Re:internal detection (0)

Anonymous Coward | about 5 months ago | (#46944555)

the big question is are entities in the simulation able to detect it is a simulation.

Why stop at z=0? Run the simulation for a few more months of earth-computer time and see what happens. If the simulation's as accurate as it appears to be, it'll give as good a visualization of the endgame of our universe as we're likely to get for another few years.

(And if you see a giant bird-flipping finger at the end of the run, conclude that at least one hyperintelligent species of the color blue has figured it out, even if it took their civilization few billion years to adequately express their opinion :)

Re:internal detection (1)

geekoid (135745) | about 5 months ago | (#46944643)

We got to the end, and all we saw was:
4000000 GOTO 10

Re:internal detection (0)

Anonymous Coward | about 5 months ago | (#46944755)

haha. You are of course aware that they're not even simulating to within 10^10 of the level of detail required to detect if it's as simulation.

Re: internal detection (1)

Scowler (667000) | about 5 months ago | (#46944831)

Finite element analysis with discrete chunks basically the size of small galaxies. Pretty strange...

Re:internal detection (2)

Immerman (2627577) | about 5 months ago | (#46944913)

You are presuming, of course, an absence of sentient galactic clusters. Why must you be such a scale-ist?

Re:internal detection (0)

Anonymous Coward | about 5 months ago | (#46947297)

Have you even seen the local clusters on that skank?

Re:internal detection (1)

wonkey_monkey (2592601) | about 5 months ago | (#46947095)

You are of course aware of that whooshing sound.

Re:internal detection (1)

Tablizer (95088) | about 5 months ago | (#46946081)

are entities in the simulation able to detect it is a simulation...?

Yes, because they keep getting our spam.

Why are these simulations impressive? (0, Interesting)

Anonymous Coward | about 5 months ago | (#46944591)

I was always confused by these simulations. Isn't it a tautology that the simulations correctly reproduce the universe we would expect as they were generated from laws derived from observations of this universe? If the results that were reproduced differed then wouldn't the simulation be a poor simulation? It's not like these simulations are a true experiment. Always seemed a bit like CS masturbation to me.

Re:Why are these simulations impressive? (3, Interesting)

supertall (1163993) | about 5 months ago | (#46944707)

I thought the same thing at first. However, assuming that the simulation implements only the very fundamental building blocks of physics at it's core, it is interesting to see that they translate to match our observations on a macro scale. Given that, it's just a matter of what else we can glean from the simulation runs that we have yet to observe IRL. These new insights don't have to be taken as truth, but rather lead us to new observations.

Re:Why are these simulations impressive? (1)

Immerman (2627577) | about 5 months ago | (#46944931)

A more interesting thing, I think, would be to start with the universe we observe, and then run the simulation backwards to find out what initial conditions are necessary to create it. After all the equations are all fully reversible.

Re:Why are these simulations impressive? (2, Informative)

Anonymous Coward | about 5 months ago | (#46945441)

After all the equations are all fully reversible.

Most likely not in this case. I don't have access to the original article at my current location, but many other hydrodynamic cosmology models are not reversible because they result in an increase of entropy and a smoothing process that does not allow that to work backwards, which is kind of how reality is unless you are modelling every particle of gas clouds.

Re:Why are these simulations impressive? (0)

Anonymous Coward | about 5 months ago | (#46944819)

All of science consists of is laws derived from observations. The important point is to make sure those laws actually match observations. For the simplest examples, where you just plug numbers into a simple equation using a calculator (or slide rule, or order of magnitude estimate), you can eliminate bad theories before even proposing them. But for more complex stuff, where you need to look detailed or complex observations, you need to do more work to make sure that theory predict what is seen. A lot of the time when you hear news of a model or simulation, it is really just a partial differential equation solver, solving some basic equation of theory (sometimes with a term or two removed if thought insignificant) to make sure that observations match. If not, then you examine any assumptions you made about various effects not mattering, or re-examine the theory you started with. The current laws this were based on were not simply derived from making a simulation match what we see, but have been around before that and are continually tested by more and more detailed simulations.

