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Chandra Provides Support For Dark Energy

timothy posted more than 10 years ago | from the dark-and-forth dept.

Space 350

starannihilator writes "The Chandra X-Ray Observatory has provided new evidence supporting the existence of dark energy, the force causing the acceleration of universal expansion. The new findings support the theory that the universe will expand forever, provided there is enough dark matter. CNN and Newsday are running the story, originally reported by NASA. Chandra's site has some good images and information on the three galaxies clusters studied (Abell 2029, MS2137.3-2353, and MS1137.5+6625)."

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Lame pics. (-1, Offtopic)

grub (11606) | more than 10 years ago | (#9195248)


Chandra's site has some good images

Bah, those just look like the goatse guy in a dark room, not quite wallpaper quality for my desktop.

Pretty good pics (1, Funny)

Chuck Chunder (21021) | more than 10 years ago | (#9195301)

Considering they are pics of things between 1 billion and 6 billion light years away.

If only the goatse guy was that far from the camera in that photo.....

Israel: racist butchers. (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#9195331)

Serves the Palestinian rabble right (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#9195487)

So what?

Why are you left-wing whingers - particularly here in Europe - so concerned about the palestinians anyway?

Israel is the only democracy in the middle-east and they are God's chosen people. Palestinians are just reaping the results of working against God's will and worshipping pagan gods.

NEWSFLASH god is dead (1)

Mike Hock (249988) | more than 10 years ago | (#9195643)

And if he was alive he would probably hate israel, you and your cocksucking comments!

Thank You

Re:Serves the Palestinian rabble right (-1, Flamebait)

Anonymous Coward | more than 10 years ago | (#9195671)

I'm concerned for people, doesn't matter what their race is. When fuckheads like you start bringing religion into the mix people die.

Fuck religion and fuck you.

Dark matters (5, Funny)

Allen Zadr (767458) | more than 10 years ago | (#9195260)

I am eagerly awaiting the next annoncement where someone again finds evidence to refute the dark matter claims. It seems like the science; "Dark Matter is like this" - "No, it can't be, actually it's like that". Is not going to end soon.

Join me. Come to the dark side, and together, we will expand the universe.

Re:Dark matters (1, Insightful)

Mz6 (741941) | more than 10 years ago | (#9195304)

No kidding...

Why can't scientists just make up their minds already?

First it's not expanding, now it is... Oh well now it's slowing down again, and now expanding agian.

I also see no end in sight...

Re:Dark matters (2, Informative)

Allen Zadr (767458) | more than 10 years ago | (#9195386)

Thank you for getting my point. Just following the /. stories since February... Now, with this story, it's back again.

Re:Dark matters (1, Insightful)

Anonymous Coward | more than 10 years ago | (#9195445)

Seperate paths with conclusions you could make with that data put on them, ultimatly you'd want them all to be explained by a single theory. Or in other words, all the good measurements need to be accounted for. Incidentally, we know there is some dark matter out there, afterall anything that's pretty dark as in doesn't shine or doesn't reflect much light is dark matter. Just how much, well that's what they're arguing over.

Quickshot

Re:Dark matters (4, Insightful)

Too Much Noise (755847) | more than 10 years ago | (#9195477)

It's not that simple. Cosmology is now in a position pretty much similar to that of a butterfly trying to understand the passing of seasons. Moreover, as the name says, "dark" matter/energy is undetectable directly (at least, so far) - and it's quite challenging to figure out a 'simple' theory for something that not only you can't observe directly, but the indirect observations are difficult and not always very accurate.

Anyway, since it's not very likely that the knowledge of dark matter will have a significant impact on the daily life anytime soon, relax and enjoy the (slow-moving) show.

"Dark matter" != "Dark energy" (5, Informative)

Short Circuit (52384) | more than 10 years ago | (#9195621)

Uh, dark matter [wikipedia.org] and dark energy [wikipedia.org] aren't the same thing.

Re:Dark matters (4, Funny)

Jim Starx (752545) | more than 10 years ago | (#9195391)

God made the universes expansion a sine wave just to piss scientists off.....

Re:Dark matters (4, Insightful)

hazem (472289) | more than 10 years ago | (#9195645)

Why can't scientists just make up their minds already?

Because if they did, they'd be theologians, not scientists.

Re:Dark matters (2, Funny)

eviloverlordx (99809) | more than 10 years ago | (#9195368)

Do not underestimate the power of the dark, uh, energy?

Re:Dark matters (3, Informative)

sjwaste (780063) | more than 10 years ago | (#9195572)

As others have said, accelerating expansion means that objects very distant are moving away from us faster than closer objects are moving away from us. If you have time for some interesting reading, I'd recommend a title called Atom [amazon.com] which is very readable and is a good primer on theory from the big bang to present time. It won't answer many questions about dark energy, but if anything, it'll give you a good idea of what we know in very readable terms and most likely get you to want to read more :) It was my first book on the subject, and it certainly had that effect. Note that I'm no physicist, just a curious reader.

