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Giant Sheets Of Dark Matter Detected

ScuttleMonkey posted more than 6 years ago | from the universal-coffee-filter dept.

Space 231

Wandering Wombat writes "The largest structures in the universe have been, if not directly found, then at least detected and pounced upon by scientists. 'The most colossal structures in the universe have been detected by astronomers who tuned into how the structures subtly bend galactic light. The newfound filaments and sheets of dark matter form gigantic features stretching across more than 270 million light-years of space — three times larger than any other known structure and 2,000 times the size of our own galaxy. Because the dark matter, by definition, is invisible to telescopes, the only way to detect it on such grand scales is by surveying huge numbers of distant galaxies and working out how their images, as seen from telescopes, are being weakly tweaked and distorted by any dark matter structures in intervening space.' By figuring how to spot the gigantic masses of dark matter, hopefully we can get a better understanding of it and find smaller and smaller structures."

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So ... (4, Funny)

supun (613105) | more than 6 years ago | (#22575764)

is it 1x4x9?

Re:So ... (1)

ROMRIX (912502) | more than 6 years ago | (#22576100)

Just guessing here but if it conforms to standard building code it would be 4x8x1/2... not sure of the scale though.

Re:So ... (1)

An ominous Cow art (320322) | more than 6 years ago | (#22576170)

So naive to believe that the ratios end there...

(probably misquoted from 2001)

Re:So ... (3, Funny)

ObsessiveMathsFreak (773371) | more than 6 years ago | (#22576258)

It's 1x4x9 + 6, obviously!

Re:So ... (4, Funny)

AKAImBatman (238306) | more than 6 years ago | (#22576664)

Actually, it's just the walls of the Universe. The simulation uses a 32 bit number to handle the coordinate system, so it needed to fit within 2^32 light years. I told God he should have used a 64-bit processor, but he complained that they were too expensive back in 1970. I bet he's kicking himself now, eh?

Re:So ... (1)

elcid73 (599126) | more than 6 years ago | (#22576958)

Beautiful. I'm going through Clarke's books again and that's the first thing I thought of as well.

Frosty Piss (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#22575774)

Giant streams of Frosty Piss have been detected. Astronomers claim that some of them form tall, steaming mugs of the substance. More details as it comes in!
 

dark matter (2)

hellfish006 (1000936) | more than 6 years ago | (#22575776)

now I can finally get some fuel for my ship

Re:dark matter (0)

Anonymous Coward | more than 6 years ago | (#22576060)

now I can finally get some fuel for my ship
No, ordinary dark matter doesn't work according to the superdupersymmetric string theory. You need neutron encrusted steamming hot dark matter for that.

feels like dark grits (0)

Anonymous Coward | more than 6 years ago | (#22575788)

you know the rest

Heh (4, Funny)

TheLink (130905) | more than 6 years ago | (#22575814)

Given that > 90% of the stuff out there is not even made of the same stuff like us - in the great scheme of things we are:
a) Interesting
b) Not interesting
c) Both (don't you love quantum superpositions ;) )

Re:Heh (2, Insightful)

KublaiKhan (522918) | more than 6 years ago | (#22575882)

Interesting or noninteresting to -whom- exactly?

It's really probably just a point of view issue. After all, should there be 'dark matter organisms' of some kind, they'd be most likely supremely uninterested in the likes of us for anything other than curiosity value. However, we're rather interesting to us, being as we -are- us and we tend to be somewhat self-interested.

Re:Heh (1)

moderatorrater (1095745) | more than 6 years ago | (#22576070)

should there be 'dark matter organisms' of some kind, they'd be most likely supremely uninterested in the likes of us
I disagree. We'd be interested in dark matter organisms for more than just curiosity (although that's what it would look like at first). Establishing trade, etc would all be of supreme interest to us; why wouldn't it be for them?

Re:Heh (1)

KublaiKhan (522918) | more than 6 years ago | (#22576164)

What would we trade, exactly? Information's all I can think of (provided we had a way to communicate, anyway)--after all, it's not as though we can interact in such a way as to trade any sort of material goods, is there?

Though I suppose we could outsource telemarketing....

