Potential signs of 'interacting' dark matter suggest it is not completely dark after all

April 14, 2015
Approximately real-color image from the Hubble Space Telescope, of galaxy cluster Abell 3827. The galaxy cluster is made of hundreds of yellowish galaxies. At its core, four giant galaxies are smashing into each other. As the topmost of the four galaxies fell in, it left its dark matter trailing behind. The dark matter is invisible in this image, but its position is revealed by tell-tale gravitational lensing of an unrelated spiral galaxy behind the cluster, whose distorted image is seen as a blue arc. Trailing dark matter is predicted by theories in which dark matter is not perfectly dark, but feels more of the fundamental forces than just gravity. Credit: Dr. Richard Massey (Durham University)

Astronomers believe they might have observed the first potential signs of dark matter interacting with a force other than gravity.

An international team of scientists, led by researchers at Durham University, UK, made the discovery using the Hubble Space Telescope and the European Southern Observatory's Very Large Telescope to view the simultaneous collision of four distant at the centre of a galaxy cluster 1.3 billion light years away from Earth.

Writing in the journal Monthly Notices of the Royal Astronomical Society today (Wednesday, April 15, 2015), the researchers said one clump appeared to be lagging behind the galaxy it surrounds.

They said the clump was currently offset from its galaxy by 5,000 light years (50,000 million million km) - a distance it would take NASA's Voyager spacecraft 90 million years to travel.

Such an offset is predicted during collisions if dark matter interacts, even very slightly, with forces other than gravity.

Computer simulations show that the extra friction from the collision would make the dark matter slow down, and eventually lag behind.

Scientists believe that all galaxies exist inside clumps of dark matter - called "dark" because it is thought to interact only with gravity, therefore making it invisible.

Nobody knows what dark matter is, but it is believed to make up about 85 per cent of the Universe's mass.

Approximately real-color image from the Hubble Space Telescope, of galaxy cluster Abell 3827. The galaxy cluster is made of hundreds of yellowish galaxies. At its core, four giant galaxies are smashing into each other. As the topmost of the four galaxies fell in, it left its dark matter trailing behind. The dark matter is invisible in this image, but its position is revealed by tell-tale gravitational lensing of an unrelated spiral galaxy behind the cluster, whose distorted image is seen as a blue arc. Trailing dark matter is predicted by theories in which dark matter is not perfectly dark, but feels more of the fundamental forces than just gravity. Credit: Dr. Richard Massey (Durham University)

Without the constraining effect of its extra gravity, galaxies like our Milky Way would fling themselves apart as they spin.

In the latest study, the researchers were able to "see" the dark matter clump because of the distorting effect its mass has on the light from background galaxies - a technique called gravitational lensing.

The researchers added that their finding potentially rules out the standard theory of Cold Dark Matter, where dark matter interacts only with gravity.

Lead author Dr Richard Massey, Royal Society Research Fellow, in Durham University's Institute for Computational Cosmology, said: "We used to think that dark matter sits around, minding its own business.

"But if it slowed down during this collision, this could be the first dynamical evidence that dark matter notices the world around it.

"Dark matter may not be completely 'dark' after all."

The researchers note that while they appear to have observed the offsetting of dark matter, more investigation will be needed into other potential effects that could also produce a lag between the dark matter and the galaxy it hosts. Similar observations of more galaxies and computer simulations of galaxy collisions are under way to confirm the interpretation.

Team member Professor Liliya Williams, of the University of Minnesota, said: "Our observation suggests that dark matter might be able to interact with more forces than just gravity.

"The parallel Universe going on around us has just got interesting. The dark sector could contain rich physics and potentially complex behaviour."

Last month (March 2015), Dr Massey and colleagues published observations showing that dark matter interacted very little during 72 collisions between galaxy clusters (each containing up to 1,000 galaxies).

Today's latest research concerns the motion of individual galaxies. Researchers say that the collision between these galaxies could have lasted longer than the collisions observed in the previous study - allowing even a small frictional force to build up over time.

Taken together, the two results bracket the behaviour of dark matter for the first time. Dark matter interacts more than this, but less than that. Dr Massey added: "We are finally homing in dark matter from above and below - squeezing our knowledge from two directions.

"Dark matter, we're coming for you."