Hmm that name sounds familiar (4, Funny)

Nuclear Elephant (700938) | more than 10 years ago | (#9195269)

I dated a girl named Chanda once. Dark energy is a good way to describe her.

Re:Hmm that name sounds familiar (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#9195294)

+2 Offtopic.

Re:Hmm that name sounds familiar (1)

Nuclear Elephant (700938) | more than 10 years ago | (#9195344)

well, I meant Chandra - if I had spelled it right, it would've been +2 Funny.

Re:Hmm that name sounds familiar (0)

Anonymous Coward | more than 10 years ago | (#9195444)

What's one letter among atomic powered pachyderms?

Re:Hmm that name sounds familiar (-1, Redundant)

Anonymous Coward | more than 10 years ago | (#9195448)

I did too, I left her corpse in a park ;)

Chandra == Moon (0)

Anonymous Coward | more than 10 years ago | (#9195537)

Chandra is the word in many Indian languages for the Moon.

Re:Hmm that name sounds familiar (0)

Anonymous Coward | more than 10 years ago | (#9195567)


Yeah, she got married and then she "expanded".

MS at it again (0, Offtopic)

sheeny (730803) | more than 10 years ago | (#9195278)

Are those last two patented by Microsoft?

Re:MS at it again (0)

Anonymous Coward | more than 10 years ago | (#9195343)

no, if that were the case it would be .ENERGY written in the dark

So the Jedi are right (0, Offtopic)

ospirata (565063) | more than 10 years ago | (#9195285)

Befora Chandra X-Ray observatory, in a galaxy far far away, the Jedi have already proven the dark side of the force (same as dark energy) and controlled it.

Dakr Matter (4, Interesting)

Mz6 (741941) | more than 10 years ago | (#9195289)

Maybe someone can explain... But when the CNN article states that the universe is "accelerating", does that mean it's really accelerating? I thought it was decided that the universe's expansion was expanding at the speed of light. So, I would assume that by accelerating they mean growing bigger and not actually accelerating faster than the speed of light. Unless, this Dark Matter is something that can bend the known laws of physics and travel faster than the speed of light?

Re:Dark Matter (3, Insightful)

fr2asbury (462941) | more than 10 years ago | (#9195327)

If the universe was expanding at the speed of light. It would look pretty dark out there at night.
Or at the very least it would be awfully hard to see some of those distant galaxies.

the universe was expanding at the speed of light (4, Funny)

Allen Zadr (767458) | more than 10 years ago | (#9195561)

Don't you get your science from Monty Python movies. It was explained quite succinctly, in the Meaning of Life.

Whenever life get's you down, Mrs. Brown
and things seem hard and tough,
and people are stupid, obnoxious or daft,
and it feels that you've had quite enough---

Just remember that your standing on a planet that's evolving,
revolving at 900 miles per hour.

It's orbiting at 19 miles per second, so it's reckoned,
a sun that is the source of all our power.

The sun, and you and me and all the stars that we can see
are moving at a million miles a day,
in an outer spiral arm at 40,000 miles an hour,
in this galaxy we call the milky way.

The galaxy itself contains 100 million stars,
it's 40 thousand light years side-to-side.
It bulges in the middle 30 thousand light years thick,
but out by us it's just 3000 light years wide.
We're 30 thousand light years from galactic central point,
we go round every two hundred million years
And our galaxy is only one of millions and billions
in this amazing and expanding universe.

Musical interlude

The Universe itself keeps on expanding and expanding
in all of the directions it can whizz.
As fast as it can go, the speed of light, you know
A million miles a minute and that's the fastest speed there is.
So remember when your feeling very small and in-secure,
how amazingly unlikely is your birth.
And prey that there's intelligent life, somewhere out in space,
'cause there's bugger-all down here on Earth.

Attribution for the above lyrics to Eric Idle.

But seriously... (2, Interesting)

Allen Zadr (767458) | more than 10 years ago | (#9195624)

Supposedly, the "edges" of the universe are expanding outward at the speed of light. The rest of the universe is slower, until you meet the - so-called - center which is a virtual stand-still.

I should point out here that it's also been theorized that the center is in fact pulling things back in - but this is an old theory, that hasn't gotten much press lately.

The accelleration of the expansion is about the inner layers of the universe accelerating to match (more closely) the speed of the outer edge.

So, it's not really acceleration beyond the speed of light, but an accelleration of the slower contents within the universe.

Think of an empty baloon in a centrafuge. The heat will make the baloon expand, and as the spinning keeps moving, the inside air will press harder against the sides - causing more heat and more expansion. The air that's not at the outside is going to "catch up" to the air at the edges.