Re:Heh (1)

moderatorrater (1095745) | more than 6 years ago | (#22576276)

Unless I'm mistaken (and I often am), dark matter interacts with itself equally well as it interacts with regular matter, so there's a good chance we'd be able to use what they have and vice versa.

Besides, even if we were just able to trade information that would be a worthwhile endeavor.

Re:Heh (1)

KublaiKhan (522918) | more than 6 years ago | (#22576322)

What'm I going to do with something at that scale, though?

Re:Heh (1)

Wandering Wombat (531833) | more than 6 years ago | (#22576474)

I don't know, but it would look GREAT in my crapper... I mean, crappiere.

Re:Heh (1)

brianwgray (937533) | more than 6 years ago | (#22577154)

And here I was under the impression that when you come in contact with the dark matter object you're trading it and you annihilate. Maybe I just haven't had enough experience with dark matter...

Re:Heh (0)

Anonymous Coward | more than 6 years ago | (#22576206)

trade in _what_ exactly? it's not likely, given the nature of interactions between matters standard and dark, that we need and value similar things

Re:Heh (1)

Mr_Freedownload (1192043) | more than 6 years ago | (#22576896)

What have we got to trade? we can barely support our own planet.
Until the term "third world" no longer exists we have nothing to trade.

Re:Heh (1)

Enlightenment (1073994) | more than 6 years ago | (#22577004)

Okay, so Stephen Baxter came up with this idea already. Read _Vacuum Diagrams_. His idea is basically that since we can interact gravitationally, that will likely form the basis for contact.

Re:Heh (1)

thesandtiger (819476) | more than 6 years ago | (#22577038)

That's a pretty silly question, and hardly insightful. We are, as a species, interested in all kinds of things that aren't very similar to us. Why wouldn't there be interest in something that is completely alien - not even made of the same kinds of matter as we! - the study of which might yield all kinds of interesting bits of knowledge?

We have people who spend lifetimes studying the works of mediocre poets from 500 years ago, are you seriously suggesting that there wouldn't be an interest in dark matter life?

While it's certainly not possible to say with any certainty that dark matter life would be interested in us, given that the all "intelligent" species we know of so far show some evidence of curiosity, it's probably not unreasonable to imagine that alien life - even non-baryonic life - could be curious about us.

Re: Interesting / Not interesting / Both (3, Funny)

gnick (1211984) | more than 6 years ago | (#22576044)

I typically consider myself Interesting, but I never really know for sure until mod points are assigned. Occasionally, I'm Funny, Insightful, Informative, or Overrated... Sometimes all at the same time!

Re:Heh (1)

Sethus (609631) | more than 6 years ago | (#22576428)

Well... I wouldn't say we're interesting. And certainly *Not* interesting. So I guess my answer would be that we are the complete absence of interestingness. The line between ying and yang.

Re:Heh (1)

Wandering Wombat (531833) | more than 6 years ago | (#22576908)

We're a condom?

Re:Heh (3, Funny)

Red Flayer (890720) | more than 6 years ago | (#22576782)

d) harmless
e) we won't know until "they" open the box
f) mostly harmless

King size? (0, Offtopic)

KublaiKhan (522918) | more than 6 years ago | (#22575820)

So now that they've spotted the large ones, perhaps they can get the queens and twins as well. Dark Matter would probably be a great seller amongst the goth/emo crowd--after all, once you've painted your walls black and gotten black carpets, it wouldn't do to have "My Little Pony" sheets, would it?

Re:King size? (1)

sm62704 (957197) | more than 6 years ago | (#22576396)

I found a picture of the dark matter [uncyclopedia.org] ! Or... well hell it might be a black hole. [uncyclopedia.org] Oh wait...

Let me be the first to say (3, Funny)

QuantumFTL (197300) | more than 6 years ago | (#22575830)

Take that MOND [wikipedia.org] !

Soon all your adherents will have to move to studying a crazy theory that can't disproven, like String Theory!

What if.... (2, Interesting)

EntropyXP (956792) | more than 6 years ago | (#22575834)

What if it isn't dark matter at all? But the Universe actually bending? I read a description of the universe expanding like a snail building its shell... it doesn't expand in all directions infinitely but instead curls on itself like a snail shell.