Explore further: Galaxy clusters collide—dark matter still a mystery

More information: The behaviour of dark matter associated with 4 bright cluster galaxies in the 10kpc core of Abell 3827, Massey, R, et al, Monthly Notices of the Royal Astronomical Society, DOI: 10.1093/mnras/stv467

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verkle
Apr 14, 2015
This comment has been removed by a moderator.
Jim4321
3.4 / 5 (10) Apr 14, 2015
If they saw gravitational lensing offset from the visible matter -- then they have found something extraordinary. Now they said that "whatever they have observed" may have interact with some other force -- but they were too coy to say what other force. The only other long range force is electromagnetism. If the force (not too be named) is electromagnetic -- then dark matter should have an index of refraction and the speed of light should vary if it goes through dark matter. Could this be used to confirm or deny that whatever they have found interacts with electromagnetism?
dogbert
1.7 / 5 (22) Apr 14, 2015
"The parallel Universe going on around us has just got interesting. The dark sector could contain rich physics and potentially complex behaviour."


Parallel Universe? Why not? Fantasy universes to go with our fantasy matter.

Sometime in the future, we should return to using actual science ...
Vietvet
4.1 / 5 (22) Apr 14, 2015
@verkle

Like Noah's flood?
cantdrive85
1.6 / 5 (19) Apr 14, 2015
Without the constraining effect of its extra gravity, galaxies like our Milky Way would fling themselves apart as they spin.


This is only true if gravity, natures weakest force, is the only mover and player on cosmological scales. Fortunately, the Universe prefers to utilize all of the tools in it's bucket including electrical and magnetic forces.
Benni
1.6 / 5 (19) Apr 14, 2015
At the very core of this cluster is a huge giant Elliptical galaxy on the order of 50 times greater than the Milky Way. Close by you can observe several other large Ellipticals all larger than our MW. Because Only Elliptical galaxies have enough mass for sufficient gravity to be present for lensing, is it no wonder we see such a show of lensing with all those giant Ellipticals in the foreground.

Odd isn't it? How the PhysOrg writeup doesn't mention anything about those giant Ellipticals in the foreground? What's up with Massey that he never has any interest in discussing the fact that all his write-ups on DM has yet to mention even the slightest scintilla of the effects of the massive gravity fields created by the giant Ellipticals. You begin to get the impression he thinks the existence of the Ellipticals is because DM just sort of came along & formed the Ellipticals & the Ellipticals are simply a byproduct of the existence of DM.
big_hairy_jimbo
3.2 / 5 (5) Apr 14, 2015
If dark matter can lag behind like this, then surely there are clumps of DM just sat by themselves somewhere. Dark blobs maybe? Since DM is what holds galaxies together, then if the DM lags behind, surely the colliding galaxy would have its stars thrown everywhere, more so than expected if you didn't include the DM model. OR perhaps the Galaxy stripped of its DM ends up tugging back on the DM blob and they once again combine, perhaps even changing the whole shape of the galaxy itself. Maybe this process is what causes dwarf galaxies.
Yeah I know lots of maybes!!!!!
Benni
1.7 / 5 (17) Apr 14, 2015
Since DM is what holds galaxies together


Just so you know, 60-70% of the mass of the Universe is bound up in Elliptical galaxies. All the gravitational lensing observed occurs only with the presence of giant Ellipticals in the foreground, never with Spiral galaxies in the foreground, this is because Spirals are so deficient in gravity they are incapable of creating gravitational lensing. This is just a plain statement of fact, it doesn't matter that the Believers of Cosmic Fairy Dust don't like this little factoid, it still remains.

I'd be pleased if you'd show me a Spiral galaxy lensing an Elliptical.........ever see one of those pictures? Or maybe a Spiral lensing a Spiral? Never seen one of those have you? The reason is lack of gravity inherent within Spiral galaxies to create lensing. Massey however would like to have you believe Spirals must contain extraordinary gravity to keep the rotation rate from causing them to self destruct. So where also is the lensing?
Returners
2 / 5 (4) Apr 14, 2015
All gravitational matter would have to obey conservation of angular momentum, and therefore it interacts.
SnowballSolarSystem _SSS_
1 / 5 (6) Apr 14, 2015
Suppose DM were composed of zillions of gravitationally-bound (GB) giant molecular clouds (GMCs) composed of Bok globules (BGs). The GB state can internally absorb considerable angular momentum (AM), & since offset linear momentum (LM) is AM, the GB state can also absorb LM.

Back to reality in which GMCs are luminous, but what if GMCs are merely the visible 'excited state' of DM we'll call DM 'globule clusters', where the gaseous stellar metallicity of GMCs in their 'normal dark state' are 'snowed out into icy chondrules, leaving only molecular hydrogen and helium which don't absorb below the Lyman-alpha hydrogen line in UV, rendering gaseous (H2 + He) + icy chondrules essentially dark.