Of course, this needs to be adjusted to understand that the "balloon" has no outer bounds, isn't going to pop, and has a near infinate amount of matter inside..

Re:Dark Matter (1, Informative)

solarlux (610904) | more than 10 years ago | (#9195565)

Recall that Hubble's law is v=H*D where v is the velocity a given galaxy is moving away from us and D is its distance from us (and H is Hubble's constant). So closer galaxies are moving more SLOWLY away from us than distant galaxies. And hence, closer galaxies may be moving away slower than c while more distant galaxies may be moving away faster than c.

Re:Dakr Matter (2, Interesting)

Jim Starx (752545) | more than 10 years ago | (#9195330)

The universe can't be expanding at the speed of light. Releativity states that the speed of light is as fast as it gets. So if we were all going the speed of light away from the center of the universe there would be no headroom in the velocity for movement in any other direction. That would mean planet orbits, even walking down the street in a certain direction would be impossible.

Re:Dakr Matter (3, Insightful)

llamaguy (773335) | more than 10 years ago | (#9195362)

Consider for a moment that Einstein might have been wrong? Since we can't actually study anything at the speed of light properly, it's all down to the calculations and even great minds might make errors. So, you never know...

Re:Dakr Matter (2, Interesting)

Jim Starx (752545) | more than 10 years ago | (#9195418)

Very true.... but if einstien is wrong that breaks open a whole can of somethin. Consider all the observations that are based on einstein's theories. Possibly even these observations.... definitly something to think about.... preferably by someone smarter then me...

Re:Dakr Matter (1)

llamaguy (773335) | more than 10 years ago | (#9195462)

Consider all the observations that are based on einstein's theories Point, but everything has several explanations depending on how you look at it. If something falls over, did a sudden gust of wind knock it over or did a supernatural power? Both are equally possible within the phase space, but only one solution. People would've actually believed that it was the work of a ghost for a while, but now (most) of us reckon that it was a gust of wind. The same principle applies to scientific observations. Course, I'm not saying that Einstein was wrong or not, I'm saying there is the possibility he was.

Re:Dakr Matter (2, Insightful)

CodeMonkey4Hire (773870) | more than 10 years ago | (#9195467)

Hell, Newton was "wrong," but it wasn't the end of the world. In fact, the corrections to his theories led to some amazing discoveries. I would imagine that any theories that "prove" Einstein wrong will lead to some amazing technology themselves. Of course such speculation leads to... Science Fiction (I am not saying it would be wrong - remember that flying to the moon used to be scifi).

Re:Dakr Matter (2, Insightful)

sindarin2001 (583716) | more than 10 years ago | (#9195627)

Not only that, but I daresay there is no "correct" theory. Genius after genius creates a model that describes an ever increasingly complex universe, and then a new odd discovery throws a monkey wrench into the theory. The theory isn't really wrong, it's just no longer all-encompassing like we previously thought.

That said, sometimes a theory can be just plain wrong.

Re:Dakr Matter (4, Informative)

barawn (25691) | more than 10 years ago | (#9195367)

Releativity states that the speed of light is as fast as it gets. ... for matter. Relativity makes no such claims as to the speed limit of space itself.

There are quite a number of valid GR metrics which describe space which expands faster than the speed of light, and in fact, it's thought that it did expand faster than the speed of light during the inflationary period.

Those same metrics are the basis of the Alcubierre metric, one of many ways to generate faster-than-light travel without multiply-connected spacetimes (wormholes). Like most "violate the speed of light" metrics, it requires negative energy density matter, though variations on the metric allow for very tiny amounts of negative energy matter to generate it.

Re:Dakr Matter (0, Troll)

savagedome (742194) | more than 10 years ago | (#9195332)

bend the known laws of physics and travel faster than the speed of light?

A particle cannot *accelerate* past the speed of light. A particle, like photon, can travel faster than the speed of light as they are already traveling at the speed of light to begin with. Speed of light is the acceleration barrier.

Re:Dakr Matter (1)

Jim Starx (752545) | more than 10 years ago | (#9195372)

What's the diffrence?

Re:Dakr Matter (-1)

Anonymous Coward | more than 10 years ago | (#9195388)

WTF? That sounds like pot laws in some places... It's perfectly legal to be stoned, just not have any on you.

Re:Dakr Matter (4, Interesting)

barawn (25691) | more than 10 years ago | (#9195420)

Speed of light is the acceleration barrier.

This isn't even strictly true. You can violate global speed-of-light travel times without violating local speed-of-light travel times by making space itself move - see the inflationary period, or the Alcubierre metric for more info.

You can imagine it as a speed limit placed on people walking, but there is no such speed limit on moving walkways (like in airports).