Re:What if.... (4, Informative)

exp(pi*sqrt(163)) (613870) | more than 6 years ago | (#22576768)

> What if it isn't dark matter at all? But the Universe actually bending?

But that's exactly how it's being treated by physicists. Here [wikipedia.org] are the very equations that physicists use to described the bending of spacetime by matter, dark or not.

Re:What if.... (1)

kalirion (728907) | more than 6 years ago | (#22577152)

Or it could just be gravity seeping in from another dimension/brain/membrane/whatever.

Re:What if.... (0)

ILuvRamen (1026668) | more than 6 years ago | (#22577190)

I'll shoot an even more obvious one at you. What if instead of a huuuuuuuge cloud of magical invisible matter bending the light on the way here, there's a single brown dwarf a billion times closer bending the light and we can't see it. And if you're going to say that wouldn't be enough mass, if two of them are just out of the line of sight and both bend it, it would have a similar effect as a huuuge cloud of matter further away.

I hear Hot Topic are already interested (1)

Channard (693317) | more than 6 years ago | (#22575836)

Sheets of Dark Matter? I guess that's this season's goth clothing range sorted out then. Just when you thought it couldn't get any blacker than SuperBlack [transstudio.com]

Re:I hear Hot Topic are already interested (0)

techpawn (969834) | more than 6 years ago | (#22576074)

Just when you thought it couldn't get any blacker
As soon as they find something that's the blackness of an emokid soul we're all set...

The Universe's Cytoskeleton? (0)

Anonymous Coward | more than 6 years ago | (#22575844)

What if dark matter is the supporting structure of the universe, kind of like a cell's cytoskeleton?

Three times larger? (3, Interesting)

amstrad (60839) | more than 6 years ago | (#22575892)

The Virgo Supercluster [wikipedia.org] is 200 million light years in diameter. And I'm sure there are large superclusters known.

Re:Three times larger? (4, Interesting)

Wandering Wombat (531833) | more than 6 years ago | (#22575966)

That's not really "One structure", though... it's a lot of small structures close together. A big pile of sand isn't the same as a big sheet of glass.

Re:Three times larger? (5, Insightful)

TheEmptySet (1060334) | more than 6 years ago | (#22576102)

It's a good philosophical question though. When is a collection of things (say atoms, bricks and mortar, etc.) a thing and when is it just lots of things? Deep down atoms don't come anywhere near touching each other to make molecules and larger structures. I myself am just a collection of tiny dots floating in space a long way from each other.

Re:Three times larger? (1)

Nullav (1053766) | more than 6 years ago | (#22576454)

How about...close enough to stick? Sure, everything has a great deal of empty space, but my hand hasn't disintegrated yet. (Though now I'm wondering if this means a huge block of ice counts as a single structure while liquid water doesn't.)

Re:Three times larger? (3, Interesting)

Wandering Wombat (531833) | more than 6 years ago | (#22576610)

Well, atoms interact strongly with eachother, to the point that homogenous iron can withstand forces in excess of a thousand times it's own weight. A school of fish, which is more accurately comparable to that cluster, is not one BIG fish... it's a bunch of small fish all hanging out in the same area, and although they are close together, it would be quite easy, compared to the size and mass and force of the group, for them to be pulled apart.

Re:Three times larger? (2, Funny)

Anonymous Coward | more than 6 years ago | (#22576118)

Imagine a Beowulf...

Re:Three times larger? (1)

Ardipithecus (985280) | more than 6 years ago | (#22577212)

"The Great Wall, sometimes more specifically referred to as the CfA2 Great Wall, is the second largest known super-structure in the Universe (the largest being the Sloan Great Wall). It is a filament of galaxies approximately 200 million light-years away and has dimensions which measure over 500 million light-years long, 300 million light-years wide and 15 million light-years thick." http://en.wikipedia.org/wiki/Great_Wall_(astronomy) [wikipedia.org]

The Sloan Great Wall is not a real structure, rather an observational artifact, so the CfA2 takes it. No disrespect to the dark matter, or as they like to say, "the real universe"

http://en.wikipedia.org/wiki/Large-scale_structure_of_the_cosmos [wikipedia.org]

I love it... except I don't (-1, Flamebait)

Bryansix (761547) | more than 6 years ago | (#22575898)

I love it when all these theories get presented as fact. It gives me warm fuzzies insid... who am I kidding, it makes me want to puke.