So DM globule clusters on steeply-inclined halo orbits shoot through the disk plane, whereas GMCs on shallow inclinations suffer sublimation from stellar radiation, rendering BGs and GMCs visible and succeptable to Jeans instability, since gaseous metallicity raises the 'sound crossing time'.
Shootist
5 / 5 (19) Apr 14, 2015
You would think that with all of the dark matter articles on PHYS.ORG scientists would have something more to back up their claims. So funny that something never observed receives so much attention. Maybe we can get back to talking about REAL topics.



Claims? claims for what? that something unseen appears to be causing more gravity to be present than can be accounted for by what IS seen?

I have never understood what the problem is that you people keep going on about.
docile
Apr 14, 2015
This comment has been removed by a moderator.
SnowballSolarSystem _SSS_
1 / 5 (4) Apr 14, 2015
If they saw gravitational lensing offset from the visible matter -- then they have found something extraordinary. Now they said that "whatever they have observed" may have interact with some other force -- but they were too coy to say what other force. The only other long range force is electromagnetism. If the force (not too be named) is electromagnetic -- then dark matter should have an index of refraction and the speed of light should vary if it goes through dark matter. Could this be used to confirm or deny that whatever they have found interacts with electromagnetism?


A gravitationally-bound state can absorb energy, linear and angular momentum internally, which is why galaxy mergers aren't elastic like hyperbolic-orbit close encounters between individual stars, so dark matter in a gravitationally-bound state could very well behave like it were experiencing an additional non-gravitational force.
liquidspacetime
1.4 / 5 (10) Apr 14, 2015
Dark matter is not a clump of stuff traveling with the matter. Matter does interact with dark matter.

Dark matter fills 'empty' space. Dark matter is displaced by matter.

The Milky Way moves through and displaces the dark matter.

The Milky Way's halo is the state of displacement of the dark matter.

The state of displacement of the dark matter is otherwise known as curved spacetime.

The Milky Way's halo *is* curved spacetime.
Skepticus_Rex
4.7 / 5 (15) Apr 14, 2015
...I'd be pleased if you'd show me a Spiral galaxy lensing an Elliptical.........ever see one of those pictures? Or maybe a Spiral lensing a Spiral? Never seen one of those have you? The reason is lack of gravity inherent within Spiral galaxies to create lensing....


Take a look at B1608+656. That is a large spiral with a large dust band (or possibly two galaxies colliding, both of which are lensing), that is lensing something behind it pretty extensively. It is within the range of normal disk/spiral galaxies.

Here is a picture of the galaxy and lensing:
http://www.spacet...408b.jpg
TheOrphan
1 / 5 (4) Apr 15, 2015
Yet another possible indication that DM doesn't exhibit the same G constant as larger atomic/sub atomic structures.
Returners
1.4 / 5 (11) Apr 15, 2015
Claims? claims for what? that something unseen appears to be causing more gravity to be present than can be accounted for by what IS seen?

I have never understood what the problem is that you people keep going on about.


Hypothesis. It could be a 5th force between ordinary matter, not observable on local scales.

Remember, each of the known forces interacts, in general, on a larger scale, but smaller energy level, than the previous force, Gravity being the weakest, but largest; First described, but last of the "Four" to be understood it seems...

If space-time is curved by mass due to Gravity, then the distance between objects in some dimensions is shorter than in others. Into "what" is space-time being curved? One of the other 4 dimensions, or is it a higher dimension? If it's a higher dimenstion, then forces existing in said dimension would be closer to the other object (M and m in gravity) and thereby have a stronger effect than initially calculated.
Returners
1 / 5 (13) Apr 15, 2015
Everything is closer together in the 5th dimension, and closer still in the 7th dimension, if these dimensions exist.

In the 5th dimension, the 2 galaxies might be half as far apart, therefore they experience 4 times as much attraction.

Viola, DM disappears and ordinary gravity in a higher dimension explains away the phenomenon without pixie dust or voodoo particles.

What am I saying?

Everything is made of pixie dust and voodoo particles...

"By FAITH God framed the WORLDS from things which do not appear(are not visible)."

If Dark Matter exists it is the strongest evidence ever of special creation. Atoms are invisible to the naked eye, and DM is invisible to everything, and the 5th dimension is invisible, and one way or another, the universe is made of the stuff.
Returners
1 / 5 (14) Apr 15, 2015
IMAGINE THAT.

The eternal God created the universe through faith. Not even forces, but the mere belief in himself. Cogito Ergo Sum... "I Think therefore I AM....Telll them I AM has sent you..."

Deep stuff....looks like God did Descartes work eons ahead of time. I think therefore I AM. God's name given to Moses was simply "I AM". I think therefore I AM.