And the problem with particles traveling faster than light (tachyonic) is the fact that as they *lose* energy, they go faster, which makes them lose more energy, so they spiral out to infinite speed. Tachyonic modes are unstable, so a theory containing them typically undergoes tachyonic condensation (spontaneous symmetry breaking) and the tachyons gain a positive mass squared.

Re:Dakr Matter (1)

wwest4 (183559) | more than 10 years ago | (#9195425)

> A particle, like photon, can travel faster than the speed of light as they are
> already traveling at the speed of light to begin with.

I've never heard of the possibility for a photon to travel faster than c, where c is speed of light in vacuum. What is the basis for this? Also, does a photon ever really accelerate anyway? Do bosons and fermions really have the same relativistic physics?

Re:Dakr[sic] Matter (3, Funny)

D-Cypell (446534) | more than 10 years ago | (#9195566)

I have a particle around here somewhere that I measured to find its precise speed was very slightly faster than c.... I would show it to you as proof but I cant seem to find it anywhere! ;o)

Re:Dakr Matter (1)

CodeMonkey4Hire (773870) | more than 10 years ago | (#9195431)

Actually, photons can not travel faster than the speed of light - they are light. Although theorectically possible, we have never detected any particle that can travel FTL. However, we have already named them tachyons.

Re:Dakr Matter (1, Interesting)

Anonymous Coward | more than 10 years ago | (#9195435)

Not true, it takes an infinit amount of energy to accelerate to the speed of ligth, to accelerate any faster, even if a particle started at the speed of light, would still require an infinite amount of energy.

Re:Dakr Matter (3, Informative)

wwest4 (183559) | more than 10 years ago | (#9195339)

> I thought it was decided that the universe's expansion was expanding at the
> speed of light

I don't think the acceleration in on the order of c^2, if that's what you mean. What they mean is that due to acceleration, some space (the stuff that's furthest away) is expanding at close to c.

Re:Dakr Matter (1)

Saluton_Mondo (728648) | more than 10 years ago | (#9195377)

More distant objects are moving away from us more rapidly than the local ones... i.e. objects further away appear redder because of the redshift: that is, the wavelength of radiation from a body appears longer (redder) that its restframe emission because it is travelling with some velocity away from us.

Re:Dakr Matter (2, Informative)

cruachan (113813) | more than 10 years ago | (#9195383)

The speed of light is only a restriction upon the velocity of matter/energy within space-time. There is no such restriction upon the expansion or movement of space-time itself. If you think about it in the usual 'rubber sheet' model then this is equivalent to saying that particles on the surface of the sheet can only travel up to c, but that the sheet itself can change without such restrictions.

This is effectively how the Alcubierre warp drive works.

Re:Dakr Matter (2, Informative)

the_2nd_coming (444906) | more than 10 years ago | (#9195387)

the Universe can expand FASTER than the speed of light. Relativity says matter and energy can not travel faster than the speed of light through space-time, but when talking about dark energy and the expansion of the universe, we are talking about the expanding of space between galaxies, so the galaxies, relative the their local space are not traveling near the speed of light, but relative to inter galactic space, they are.

Expansion of universe (5, Informative)

hcg50a (690062) | more than 10 years ago | (#9195393)

I thought it was decided that the universe's expansion was expanding at the speed of light.

No. The expansion of the universe refers to the fact that distant galaxies are moving away from us, and that the farther they are, the faster they are moving. This is expressed by the Hubble constant [utk.edu] , which has a value of about 50 km/s/Mpc.

The acceleration of the expansion is reflected as this "constant" increasing with increasing distance.

The acceleration is caused by Dark Energy, not Dark Matter.

Dark Matter is either normal matter or subnuclear matter that makes its presence felt as increased gravity, but is not directly observable.

Dark Energy is not well understood at all.

Re:Dakr Matter (4, Informative)

Betelgeuse (35904) | more than 10 years ago | (#9195402)

Yes. The universe is accelerating in its expansion. To say that the universe is expanding "at the speed of light" isn't quite right in a couple of ways. First off, if we look at objects nearby, they are moving away from us at some (quite reasonable) finite speed (i.e. the nearby Virgo Cluster is moving only at ~1000 km/s). Secondly, the somewhat more subtle point is that we generally talk about velocites not exceeding the speed of light; however, this is motion THROUGH space. The expansion of the universe (expansion OF space) doesn't necessarily need to follow this rule. . .

I should also point out that "Dark Matter" and "Dark Energy" are COMPLETELY DIFFERENT THINGS (as far as we know). Astronomers have just named them both "Dark" because they don't know what they are. They both also affect the expansion of the universe, but dark matter is slowing down the expansion of the universe (presumably via gravity) and dark energy is accelerating the expansion of the universe (by some yet-unknown force). Dark Matter is weird, but at least it seems to sortta obey the rules of the universe (i.e. gravity); dark energy is completely unlike anything we've seen before.