Re:I love it... except I don't (1)

MightyYar (622222) | more than 6 years ago | (#22576026)

I don't mind no usage of the word "theory" on Slashdot or in the scientific press because the audience is likely to be familiar with the topic and know that it is not a "fact".

But you are right, the Discovery Channel is mainstream and should definitely point out that the theory is controversial, and that observational support for the theory is just now trickling in, an no one has any idea what the heck it even IS.

Then again, this is a channel that regularly runs silly supernatural phenomena shows.

Re:I love it... except I don't (1)

zippthorne (748122) | more than 6 years ago | (#22576154)

Then again, this is a channel that regularly runs silly supernatural phenomena shows.
Yeah, but in that genre, ironically, the sillier they are, the less stupid they are. In the limit of a bunch of cranks making fun of people who believe in ghosts being the just about the least stupid possible "ghost hunting" show.

Re:I love it... except I don't (0)

Anonymous Coward | more than 6 years ago | (#22576034)

And yet you still came here and read it anyway. Even commented on it.

I guess severe nausea doesn't necessarily stop someone from being a complete douchebag after all.

If you're on Slashdot looking for facts, you're on the wrong website.

Re:I love it... except I don't (1)

FUD spreader (1153607) | more than 6 years ago | (#22576042)

Misinformation makes you angry. When you tell me you want to puke after you walk in on your mom giving your dad (what I later learned was called) the rusty trombone, THEN I feel sympathy for you - not before.

Re:I love it... except I don't (1)

MightyYar (622222) | more than 6 years ago | (#22576324)

rusty trombone
Ouch. Kind of turns around the phrase: "Do you kiss your mother with that mouth?", doesn't it?

Re:I love it... except I don't (1)

nacturation (646836) | more than 6 years ago | (#22576184)

I love it when all these theories get presented as fact.
What? Are you trying to these theories don't exist? :)
 

Sheets and Filaments (4, Insightful)

TheEmptySet (1060334) | more than 6 years ago | (#22575902)

So we are to understand that dark matter, acted on only by gravity, forms sheets and filaments? We know very well what shapes distributions of particles form over time with only gravity acting on them and they look a lot like galaxies and very little like sheets and filaments. Can anyone clear this up for me?

Re:Sheets and Filaments (4, Interesting)

KublaiKhan (522918) | more than 6 years ago | (#22576028)

Kind of an odd thing to do, isn't it?

However, galaxies also form 'sheets and filaments' at extremely large scales, as well; presumably, should these folks figure out how to find smaller structures, they should look somewhat more familiar.

Re:Sheets and Filaments (5, Informative)

JustinOpinion (1246824) | more than 6 years ago | (#22576090)

First, remember that the distribution of dark matter and ordinary matter are, actually, pretty similar (we find galaxies accumulated along the dark matter filaments, and at smaller scales see dark matter concentrated into galaxies).

Second, my understanding is that dark matter (whatever it is) must be fairly weakly-interacting. The normal matter that we see aggregating into stars and galaxies interacts with itself (the particles bounce off each other, exchanging momentum, and also they repel each other at very short distances). This interaction, in addition to gravity, dictates the shapes we see for ordinary matter.

Dark matter doesn't interact strongly (with matter, and presumably with itself), so it aggregates differently. Imagine a cluster of dark matter that is being gravitationally collapsed: as the particles get closer to each other, instead of bouncing off each other (and thereby e.g. transforming their large-scale kinetic energy into heat), they 'pass through' each other (actually just pass by each other without scattering). This means that the matter will aggregate differently (the dark matter particles will mutually gravitate and orbit, but can't coalesce).

I'm painting a simplistic picture, but the point is that there are some fundamental differences about how dark matter interacts, versus ordinary matter. I believe the filamentary structure itself is an artifact of the universe's inflationary epoch, where massive expansion has amplified small-scale quantum fluctuations into the very large-scale distribution we now see.