So this eternal God probably gets bored being the only thing that exists, and decided to create universes capable of containing scale down versions of himself, such as ourselves, "I said ye are Gods," in His own image and likeness...

Then the humans refuse to believe this God exists even though the evidence is plain to see.
hillmeister
4.7 / 5 (3) Apr 15, 2015
Dark matter cant hide from the light for too long. ;)
reset
1.7 / 5 (12) Apr 15, 2015
You would think that with all of the dark matter articles on PHYS.ORG scientists would have something more to back up their claims. So funny that something never observed receives so much attention.


Claims? claims for what? that something unseen appears to be causing more gravity to be present than can be accounted for by what IS seen?

I have never understood what the problem is that you people keep going on about.


"Without the constraining effect of its extra gravity, galaxies like our Milky Way would fling themselves apart as they spin."

"They said the clump was currently offset from its galaxy by 5,000 light years (50,000 million million km) - a distance it would take NASA's Voyager spacecraft 90 million years to travel."

No mention of how the stars comprising the galaxy have reacted to having the gravity field which holds it together offset by 5000 years...but we can see the lensing!!!! Neat trick.


Torbjorn_Larsson_OM
5 / 5 (9) Apr 15, 2015
Interesting.

The problem I see is that the observation is just a 3.3 sigma observation [from the abstract figures]. Astronomers and particle physicists would like to see 5 sigma, to account for "look elsewhere" data fishing problems.

But if they can make a couple of these observations, and as they suggest exclude other possibilities, this result could go far.
Benni
1 / 5 (4) Apr 15, 2015
I'd be pleased if you'd show me a Spiral galaxy lensing an Elliptical.........ever see one of those pictures? Or maybe a Spiral lensing a Spiral? Never seen one of those have you? The reason is lack of gravity inherent within Spiral galaxies to create lensing.


Take a look at B1608+656. That is a large spiral with a large dust band (or possibly two galaxies colliding, both of which are lensing), that is lensing something behind it pretty extensively. It is within the range of normal disk/spiral galaxies


B1608+656 is not a Spiral galaxy as you misinterpret the picture, it is a galaxy cluster. Do you know what a "galaxy cluster" is? Well, this is exactly the same as the Abell under discussion in this article. The B1608+656 cluster is dominated by giant Ellipticals creating a lens for a quasar a couple billion light years distance behind it. It is the total gravitational field of all the galaxies combined which create this lens, not just a single galaxy.

antialias_physorg
5 / 5 (10) Apr 15, 2015
The problem I see is that the observation is just a 3.3 sigma observation

I don't think that's much of an issue as they are very careful in their wording (looking at the first sentence of article):
Astronomers believe they might have observed the first potential signs of dark matter interacting with a force other than gravity.


(Note that 3.3. sigma is already way better than the requirement for a 'definite discovery' in some other scientific areas. It's not the standard for astrophysics, but certainly a significant enough anomaly in the data that merits closer scrutiny on this, and similar, objects)

Gotta start unravelling these mysteries somewhere.
Skepticus_Rex
5 / 5 (10) Apr 15, 2015
B1608+656 is not a Spiral galaxy as you misinterpret the picture, it is a galaxy cluster. Do you know what a "galaxy cluster" is? Well, this is exactly the same as the Abell under discussion in this article....


I know exactly what a galaxy cluster is. B1608+656 is a cluster but at the center of it is the primary lensing galaxy I wanted people to look at. The primary lensing galaxy has a dust lane and recently has been classified as a disk/spiral galaxy (with a possible galaxy collision). You should update your information.
Torbjorn_Larsson_OM
5 / 5 (12) Apr 15, 2015
@Jim: "Now they said that "whatever they have observed" may have interact with some other force -- but they were too coy to say what other force. The only other long range force is electromagnetism."

Yes, but that is excluded for dark matter, hence its name. It would be much stronger, cf baryonic matter, if it was directly affecting these fields.

They are coy because they can't say much about it except that it is new, exotic, physics: "The dark sector could contain rich physics".

For example, if dark matter is supersymmetric (SS) particles, they could have a supersymmetric photon analog that the massive SS fields couple to.

But I don't think that would be their primary suspect. Rather weakly interacting SS particles, WIMPS, could be enough of an interaction boost in a collisional regime. That is all they have measured so far I think, the collision cross section between DM and DM. (But I haven't read the paper.)
Torbjorn_Larsson_OM
5 / 5 (11) Apr 15, 2015
@Benni: "B1608+656 is not a Spiral galaxy as you misinterpret the picture, it is a galaxy cluster."