Re:Dakr Matter (3, Informative)

CodeMonkey4Hire (773870) | more than 10 years ago | (#9195411)

(1) the universe is not expanding at the speed of light (I think that it is less)
(2) the space-time fabric of the universe is not an object anyway, so FTL rules do not apply

It is actually possible for 2 objects to move apart faster than the speed of light even though neither is moving FTL compared to the other. This statement seems to be nonsensical, until you realize that the expansion is a 4D effect. Think of the galaxies (in 2D) as though they were on the surface of a balloon (2D). Now imagine the balloon getting larger (3D effect) at the same time that galaxies are moving farther apart. Now use that analogy with 1 higher dimension. The 2 effects are independent, but both contribute to increasing distance between galazies. As my physics professor once said "Everywhere is getting farther apart."

BTW, this is why the wavelength of the cosmic radiation is getting longer. The cosmic radiation is actually getting stretched (along with everything else) along with the universe. So while the frequency & energy stay the same, the cosmic radiation gets "red-shifted." And since they can surmise the starting wavelength (from Hydrogen energy levels), they can make predictions based on that too.

Re:Dakr Matter (1)

freshtonic (650437) | more than 10 years ago | (#9195491)

Actually, red-shifting can be explained without resorting to space-time being stretched. But space-time stretching *will* contribute to a red-shift. Objects flying apart at significant fractions of C will exhibit redshift when observing one object from the other regardless of whether the space in between is 'getting bigger'. My head hurts.

Re:Dakr Matter (1)

CodeMonkey4Hire (773870) | more than 10 years ago | (#9195605)

I'm sorry. I didn't mean to imply that this is the cause of red-shift. As you pointed out there is another explanation for redshift, the Doppler effect (for the benefit of those who need it - probably not you freshtonic). This is what usually redshifts/blueshifts light that is traveling from a far away star/galaxy. That effect is like a train whistle approaching/receding or like a person riding in a car throwing something forward or backward. Of course the analogy fails slightly since light is always traveling the exact same speed, only its frequency (color) changes.

I was just trying to show the similarity between the 2 ideas. One is due to a traveling source and/or observer, the other is due to an expanding medium.

Re:Dakr Matter (1)

melgeroth (726004) | more than 10 years ago | (#9195692)

Yes, the red shift occurs because we detect a longer wavelength, since the object is moving away from us and so the wavelength appears to be 'streched' or longer (red is a low wavelength), just as the frequency appears to be lower. If the object had been moving towards us, the doppler effect would have shifted the wavelength up.

Re:Dakr Matter (2, Informative)

S3D (745318) | more than 10 years ago | (#9195470)

First, dont't mistake Dark matter [wikipedia.org] and Dark Energy [wikipedia.org] . They are completly different beast, and have only in common (is it true ? no one know) that both are in the number of biggest(together with quantum gravity) misteries of modern physics. Dark matter is a problem of mass distribution in tha galaxies. Dark Energy is a reason why universe expansion accelerating. From the formal point of view it's no more than a constant in the equations of General Relativity. And I think you are right, it's not "real" acceleration, it's expantion - the volume of the universes increase. Take a baloon and mark several points on it. Now blow baloon and distance between points increase. That is like the universe expansion. And it can be in some sence be faster then speed of light (that is the distance between points invrease faster than light travel from one to another) without contradiction to General Relayivity I think, becase points are not really moving - only distance between them increase (but I'm not a physisists, so I can be wrong here)

Re:Dakr Matter (1)

celeritas_2 (750289) | more than 10 years ago | (#9195527)

If you really want to know read Brian Greene's new book of which I have forgotten the name. The Universe expanding is like blowing up a baloon, put two dots anywhere on the baloon and as you blow it up they get farther apart, but not accelerating or moving vs the baloon. Space is the Baboon....er....baloon

Nibbles? (0, Offtopic)

leinhos (143965) | more than 10 years ago | (#9195306)

Does this mean that there's a little creature with a voracious appetite pooping in space?

Er, I mean Nibbler. Oh never mind... (2, Informative)

leinhos (143965) | more than 10 years ago | (#9195348)

Nibbler [gotfuturama.com]

perspective problem (5, Funny)

WormholeFiend (674934) | more than 10 years ago | (#9195316)

how do we know if something outside the universe isnt affecting it.

I'd like to think we live on an electron in orbit around the proton of a molecule as part of a giant coffee mug -- our universe is expanding due to some even bigger geek having just poured hot coffee in our universal mug.

It's "dark" cuz that's how this geek likes his coffee.