Re:Sheets and Filaments (3, Interesting)

KublaiKhan (522918) | more than 6 years ago | (#22576274)

It may be possible that dark matter interacts normally with itself, but its weak interaction with what we can see makes the problem of resolution difficult.

If I were feeling particularly sci-fi, I'd probably call it something like 'gravitational bleed-over from close neighboring dimensions'.

Re:Sheets and Filaments (5, Informative)

exp(pi*sqrt(163)) (613870) | more than 6 years ago | (#22576800)

> We know very well what shapes distributions of particles form over time with only gravity acting on them and they look a lot like galaxies and very little like sheets and filaments.

No. When we try to predict the large scale distribution of matter using simulations [physorg.com] we get filaments.

pounced upon? (5, Funny)

Numbah One (821914) | more than 6 years ago | (#22575906)

so the scientists are lol cats? Oh, hai drk mater! i pownse on u!

When LOLcats attack (1, Funny)

eviloverlordx (99809) | more than 6 years ago | (#22576012)

We r in ur universe, messin with ur drk mattr sheetz.

Re:When LOLcats attack (1)

EntropyXP (956792) | more than 6 years ago | (#22576120)

Invisible sheetz of drk matterz

Re:When LOLcats attack (1)

syrinx (106469) | more than 6 years ago | (#22576192)

mai dark mattr sheetz, let me show you them

Re:pounced upon? (1, Offtopic)

spun (1352) | more than 6 years ago | (#22576212)

Dark mater cat is DARK!

I can has cosmic string?

Proof of dark mater? We has it!

Re:pounced upon? (0)

Anonymous Coward | more than 6 years ago | (#22577040)

im in yur slshdots modin u dwn

Re:pounced upon? (1)

Himring (646324) | more than 6 years ago | (#22576870)

oh n0z! sed t3h drk materz. r g4l4x3is r t3h m3ltz!...

Re:pounced upon? (4, Funny)

Anonymous Coward | more than 6 years ago | (#22577034)

Lots of scientists are lol cats, remember Schrödinger's lolcat? I can has superposishun?

The Rubber sheet analogy is WRONG!!! (5, Interesting)

jameskojiro (705701) | more than 6 years ago | (#22575920)

The whole rubber sheet of space time analogy is wrong, it is missing something.

Current analogy of space time:

Take a rubber sheet and stretch it out over a frame and drop a bowling ball and marble and drop them on it, they push down and those dents are gravitation fields in space-time.

New more correct analogy:

Take a swimming pool and fill it all the way to the top with water. THEN, stretch a rubber sheet over it and seal it so that no water leaks out. Then put your bolwing ball and marble on it. Draw a line running between the bowling ball and marble, and take that cross section, note that the bowling ball and marble behave the same way at close distance like they do above, but when they are a opposite sides of the pool there is a slight "repulsive" effect. We call that Dark Energy! This repulsive effect also can help stick objects together applying a "pressure" against all the other objects, hence "Dark Matter". This effect will also affect light waves moving past it, hence gravitational lensing.

I'll take my Nobel prize now!

Re:The Rubber sheet analogy is WRONG!!! (4, Funny)

Wandering Wombat (531833) | more than 6 years ago | (#22576010)

Scientists never get invited to pool parties... you're just making them feel bad now.

Makes a lot of sense, though.

Re:The Rubber sheet analogy is WRONG!!! (4, Funny)

TobyRush (957946) | more than 6 years ago | (#22576150)

Scientists never get invited to pool parties...

And there's good reason. I grew up in Los Alamos, NM, and the best part about doing our swimming merit badges at the county pool was having the dad of one of the scouts -- a LANL physicist -- come early to pick up his son. He'd have all of us at the shallow end of the pool, and he'd be standing there holding a pendulum. Based on the pendulum's swing, he'd either yell "jump in!" and we'd all jump in simultaneously, or "get out" and we'd all get out simultaneously. After doing this for four or five minutes, the entire pool was sloshing back and forth, spilling over onto the deck on each end, getting everyone's towels wet if they weren't on the bleachers.

We thought it was awesome. The lifeguards didn't.