What is Systems science? (1)

TapeCutter (624760) | about 5 months ago | (#46948307)

Always seemed a bit like CS masturbation to me.

Nice troll, here's your cookie.

Next time you go to the airport think about the following. The skyscrapers you pass, the bridges you cross, the car you ride in, the multi-level car park you park in, the plane you board were all designed with CS masturbation. The fact that over the last 30yrs (about half of my life time) it's become virtually impossible to get finance for any engineering projects without first performing CS masturbation is testament to it's power and utility. Numerical integration [wikipedia.org] is what these simulations are doing, and it's as valid as any other branch of mathematics for exploring the physical world. Simulation is how we find the results of solving the equations that comprise the so called "physical laws". Many (if not most) of the equations in those laws can only be solved through numerical integration since no analytical solution has been found. The laws themselves are just mathematical models that have been tested to a high level of confidence, they are no more or less "real" than the maths inside a well tested computer sim.

As an example there are no known analytical solutions to newtons laws of gravity when applied to a physical system such as the solar system (ie: the n-body problem). Since humans first started shooting rockets into space their trajectories have been planned using n-body simulations, such simulation are very accurate but not perfect, which is why we put small navigation rockets on space probes to correct it's course if it strays too far.

Isn't it a tautology that the simulations correctly reproduce the universe we would expect as they were generated from laws derived from observations of this universe?

No, simulations make predictions by solving the equations (laws) using numerical analysis. If the simulation does not match observations it could be a bug in the sim or a bug in the laws themselves (new knowledge), even better is when a sim predicts phenomena nobody has seen but is confirmed by later observations (new knowledge)

If the results that were reproduced differed then wouldn't the simulation be a poor simulation?

More often than not, yes. Things don't get interesting until the sim turns out to be correct when new observations are performed. For example the much maligned climate sims have discovered dozens of unknown phenomena that were later confirmed by observations. "polar amplification" and "stratospheric cooling" are two well documented examples.

It's not like these simulations are a true experiment.

As in they don't have a "control" and a "subject"? - Of course they don't, where do you get a "control" for a unique system such as the universe, the climate, the biosphere, the flow of molten metal in an engine block casting, a skyscraper that has yet to be built? Most practical problems in both nature and engineering have neither a control subject, or an analytical solution to the mathematical laws that (we think) govern them. In the modern world we attack those problems with a methodology known as systems science [wikipedia.org] , we do that because it's track record says it works.. WP claims the field got started in the 50's but my CS degree covered the subject in depth, as such I think it can be more accurately traced back to the very first computer built during WW2, the first "real world" application of that computer was to run a numerical analysis of artillery fire to create artillery tables for use in the field, prior to this the tables were calculated by hand by thousands of people with adding machines and a note book. I very much doubt the WW2 generals and admirals would have used them if they had not provided a tangible military advantage.

What changed in the 50's was that well funded corporations and academics got to play with the new technology, suddenly answering questions that would take a team of humans years to compute by hand were "doable" in hours, nowadays we can complete millions of man-years of error prone human work in minutes with a $150 video card. In fact it has now come to the point were it is impossible to design a modern cpu with using a modern cpu to do the number crunching for the circuit simulations. Picasso famously quipped "Computers can only provide answers", he died when I was at HS, long before most scientists realised that they also prompt interesting questions.

BTW: There's a paradox in current information theory when a simulation includes the machine that is running the simulation, it leads to an infinite recursion of simulations within simulations. The human mind contains a model of itself, how it overcomes that paradox is unknown.

simulating a phenomena does not validate the model (4, Interesting)

jclaer (306442) | about 5 months ago | (#46944617)

Choosing parameters that best simulate a model does not mean that model is correct.

Great news! (1)

Anonymous Coward | about 5 months ago | (#46944997)

Finally I'll be able to make an apple pie from scratch!

Re:Great news! (1)

stoploss (2842505) | about 5 months ago | (#46946909)

Finally I'll be able to make an apple pie from scratch!

Obscure Cosmos reference is obscure.

Re:Great news! (1)

Ginger Unicorn (952287) | about 5 months ago | (#46947597)

It's not obscure to this audience.