Re:perspective problem (2, Interesting)

Hussman32 (751772) | more than 10 years ago | (#9195408)

A guy I know that works at SLAC as an astrophysicist theorized it's not something that's expanding the universe, it's nothing. He was referring to a possible 'vacuum of space' that is pulling the matter and energy into the...uh, nothingness I guess.

Apparently the astrophysics bunch had evidence about the expanding universe already, I think this helps corroborate other evidence.

But I guess we'll never know for sure until it happens, so I guess we'll have to wait and see.

Re:perspective problem (3, Funny)

WormholeFiend (674934) | more than 10 years ago | (#9195440)

So your friend theorizes that we live in a universe about nothing?

Is he related to Jerry Seinfeld?

sweet!!! (1)

the_2nd_coming (444906) | more than 10 years ago | (#9195349)

with the existence of dark energy, we can now work at taping the dark energy or the Zero Point Force to get infinite energy!!!

Re:sweet!!! (0)

Anonymous Coward | more than 10 years ago | (#9195608)

with the existence of dark energy, we can now work at taping the dark energy or the Zero Point Force to get infinite energy!!!

That sounds like a lot of effort. Just bypass your meter.

Goofy gravity (4, Interesting)

ka9dgx (72702) | more than 10 years ago | (#9195350)

Dark Matter is a goofy, overly complicated theory to try to explain something obvious. Gravitons don't come from matter, gravitons, like any other particle... PUSH, they don't pull.

Gravitation is a shadowing effect. (Yes, all the formulae still work, except when you get out towards the edges of space)

--Mike--

Re:Goofy gravity (2, Interesting)

Betelgeuse (35904) | more than 10 years ago | (#9195437)

Wow. This makes MOND [umd.edu] sound like a mainstream theory! :-)

Re:Goofy gravity (1)

m1a1 (622864) | more than 10 years ago | (#9195583)

While it's easy to make fun of this particular theory it isn't so far fetched to think that perhaps gravity doesn't work exactly how we think it does. I think the combination or dark matter (on a local scale galaxies aren't behaving how we think they should based on their mass) and dark energy (on a universal scale the galaxies aren't behaving how we think they should based on mass) kind of hints more at an error in our theory than the existence of invisible particles nobody knows about. In fact, when I read papers about dark X I am often reminded of various "old school" scientific ideas such as ether or Ptolemic astronomy. I'm not saying GR is wrong, far from it. But I think it's pretty obvious that we don't have the whole story. Our theory is incomplete.

Re:Goofy gravity (0)

Anonymous Coward | more than 10 years ago | (#9195446)

Could you elaborate on that maybe? Give some links perhaps?

Re:Goofy gravity (2, Funny)

CodeMonkey4Hire (773870) | more than 10 years ago | (#9195528)

<Sarcasm>
So the Earth's gravitons are pushing at me, and mine at the Earth, so we repel? It must be all the gravitons from space and the atmosphere pushing me down against the Earth then.
</Sarcasm>

Re:Goofy gravity (2, Funny)

eclectro (227083) | more than 10 years ago | (#9195668)

So the Earth's gravitons are pushing at me, and mine at the Earth, so we repel? It must be all the gravitons from space and the atmosphere pushing me down against the Earth then.


This only works for however long the LSD lasts.

Re:Goofy gravity (1)

wwest4 (183559) | more than 10 years ago | (#9195591)

googly, googly....

this idea is based on the concept of "photon holes" in the EM field that travel backwards in time and impart a negative impulse on the body. photon holes are assumed to have just as much physical realness as photons (photon holes == gravitons).

it seems a lot more elegant than "dark matter" and it has the benefit of making more intuitive sense (if you're comfortable with flipping the time arrow back and forth).

Re:Goofy gravity (1)

wwest4 (183559) | more than 10 years ago | (#9195617)

are there any real physicists who see it this way, or just the quack i found on google?

Re:Goofy gravity (2, Insightful)

Decaff (42676) | more than 10 years ago | (#9195712)

If it sounds strange enough, you can probably bet there are real physicists who see it that way...

I hope there's enough. . . (2, Funny)

jafac (1449) | more than 10 years ago | (#9195354)

Because I've got a kickass deck of Pokemon cards that's centered around Dark Energy. . . that's right, I'm baaaad.

3000 Gil (1, Funny)

stephenisu (580105) | more than 10 years ago | (#9195365)

12 Dark Crystals, 3000 Gil. Send /tell to Aribaud /obscure reference?

FYI for all you Hubble nuts (0, Insightful)

Anonymous Coward | more than 10 years ago | (#9195380)

This telescope is doing the exact same type of science that hubble is. The only difference is there is not some irration emotional attachment to this telescope and there is a much better return on investment for dollars going forward.