Re:The Rubber sheet analogy is WRONG!!! (1)

Wandering Wombat (531833) | more than 6 years ago | (#22576222)

This is very true... I destroyed an above-ground pool that way when I was younger (sort of like the YouTube of the guy bouncing in the middle of the pool, only this one tore itself apart before I got NEARLY that high...)

Re:The Rubber sheet analogy is WRONG!!! (1)

Belial6 (794905) | more than 6 years ago | (#22576960)

Do you have a link for this? I looked up "guy bouncing in the middle of pool" and couldn't find anything.

Re:The Rubber sheet analogy is WRONG!!! (3, Interesting)

jameskojiro (705701) | more than 6 years ago | (#22576124)

Oh almost forgot the water pressing back upwards is like the way space time relieves the stress of having massive objects concentrated in one area. You press down on one area of space time and space time bulges out in another more distant area. It is like the packing dilema try putting 1000 ping pong balls in a box that can only hold 999, when you put int he last one and force it in, it will push another one out.

If you took all the matter in the universe and spread it out evenly, it would put the same "pressure" against space time, like a uniform sheet or membrane, make a large enough disturbance and all that matter will start flowing to one area and the sheet will stretch till it hit the bottom of the pool and rebounds, hence the Big Bang.

Re:The Rubber sheet analogy is WRONG!!! (2, Funny)

VultureMN (116540) | more than 6 years ago | (#22576608)

For proper Slashdot credit, transform your analogy so it involves a car.

You have 10 minutes.

Re:The Rubber sheet analogy is WRONG!!! (5, Informative)

JustinOpinion (1246824) | more than 6 years ago | (#22576230)

The "rubber sheet" analogy is imperfect, but I don't think your revised analogy is correct.

Draw a line running between the bowling ball and marble, and take that cross section, note that the bowling ball and marble behave the same way at close distance like they do above, but when they are a opposite sides of the pool there is a slight "repulsive" effect. We call that Dark Energy!
"Dark energy" doesn't mean that normal matter is repulsive at large distances. Ordinary matter is always gravitationally attractive towards other ordinary matter, at all scales. Same for dark matter (whatever it is). "Dark energy" is, in fact, a "negative pressure" that pushes on spacetime itself, causing the universe to expand (and moreover gets stronger and stronger the lower its density becomes).

If dark energy sounds counter-intuitive: it should! Of course we don't really know what it is (yet), but the experimental evidence available thus far does not suggest that matter is repulsive at large distances, but rather that "something" fills spacetime and exerts an expansion force that is inversely proportional to its density.

This effect will also affect light waves moving past it, hence gravitational lensing.
Just to be clear: gravitational lensing also has nothing to do with dark energy... and nothing to do with dark matter specifically. Any source of gravity (ordinary matter, dark matter, etc.) will deflect the path of light rays (the effect is small but measurable). Thus gravitational lensing is a great way to determine the "amount of mass" within a volume of space. When that mass is correlated with brightness, we say it's ordinary matter (stars, etc.) and when that mass is correlated with seemingly empty patches of space (dark), we call it dark matter.

Re:The Rubber sheet analogy is WRONG!!! (1)

jameskojiro (705701) | more than 6 years ago | (#22576536)

Dark Energy could also be seen as an anomoly in space time rather than something with substance or some wierd particle of the leaking through of a higher dimension.

Re:The Rubber sheet analogy is WRONG!!! (1)

tmosley (996283) | more than 6 years ago | (#22577046)

I would say that the rubber sheet analogy still holds, because there are two forces working on the sheet. The first is gravity, which is attractive at all distances (the balls on the sheet still create a path of least resistance between each other). The other force is that of the displaced water pushing up everywhere on the sheet evenly. At close distances, gravity wins, while at great distances, dark energy wins.

I would be interested to see if this analogy holds further and shows that the universe is in fact stretched across some sort of fluid so as to act in this way.

Re:The Rubber sheet analogy is WRONG!!! (1)

kilo1 (1239544) | more than 6 years ago | (#22576382)

Agreed, the water analogy makes much more sense!

Re:The Rubber sheet analogy is WRONG!!! (1)

jameskojiro (705701) | more than 6 years ago | (#22576444)

More of a rubber sheet over sealed water pool.