No, after quick googling it appears to me it doesn't seem to be. [Sorry about the double qualification!]

Astronomers can model it as two galaxies under lensing, and that works well. [ http://arxiv.org/...73v2.pdf ]

Hence "a large spiral with a large dust band (or possibly two galaxies colliding, both of which are lensing)" is a rather good description. (I don't know if the galaxies are colliding instead of close in a lensing 3D sense, but maybe one can tell after reading that paper with possibly some number crunching needed, yikes. A naive guess would be that a collision, earlier or later, would be likely.)
Benni
1.4 / 5 (9) Apr 15, 2015
B1608+656 is not a Spiral galaxy as you misinterpret the picture, it is a galaxy cluster. Do you know what a "galaxy cluster" is? Well, this is exactly the same as the Abell under discussion in this article.


I know exactly what a galaxy cluster is. B1608+656 is a cluster but at the center of it is the primary lensing galaxy I wanted people to look at. The primary lensing galaxy has a dust lane and recently has been classified as a disk/spiral galaxy (with a possible galaxy collision). You should update your information.
..at least you got the galaxy collision part of it right, everything else is an amorphous blending DOMINATED by Ellipticals. You're just trying to wedge Spirals into this lens because you want to advance a narrative for DM to be the sole driver for the lensing occurring here.

By the way Ellipticals do not need the DM narrative to explain their inherent gravity, the Newtonian Inverse Square Law works just fine, just in case you didn't know this.
Torbjorn_Larsson_OM
5 / 5 (10) Apr 15, 2015
@aa: "I don't think that's much of an issue as they are very careful".

Picky. I admit I wasn't very careful in my wording, so I can't say it is obvious I was referring to the physics, not the paper. But I didn't give anyone a reason to exclude that option either.

"3.3. sigma is already way better than the requirement for a 'definite discovery' in some other scientific areas."

To play "picky back":

Yes. If they don't have problems with data fishing it works well, the 3 sigma quality is ~1/340 mistakes. In medicine they have to accept low p values and low effect sizes meanwhile they can look at 100s of 1000s of active substances or potential disease carrying single base pair changes in genomes nowadays (aka data fishing), and as a result ... they have to do repeats. =D

"Gotta start ... somewhere."

Agreed.
Torbjorn_Larsson_OM
4.9 / 5 (13) Apr 15, 2015
@Benni: "Ellipticals do not need the DM narrative to explain their inherent gravity".

First, this is science and not pomo bullshit. So there are no 'narratives' here. DM is a theory - a successful such.

Second, here you go making claims that it takes 10 s to google up are erroneous.

"Some elliptical galaxies show evidence for dark matter via strong gravitational lensing,[33] X-ray evidence reveals the presence of extended atmospheres of hot gas that fill the dark haloes of isolated ellipticals and whose hydrostatic support provides evidence for dark matter. Other ellipticals have low velocities in their outskirts (tracked for example by planetary nebulae) and were interpreted as not having dark matter haloes.[10]

[tbctd]
antialias_physorg
5 / 5 (11) Apr 15, 2015
and as a result ... they have to do repeats

Medical research (which I was professionally involved in) doesn't have much of an option. You would need humongous studies to get to 5 sigma.
And since you're dealing with real people you're always dealing with multivariate studies. You need to correct for age discrepancies, gender discrepancies, in some cases for medical history discrepancies (sometimes even socio-economic discrepancies or population genetic variations if your study draws from patient pools in different parts of the globe) etc., etc.

Getting to a ~1/20 mistake value is the best you can hope for under these conditions (and for that we're already talking in excess of 100m EUR per drug that actually makes it to market through all the test phases..and only roughly 1 in 100 drugs get that far)
Torbjorn_Larsson_OM
5 / 5 (10) Apr 15, 2015
[ctd]

However, simulations of disk-galaxy mergers indicate that stars were torn by tidal forces from their original galaxies during the first close passage and put on outgoing trajectories, explaining the low velocities even with a DM halo.[34] More research is needed to clarify this situation."

[ http://en.wikiped...k_matter ]

"The general conclusion, taking into account all these studies, could be, in summary, that dark matter amounts comparable to visible matter could be present in the visible part of the galaxy, and that larger dark matter amounts, probably as large as in spirals, are present in a halo surrounding the galaxy, but that, in any case, the evidence of dark matter in ellipticals is less than in the case of spirals. Even the complete absence of dark matter cannot be easily ruled out."