Re:Great news! (0)

Anonymous Coward | about 5 months ago | (#46947765)

We're not an "audience," we're a community!

Re:simulating a phenomena does not validate the mo (4, Informative)

DMUTPeregrine (612791) | about 5 months ago | (#46945211)

If there are no parameters for a model that allow the model to simulate reality, then the model must be incorrect.
If there are parameters for a model that allow the model to simulate reality, then the model may be correct, but may still be incorrect.

This work moves us from the first state to the second, at least when it comes to simulating rather large scale structure.

Re:simulating a phenomena does not validate the mo (1)

Tablizer (95088) | about 5 months ago | (#46946091)

Choosing parameters that best simulate a model does not mean that model is correct.

You mean my RC plane is not really governed by regression equations? Shit, there goes my Nobel!

Re:simulating a phenomena does not validate the mo (1)

DerekLyons (302214) | about 5 months ago | (#46946525)

When the parameters match observed conditions it does.

Re:simulating a phenomena does not validate the mo (1)

marcello_dl (667940) | about 5 months ago | (#46947111)

Science says you should be able to make predictions, so that the theory is valid. Matching observations in a model based on theories built to explain those same observations is circular reasoning.

This does not mean they are not on the right path, of course.

Re:simulating a phenomena does not validate the mo (1)

Sockatume (732728) | about 5 months ago | (#46947425)

The observations their model makes are different from the observations used to construct the model.

Re:simulating a phenomena does not validate the mo (0)

Anonymous Coward | about 5 months ago | (#46948337)

Matching observations in a model based on theories built to explain those same observations is circular reasoning.

Even if this were the case (its not, as it is a different set of observations that give things like the fraction of dark matter), an important step in developing a theory is to check that it actually matches observations you're trying to match. They didn't know a priori the results would work out as they did, as if it could have just been solved analytically they wouldn't be doing more and more detailed numeric solutions. It isn't circular reasoning, it is checking consistency with the possibility that it comes out inconsistent and fails.

Re:simulating a phenomena does not validate the mo (1)

Sique (173459) | about 5 months ago | (#46947077)

This is a valid statement for any theory, not just a theory expressed in a simulation. Just because the theory works for some chosen values, it doesn't mean the theory is correct. Basicly yours is a null-statement, it doesn't yield any relevant information.

Re:simulating a phenomena does not validate the mo (1)

Sockatume (732728) | about 5 months ago | (#46947421)

Their parameters aren't simply chosen, though: most of them come from a disparate range of experimental observations, and the remainder are constrained to reasonable values. Getting experiment out with experiment in, particularly when it's a range of different experiment types in each case, is strong evidence that a model is accurate.

"The free parameters of our model are set to physically plausible values and have been adjusted within the allowed range to roughly reproduce the relation between mean stellar mass and halo mass inferred from abundance matching analysis. The resulting parameter settings have been tested on smaller-scale simulations and high-resolution zoom-in simulations of individual Milky Way-like haloes."

Re:simulating a phenomena does not validate the mo (1)

Hypotensive (2836435) | about 5 months ago | (#46948141)

I think it would be quite fun to make a complete simulation of the events in Genesis. That'll make sure they were true!

Lies (0)

Anonymous Coward | about 5 months ago | (#46944639)

A whole universe? What assumptions did they make?

Re:Lies (0)

Anonymous Coward | about 5 months ago | (#46946621)

Got global warming/climate change/disruption?

Obligatory (1)

MrKaos (858439) | about 5 months ago | (#46944667)

42

Re:Obligatory (1)

Immerman (2627577) | about 5 months ago | (#46944959)

Actually that was a rounding error, the correct value is 947.2837289373726376152839

Re:Obligatory (1)

Tablizer (95088) | about 5 months ago | (#46946103)

God is MS-Excel? We're fucked

Re:Obligatory (1)

ComputersKai (3499237) | about 5 months ago | (#46945025)

“When you entered the door of my office, you entered my electronically synthesized Universe,” he explained. “If you had left by the door you would have been back in the real one. The artificial one works from here.”

really? (0)

Anonymous Coward | about 5 months ago | (#46944701)

So they know every thing about dark matter now, kudos.