You forgot spacetime dragging. (1)

Tatarize (682683) | more than 6 years ago | (#22576466)

Before covering it with the rubber be sure to have a bunch of friends jump in and run around in a circle to create a whirlpool effect like what might easily be seen if you had the vast majority of galactic mass swirling around in a galaxy.

Re:The Rubber sheet analogy is WRONG!!! (1)

EntropyXP (956792) | more than 6 years ago | (#22576542)

So in your analogy, is a blackhole like a drain at the bottom of the pool? Gravity so strong that even the "water" (dark matter) gets sucked in as well?

Re:The Rubber sheet analogy is WRONG!!! (1)

j-stroy (640921) | more than 6 years ago | (#22577130)

Nice description! Similar to the 3 blind men and the elephant.. Anyhow, hope I get this right, what you are describing is what I've heard called a scalar field. That is something like atmospheric air pressures, measured at many points. Despite the fact that there is no original vector forces, motion (wind) is created through the differences in the scalar values. So the implication is that space-time is under some sort of static tension. The question then is what things affect that tension and whether there is regional or temporal variance.

Thread Count? (3, Funny)

Anonymous Coward | more than 6 years ago | (#22575924)

So what's the thread count on these sheets? And no weaving multiple superstrings at a time to inflate the number please...

Pounced upon? (1, Funny)

winkydink (650484) | more than 6 years ago | (#22575928)

WTF? Were the scientists wearing kitten costumes?

Re:Pounced upon? (0)

Anonymous Coward | more than 6 years ago | (#22577172)

Clearly you don't know many people who devote their lives to science, kitten costumes aren't that far outside the scope of possibility.

How can they tell this is caused by Dark Matter? (0)

Anonymous Coward | more than 6 years ago | (#22575996)

So they're seeing a slight lensing of distant objects and putting this down to dark matter? At those distances does the dark matter move enough to alter the light that much? I would have thought that even with adaptive optics, this would be within the margin of error of our own atmosphere's lensing.

Re:How can they tell this is caused by Dark Matter (0, Redundant)

orclevegam (940336) | more than 6 years ago | (#22576218)

I would have thought that even with adaptive optics, this would be within the margin of error of our own atmosphere's lensing.
I was kind of thinking the same thing. Seems like if they're seeing distortion then occam's razor would tend to dictate it's coming from the instruments used to do the measuring. Of course, if they can prove the distortion isn't being caused by the instruments, or other interference, they still need to prove that some other known property doesn't explain the distortion.

Re:How can they tell this is caused by Dark Matter (3, Insightful)

Big_Breaker (190457) | more than 6 years ago | (#22576370)

You are throwing up your hands WAY too soon and crying occam's razor.

Atmospheric distortions are not consistent over time or different locations and those distortions do not "lense" like gravity does. Also standard astronomic technique is to have someone confirm your results with a different telescope, in a different part of the world.

It may not be dark matter, but it's not a smudge on their mirror either.

Re:How can they tell this is caused by Dark Matter (0)

Anonymous Coward | more than 6 years ago | (#22576844)

You are throwing up your hands WAY too soon and crying occam's razor.

The same way the scientists are crying dark matter.

It may not be dark matter, but it's not a smudge on their mirror either.

The point being that it could be any number of other things.

Re:How can they tell this is caused by Dark Matter (2, Informative)

JustinOpinion (1246824) | more than 6 years ago | (#22576644)

The evidence for gravitational lensing is much stronger than that. In the most extreme images, we can actually see multiple images of a single source. In this image [wikimedia.org] , there are four copies of the distant quasar because of the lensing of the closer galaxy (center of image). Even though gravitational lensing is a fairly small effect, given the massive distances we're talking about, the deviations are readily measurable.

Also, many of the measurements come from Hubble images, for which there is no atmospheric turbulence to deal with (atmospheric effects also average-out over a fairly short period of time, and though they decrease resolution they are easy to differentiate from astronomical sources of distortion).

The error bars are small enough that we know the light from distant sources is being deflected. The simplest explanation is that there is a cluster of mass between us and the source, whose gravity is deflecting the light.