Ptolemy's back! (5, Interesting)

ogma (755652) | more than 10 years ago | (#9195415)

Does anyone else think that the cutting edge of physics is starting to resemble Ptolemy's system of astronomy? With all this 'dark' energy, and 'dark' matter, it's beginning to look like a lot of hand-waving.

Increasingly complex adjustments [utk.edu] (e.g. epicycles) were made to Ptolemy's system to explain the observed motions of the heavenly bodies. Then along comes Copernicus and tells us that we've been looking at it inside out all along, things are simple after all, we just have to adjust our viewpoint.

I think physics is overdue another Copernicus.

Re:Ptolemy's back! (2, Insightful)

FlynnMP3 (33498) | more than 10 years ago | (#9195550)

While astronomy does need another Copernicus, the times are different today. Most everything cosmologists discuss is theory these days. Only after the mathamatical models provide sufficient backing data, experiements are performed. Namely because these experiements are so costly.

I do agree all this dark matter seems like hand waving. Part of that is a lack of understanding on my part. But to be fair, even the cosmologists don't even have a handle on what they are talking about.

Re:Ptolemy's back! (1, Insightful)

Anonymous Coward | more than 10 years ago | (#9195557)

I think physics is overdue another Copernicus.

Feel free to step up at any time. Certainly many of us in the physics community feel likewise. And there have been many crazy ideas. Unfortunately, the experimental data rules out almost everything proposed so far.

Mark Twain once remarked: "Everyone talks about the weather but no one ever does anything about it." The same could be said for cosmological theories. Many people complain about the current system, but no one ever offers anything better.

Re:Ptolemy's back! (1)

m1a1 (622864) | more than 10 years ago | (#9195602)

Holy Crap!

I just suggested this in another thread (before I had read yours). Yes, that's exactly what I think. Epicycles were the first the I thought of when I read about dark matter and dark energy.

Re:Ptolemy's back! (2, Informative)

Anonymous Coward | more than 10 years ago | (#9195633)

Epicycles was an attempt to provide a describle causative mechanism. Dark Matter, as I understand it, is merely a placeholder for an observed, but non-understood entity.

Everyone knows ... (0, Offtopic)

h4rdc0d3 (724980) | more than 10 years ago | (#9195416)

... that all Dark Matter comes from the feces of the Nibblonians [gotfuturama.com] . Each pound of which weights over ten thousand pounds. Therefore, if there is this much Dark Matter, Dark Energy must exist to cause the expansion of the universe.

I'm pretty sure I have that card... (1)

untwisted (779622) | more than 10 years ago | (#9195452)

Dark matter isn't anything new, I'm pretty sure I've had that magic card since like... Third edition or something. hehehe

Headline is an Exaggeration (4, Insightful)

m1a1 (622864) | more than 10 years ago | (#9195480)

The headline to this story is an exaggeration. Of course, you can't blame it on the author seeing as the headlines of the major news sources were exaggerations as well.

So what, we have more evidence the universe is expanding at an accelerating rate. WE ALREADY KNEW THAT! This is just another indication that it's happening. This doesn't "prove" the existence of dark energy. It's still entirely possible (and I would suggest probable) that we just don't know the entire story about gravity. Physicists have gotten gravity wrong before after all.

so if it is expanding what is it expanding into? (1, Interesting)

Anonymous Coward | more than 10 years ago | (#9195489)

i always hear about the expanding, but what exactly are we expanding into?

My general theory of exansion..... (1)

MrIrwin (761231) | more than 10 years ago | (#9195502)

"The new findings support the theory that the universe will expand forever, provided there is enough dark matter"

In fact my general theory states that any container will keep expanding as long as you keep stuffing enougth material into it.

Can I have my Nobel prize now please?

Dark Energy not Dark Matter (4, Interesting)

forand (530402) | more than 10 years ago | (#9195505)

The original poster has it wrong, more dark matter decreases the expansion of the universe as one would expect, dark energy does the opposite changing the state function of the universe and thus allowing it to expand. IAA astro-physicist

Disappointment (3, Funny)

carvalhao (774969) | more than 10 years ago | (#9195522)

What, no pictures of "dark matter"?! That I'd call an announcement!!

:)

assumption...assumption...assumption (2, Insightful)

Anonymous Coward | more than 10 years ago | (#9195571)

This proves nothing and provides no evidence. Read the report... everything it states about ratios and measurements involves assumptions. This isn't science. This is a bunch of people with too much time on their hands and not enough real information.

This isn't science.

unknown type of material, is POSTULATED to hold clusters together.

The observed values of the gas fraction depend on the ASSUMED distance to the cluster.

they are THOUGHT to represent a fair sample of the

ASSUMING that dark energy is responsible for the acceleration

The new Chandra results SUGGEST that the dark energy

Dark Energy was proven before (4, Funny)

RoderickMcDougall (661783) | more than 10 years ago | (#9195607)

That was proved to me years ago when I met my housemates girlfriend. She was positively festering with it. She radiated me with it so much of it that I now have a latent ability to detect dark energy within a 5m radius.