[ http://ned.ipac.c...e11.html ]

[tbctd]
Torbjorn_Larsson_OM
4.9 / 5 (9) Apr 15, 2015
[ctd]

So it is needed in some cases, for example if you look at gas and not only stars. And it can't be ruled out even in cases were it is hard to see, due to dynamic effects that naive rotation curves do not account for.
Skepticus_Rex
4.9 / 5 (11) Apr 15, 2015
..at least you got the galaxy collision part of it right, everything else is an amorphous blending DOMINATED by Ellipticals. You're just trying to wedge Spirals into this lens because you want to advance a narrative for DM to be the sole driver for the lensing occurring here.


_I_ don't want to advance anything. I'm getting my information from the Astronomers who have been studying this region of space. A recent paper I read stated that the primary lensing galaxy is now classified as a disk/spiral galaxy. As I said, you need to update.
nswanberg
1 / 5 (3) Apr 15, 2015
Existics.
IMP-9
5 / 5 (11) Apr 15, 2015
The reason is lack of gravity inherent within Spiral galaxies to create lensing.


http://adsabs.har...17L..39J
http://adsabs.har...11..389J
http://adsabs.har...90..691H
http://adsabs.har...74L..25J

It is also the greatest hypocrisy to bang on about ellipticals, ignoring the cluster and then object when someone does exactly the same. It may be in a cluster but that doesn't mean it isn't doing the lensing. If it separates the two images the chances are good.

I had more sources but this crappy site deleted them.
Benni
1 / 5 (9) Apr 15, 2015
..at least you got the galaxy collision part of it right, everything else is an amorphous blending DOMINATED by Ellipticals. You're just trying to wedge Spirals into this lens because you want to advance a narrative for DM to be the sole driver for the lensing occurring here.


_I_ don't want to advance anything. I'm getting my information from the Astronomers who have been studying this region of space. A recent paper I read stated that the primary lensing galaxy is now classified as a disk/spiral galaxy. As I said, you need to update.


Sure, you managed to find one cluster where a Spiral happened to get caught up in a collision squeeze between several Ellipticals & voila, you dream up a narrative that the lens woudn't even exist if it were not for the presence of that one lone spiral which in the process of the collision with other nearby galaxies is morphing into an Elliptical. You need to update your knowledge on Einstein Field Equations for gravity.
Skepticus_Rex
5 / 5 (8) Apr 15, 2015
Sure, you managed to find one cluster where a Spiral happened to get caught up in a collision squeeze between several Ellipticals & voila, you dream up a narrative that the lens woudn't even exist....


You obviously have misread what I stated. I said nothing of the kind. What I did state was that the spiral in the cluster is the primary lensing galaxy, and that isn't my claim. It is the claim of the astronomers studying the region. Time for you to update.
yyz
5 / 5 (13) Apr 15, 2015
Benni,

You've already been given several examples of gravitational lensing by spiral galaxies:

http://fr.arxiv.o...101.1622

http://fr.arxiv.o...01.01638

http://fr.arxiv.o.../0611330

I don't understand why you persist in denying the FACT that spiral galaxies can gravitationally lense other galaxies, even when shown empirical evidence. Can you give even cite one paper that declares gravitational lensing by spiral/disk galaxies impossible?

Precisely why is gravitational lensing by spiral galaxies impossible?

Sez who?
Uncle Ira
4.1 / 5 (9) Apr 15, 2015
Sez who?


Sez Bennie-Skippy when he gets tired of saying Differential Equations and semi-circular-half-spherical-universes.
Benni
1 / 5 (10) Apr 15, 2015


(Un) holy DM......so many of you who are missing the whole thing about Gravitational Lensing in this article. There is nothing in the entirety of the Universe that cannot & does not create "lensing effects". Einstein calculated it in his GR when he calculated the lensing effects of starlight passing the disk of the Sun & a few years later it was proven.

It is not necessary for the mass of an entire galaxy to be present to create lensing, but with the two clusters under discussion here what is obvious are the Einstein Rings surrounding the entire clusters which are dominated by giant Ellipticals. It is the total mass of the cluster that is causing the Einstein Rings. But If I'm to believe Massey's understudy here, he would have me believe that a miniscule spiral/disk has gravitationally lensd these clusters to the point of creating the Einstein Rings.

Hey Rex, update your math, I can do all the the Differential Equations in Einstein's GR.

yyz
5 / 5 (11) Apr 15, 2015
"There is nothing in the entirety of the Universe that cannot & does not create "lensing effects"."

Benni, in this very thread you stated:

"Spirals are so deficient in gravity they are incapable of creating gravitational lensing. This is just a plain statement of fact..."