Re:How can they tell this is caused by Dark Matter (1)

exp(pi*sqrt(163)) (613870) | more than 6 years ago | (#22576856)

> I would have thought...

What does "I would have thought" have to do with anything? Have you actually performed the calculations to work out how much lensing you'd expect to see from atmospheric effects and compare that with gravitational lensing?

Xenu! (1)

Zephurus (1204434) | more than 6 years ago | (#22576092)

Aha..so that's where Xenu is hiding...call Tom Cruise, quick!

Exciting Stuff.... (1)

MrKane (804219) | more than 6 years ago | (#22576204)

...I assume dark matter/energy will make more sense if and when we can unify the relativity & quantum theories?

I say this only because dark matter is "seen" by it's effects on other particle due to it's gravitational properties,
not it's electromagnetic properties, ie, light doesn't interact directly with it, hence "dark".

...come on LHC, give us the HiggsBoson damn you! ;?)

It May Be Dark... (1)

Nom du Keyboard (633989) | more than 6 years ago | (#22576264)

It may be dark, and it may be matter, but it's clearly pretty darn transparent to light and other electromagnetic frequencies we are observing.

Giant what? (1)

bluefoxlucid (723572) | more than 6 years ago | (#22576484)

Giant invisible sheets of what the fuck? So are we like in the Kingdom Hearts universe now where different sections of the universe have an invisible separating barrier between them and Goofy lives somewhere in the next galaxy?

Re:Giant what? (1)

jameskojiro (705701) | more than 6 years ago | (#22576586)

Yay, I guess instead of going to "pretend DisneyLand" in Florida, we can make a space ship and go to "REAL Disney Land"!!!

I wanna shoot bambi while I am there and exploit their cartoony resources, I will do a better job wrecking the place because i will be less of a cartoony villian and more of an effective villian like Bill Gates.

Wow... (1)

rickb928 (945187) | more than 6 years ago | (#22576656)

This is as close to making it up as Physics has gotten in a while. Feh.

Really, I'm waiting for the face they find on one of the sheets.

Holly? is that you? (2, Funny)

russ1337 (938915) | more than 6 years ago | (#22576718)

Because the dark matter, by definition, is invisible to telescopes.....
Reminds me of a certain Red Dwarf episode (obviously discussing Black holes instead of Dark Matter):

Holly: Well, the thing about a black hole - its main distinguishing feature - is it's black. And the thing about space, the colour of space, your basic space colour, is black. So how are you supposed to see them?
Rimmer: But five of them? Five massively collapsed stars, millions of miles across. How could you miss them?
Holly: It's typical, isn't it? You wait three million years with nothing, then five come along all at once.

cool (1)

Madcapjack (635982) | more than 6 years ago | (#22576926)

Cut out a couple of holes and you've got a cool Halloween costume.

Gravity, it is wrong (5, Interesting)

sweetser (148397) | more than 6 years ago | (#22576932)

Or at least our current mathematical description of it is wrong. We cannot explain how disk galaxies spin. We cannot explain how the big bang happens without the magic fairy dust for inflation. Now we have a large wall of dark matter. Oh, and there is dark energy for galaxy acceleration. One more thing, we cannot quantize our approach to gravity.

These are the reasons I work on a rank 1 field theory for gravity. For the details, read as much of this thread as you like: http://physicsforums.com/showthread.php?t=87097 [physicsforums.com] This is a LONG thread, more than 36k views, I make learn things along the way. Right now I am trying to find derive the Maxwell equations, and then the unified field theory, instead of using tensors. Quite a bit of fun. I have never had to write so many partial differential equations in my life.

Doug

the Shadows in Bablyon 5 ... (1)

peter303 (12292) | more than 6 years ago | (#22576946)

are real!

Alternatives sound way more realistic... (0)

Anonymous Coward | more than 6 years ago | (#22577080)

Or am I the only one who finds the whole Dark Matter thing too 'exotic'?


Thunderbolts of the Gods [google.com]


The Electric Sky: Donald E. Scott [youtube.com]


The Electric Universe [youtube.com]


Electric universe/plasma cosmology ftw~

But not Europe, do not colonize there (1)

billcopc (196330) | more than 6 years ago | (#22577098)

Did someone say "Monolith" ?
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