Re:really? (3, Interesting)

rubycodez (864176) | about 5 months ago | (#46945143)

and apparently also know (without sharing) why the observed mass of the Higgs boson is so tiny even though the max energy times the fermion/boson sum should be huge. wow they have it all figured out...or they "cooked the books"

Funny (3, Insightful)

Anonymous Coward | about 5 months ago | (#46945089)

I love the part about "new questions to answer". As if "Where did the super dense mass the universe came from, come from, wouldn't be a good question to answer...

Confirmation bias. (1)

ourlovecanlastforeve (795111) | about 5 months ago | (#46946185)

Confirmation bias.

And this is the first step if... (0)

Anonymous Coward | about 5 months ago | (#46946367)

You wish to make an apple pie from scratch..

http://www.youtube.com/watch?v=9ssV79Qi7mM

Likelihood that we (1)

Swampash (1131503) | about 5 months ago | (#46946489)

are a feature of some other species' universe-simulation: high

They can model the Universe (0)

Anonymous Coward | about 5 months ago | (#46946491)

but not the climate.

"What I’m convinced of is that we don’t understand climate." - Freeman Dyson

So when... (1)

ignavus (213578) | about 5 months ago | (#46946509)

So when are they releasing it as a game?

while digging through the simulation... (1)

crispytwo (1144275) | about 5 months ago | (#46946689)

The simulation is uncanny! I noticed that there is only 1 planet with life on it!

Re:while digging through the simulation... (2)

squiggleslash (241428) | about 5 months ago | (#46948837)

And it's only six thousand years old! ;-)

Link to a non-paywalled abstract (1)

Anonymous Coward | about 5 months ago | (#46947075)

Hint to /. editors and submitters: when talking about physics and astronomy papers, it's really helpfu to remember the existence of the arxiv, where the actual professionals go to find the papers.

http://uk.arxiv.org/abs/1405.1418

(Also, hint to commenters on cosmology articles: saying things like "simulations are pointless because they're confirmation bias" and "but they don't understand dark matter LOLOLOLOLOL" just make you look woefully ill-educated in the area, even to the level that a cursory skim of Wikipedia would give.)

Re:Link to a non-paywalled abstract (1)

gl4ss (559668) | about 5 months ago | (#46947869)

you could have saved us a lot of time then by pointing out how it is not pointless, unless your point is "it gives me funding".

basically, how is this on any fundamental level any more useful than the galaxies screen saver is?

Re:Link to a non-paywalled abstract (0)

Anonymous Coward | about 5 months ago | (#46948367)

Whether or not something is pointless in the context of the research field, like a bunch of armchair cosmologists are trying to argue that simulation results are useless or amount to circular reasoning, is a whole different argument than whether the whole field is pointless to pursue.

Oblig. Douglas Adams (0)

Anonymous Coward | about 5 months ago | (#46947235)

Now all it needs is a white arrow with the label "you are here".

In other news (0)

Anonymous Coward | about 5 months ago | (#46947535)

It includes both normal matter and dark matter using 12 billion 3-D "pixels"

You mean 12billion Voxels.

If they had used an average desktop computer, the calculations would have taken more than 2,000 years to complete.

The problem with Java, right there ^^.

Title overstated (2)

argStyopa (232550) | about 5 months ago | (#46947957)

Probably a better one is "Simulation from the Big Bang results in output that looks like our universe at the galactic scale"

To suggest that this equals "Astrophysicists Build Realistic Virtual Universe" more than a touch hyperbolic.

Have they solved... (1)

Dcnjoe60 (682885) | about 5 months ago | (#46948047)

Have they solved the problem with quantum theory and the big bang being mutually exclusive (other than saying the laws of physics changed somehow)? If not, there is still a really big problem to solve.

Thanks! (0)

Anonymous Coward | about 5 months ago | (#46948261)

Thank you Nat' for this!

Outer Limits: create universe in lab (1)

peter303 (12292) | about 5 months ago | (#46948833)

But it runs thousands of times faster than ours. Eventually they evolve intellignece, discover our universe, and break into it.
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