So which is it? First you say spirals cannot produce gravitational lensing, now you say any mass can create gravitational lensing. You contradict yourself within the same thread. When your erroneous assumption wrt spiral galaxies and gravitational lensing is pointed out by Skepticus Rex, Torbjorn Larsson and myself, you double down on the denial. I first pointed out to you these examples of lensing by spiral galaxies several weeks ago:

http://phys.org/n...firstCmt

Yet you continue to repeat the same (unsupported) statements and declare them facts. It seems to be you, Benni, that has "dreamed up a narrative" and then fails to offer supporting evidence.
Skepticus_Rex
5 / 5 (9) Apr 15, 2015

Hey Rex, update your math, I can do all the the Differential Equations in Einstein's GR.



And, yet the primary lensing galaxy in that cluster still is classified as a disk/spiral galaxy. Time for you to update.
Moebius
1.8 / 5 (5) Apr 16, 2015
This article and others claim that the dark matter cloud is trailing its associated galaxy. If the dark matter cloud is trailing its galaxy wouldn't that negate its whole claim to existence? How can dark matter explain the formation and movement of a galaxy if it's trailing it? In order to explain the speed of movement of a galaxy's arms and its cohesion I would expect that the dark matter cloud would need to be centered on the galaxy.

More evidence to me that it doesn't exist and there's another explanation to the effect.
dogbert
1 / 5 (1) Apr 16, 2015
How can dark matter explain the formation and movement of a galaxy if it's trailing it?


More to the point, if dark matter is necessary for a galaxy to hold on to its stars and gas, and you remove the dark matter, shouldn't the galaxy simply disintegrate?
antialias_physorg
5 / 5 (9) Apr 16, 2015
How can dark matter explain the formation and movement of a galaxy if it's trailing it?

Because it's not trailing. From the article:
They said the clump was currently offset from its galaxy by 5,000 light years

(For comparison: A galaxy like our own has a diameter of 100k-120k light years.) If the galaxy is comparable by size (all I could find is that it is 'one of four giuant galaxies) then that would be an offset of less than 10% towards the edge. If it's offset in the axial direction then galaxies liek our own are still 20k light years thick. So in any case it would still be not significantly behind the galaxy it's associated with.

The galaxy is a part of the Abell 3827 group which seems to have had a rather turbulent recent interaction history
http://en.wikiped...SO_146-5
liquidspacetime
1.3 / 5 (8) Apr 16, 2015
How can dark matter explain the formation and movement of a galaxy if it's trailing it?


The two main misconceptions about dark matter are:
1) It travels along with the matter
2) It doesn't interact with matter

Dark matter fills 'empty' space. Dark matter is displaced by matter.

The analogy is a submarine moving through and displacing the water. The state of displacement of the water appears to be trailing the submarine. It appears to be trailing the submarine because the submarine is moving through and displacing it.

The Milky Way's dark matter halo appears to be trailing the Milky Way because the Milky Way is moving through and displacing it; analogous to a submarine moving through and displacing the water.
antialias_physorg
5 / 5 (8) Apr 16, 2015
Dark matter fills 'empty' space.

What does that even mean?

Dark matter is displaced by matter.

No. That would be a VERY strong type of interaction and that would be easily observable in places where galaxies are currently in the process of colliding.
liquidspacetime
1.1 / 5 (7) Apr 16, 2015

What does that even mean?


Dark matter is now understood to fill what would otherwise be considered to be empty space.

'Cosmologists at Penn Weigh Cosmic Filaments and Voids'
http://www.upenn....nd-voids

"A long standing mystery on where the missing dark matter is has been solved by the research. There is no empty space in the universe. The intergalactic space is filled with dark matter."

No. That would be a VERY strong type of interaction and that would be easily observable in places where galaxies are currently in the process of colliding.


How does matter curve spacetime if it doesn't interact with it strongly?
antialias_physorg
5 / 5 (8) Apr 16, 2015
How does matter curve spacetime if it doesn't interact with it?

You said dark matter would displace matter. That's a very strong interaction (which means we would see transfer of impulse...which in turn would be very visible as galactic matter being thrown way off course and shockwaves when encountering a region of dark matter (with the ancillary heating).

I.e. we should see galaxies heating up a lot BEFORE the main bodies of matter hit one another. That is not observed
liquidspacetime
1.1 / 5 (8) Apr 16, 2015
The dark matter is, or behaves similar to, a supersolid. Objects do not generate heat when they interact with it.

Matter curving spacetime is a strong interaction, correct? Why doesn't spacetime have the same constraint that it should heat up as it is curved by matter? Or do you just accept spacetime is curved by matter because it's only the mathematical concept of a 'field'?