Big Rip vs. Black Holes (4, Interesting)

ConversantShogun (227587) | more than 10 years ago | (#9195618)

I've seen a few references to a theory of a final "big rip," in which everything (even atoms) are torn apart by the expansionistic force.

Would this apply to black holes, as well? If black holes aren't ripped apart, would they continue to provide areas of gravity strong enough that particles in the vicinity don't undergo the rip?

Welcome to Cosmology Update. (3, Funny)

zenmojodaddy (754377) | more than 10 years ago | (#9195626)

From the Micro$oft school of cosmology. Take something ( a cosmological model ) that barely works, find out there's a yet another problem with it, and patch it ( with blather about dark matter ) in the hope that it works. Then find out that by introducing the patch to fix one problem, you find another ( er... what exactly is dark matter? Anyone? Please? )

Hey, I rubbished Micro$oft and the whole of modern cosmology in one post. Cool.

Left over matter/energy from another dimmension (5, Interesting)

Anonymous Coward | more than 10 years ago | (#9195629)

There was some PBS special a little while back that talked about "string theory" of reality and the possibility that the "Big Bang" was actually a big "collision" between this and another dimmension. The "collision" or interaction between the two different dimmensions not only created tremendous energy but also left some material from the other dimmesion in this one, dark matter. That is why the stuff is invisible with no known origin but somehow detectable. Kind of like the Old Ones.

Ugh (2, Interesting)

bo0ork (698470) | more than 10 years ago | (#9195631)

The names chosen, Dark Matter and Dark Energy reminds me of the 'ether' that space were filled with. I have a feeling that the current theories will go the way of the ether...

talk about joke science... (-1, Flamebait)

KnacTheMife (779539) | more than 10 years ago | (#9195639)

The Chandra's Rectum Observatory has provided new evidence supporting the existence of dark energy, the force causing the acceleration of anal expansion. The new findings support the theory that the anus will expand forever, provided there is enough dark matter. CNN and Newsday are running the story, originally reported by ASSA. Chandra's site has some good images and information on the three peanut clusters studied.

Einstein (2, Funny)

JaffaKREE (766802) | more than 10 years ago | (#9195647)

Later, after astronomers found the universe to be expanding, Einstein called the cosmological constant his greatest blunder. But theorists have been taking a new look at it since 1998, when astronomers found evidence of a repulsive counterpart to gravity in studies of distant exploding stars called supernovae.

Even when he's making stuff up, he's still right... We just don't find out until 80 years later.

The relief (3, Funny)

AmoebafromSweden (112178) | more than 10 years ago | (#9195673)

This is great news!

>The new findings support the theory that the >universe will expand forever

I was afraid that the universe would stop expanding and start collapsing and that would kill us all!

Why not oscillation rather than expansion? (3, Insightful)

Chemisor (97276) | more than 10 years ago | (#9195697)

Why are they ignoring the obvious (at least to me) possiblity that the universe oscillates around some optimal size. Imagine the universe as a rubber ball. Squeeze the ball and let it go. Every particle inside will immediately start moving away from the others at an accelerated pace, continuing to accelerate until passing the rest boundary, when it will start slowing down. What's causing the expansion? How about the reduction of space curvature? Imagine space as a tablecloth (ok, so I'm knee deep in analogies :) on a table with a hole in the middle. Place a heavy pitcher in the middle and the tablecloth will be pulled through the hole, pulling its edges closer together. This is what happens around a star according to general relativity theory. Now, the star is constantly radiating energy and losing mass, so the space is constantly uncurving. Because it is uncurving, it is expanding. When all the stars burn out, space will start collapsing again as energy falls into black holes. Then the black holes coalesce and make the big bang singularity, which explodes for some reason and everything starts all over again.

dark energy and energy conservation (4, Interesting)

Maimun (631984) | more than 10 years ago | (#9195704)

several months ago I posted a question regarding dark energy
Speaking of dark energy, I wonder whether [suppose it exists indeed] dark energy does not break the law of conservation of energy. Once I attended a public talk by someont from Fermi Lab [sorry, cannot recall the name] who said that dark energy is a constant quantity [a very small number in standard units] per volume of space. So, given that the Universe is expanding and is being pushed more and more this way by the dark energy, the quantity of dark energy goes up and up, right? So, if it has indeed the meaning of energy, there is more and more energy in the Universe, contrary to the law of conservation...

Sadly, after the mention public talk only very few questions were allowed and I missed the opportunity to ask the expert in person.

It got moddep up as Interesting +1, but nobody answered. Maybe this time...
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