Somehow, you just accept that spacetime is curved by matter. However, since dark matter physically occupies three dimensional space and is displaced by matter you place all sorts of constraints on dark matter being displaced by matter that you don't for spacetime being curved by matter.

Curved spacetime *is* the state of displacement of the dark matter.

The Milky Way's halo *is* curved spacetime.

Spacetime has mass.
liquidspacetime
1 / 5 (9) Apr 16, 2015
Label it whatever you want, 'empty' space has mass which is physically displaced by the particles of matter which exist in it and move through.

I prefer the term aether.

Aether has mass which physically occupies three dimensional space and is physically displaced by the particles of matter which exist in it and move through it.

What ripples when galaxy clusters collide is what waves in a double slit experiment; the aether.

Einstein's gravitational wave is de Broglie's wave of wave-particle duality; both are waves in the aether.

Aether displaced by matter relates general relativity and quantum mechanics.
antialias_physorg
4.6 / 5 (11) Apr 17, 2015
Label it whatever you want, 'empty' space has mass

Weird how every experiment conducted in that respect ever conducted shows actual data that comes to the opposite conclusion, isn't it?

But don't let reality stand in the way of your beliefs. So few religious people do.
liquidspacetime
1 / 5 (6) Apr 17, 2015
The Milchelson-Morley experiment looked for an absolutely stationary space the Earth moves through. The aether is not an absolutely stationary space.

The ether is displaced by the particles of matter which exist in it and move through it.

In the following two articles the aether is what waves in a double slit experiment.

'From the Newton's laws to motions of the fluid and superfluid vacuum: vortex tubes, rings, and others'
http://arxiv.org/abs/1403.3900

"This medium, called also the aether, has mass and is populated by the particles of matter which exist in it and move through it" ...

... and displace it.

'EPR program: a local interpretation of QM'
http://arxiv.org/abs/1412.5612

"Wave particle duality is described as the compound system of point particle plus accompanying wave (in the æther)."
Benni
2 / 5 (4) Apr 17, 2015
The Milchelson-Morley experiment looked for an absolutely stationary space the Earth moves through. The aether is not an absolutely stationary space.

The ether is displaced by the particles of matter which exist in it and move through it.

In the following two articles the aether is what waves in a double slit experiment.

'From the Newton's laws to motions of the fluid and superfluid vacuum: vortex tubes, rings, and others'
http://arxiv.org/abs/1403.3900

"Wave particle duality is described as the compound system of point particle plus accompanying wave (in the æther)."


Liquid, you & Massey are twins, right?
liquidspacetime
1 / 5 (8) Apr 17, 2015
Dark matter is now understood to fill what would otherwise be considered to be empty space.

'Cosmologists at Penn Weigh Cosmic Filaments and Voids'
http://www.upenn....nd-voids

"Dark matter ... permeate[s] all the way to the center of the voids."

'No Empty Space in the Universe --Dark Matter Discovered to Fill Intergalactic Space'
http://www.dailyg...ce-.html

"A long standing mystery on where the missing dark matter is has been solved by the research. There is no empty space in the universe. The intergalactic space is filled with dark matter."

Dark matter which fills 'empty' space is otherwise known as the aether. Aether has mass, physically occupies space and is physically displaced by the particles of matter which exist in it and move through it. Including 'particles' as large as galaxies and galaxy clusters.
liquidspacetime
1 / 5 (7) Apr 17, 2015
Another way to think about it: Spacetime has mass

Spacetime with mass = Dark matter

Matter curves spacetime

Matter displaces dark matter

Curved spacetime = Displaced dark matter
Steve 200mph Cruiz
5 / 5 (3) Apr 17, 2015
Friction?
Does that mean we should expect a particle of dark matter to have a spin 1? There was that other article a while back finding anomalous x rays that could be from rare decays of dark matter. Getting closer, maybe we can expect the LHC.
Also if dark matter is made of multiple particles, if only some of them experience friction, it seems like they could of been separated out in this system.
liquidspacetime
1 / 5 (6) Apr 17, 2015
Not friction. The dark matter is, or behaves similar to, a supersolid. Think of two boats moving through and displacing a supersolid. If they pass by each other closely their bow waves interact. This is what is being observed with the galaxy clusters. The galaxy clusters are moving through and displacing the dark matter. What they are observing is the dark matter displaced by each of the galaxy clusters interacting, analogous to the bow waves of two boats which pass by each other closely.
Steve 200mph Cruiz
5 / 5 (6) Apr 17, 2015
Liquidspace,
The article explicitly said friction, and I was listening to the head astrophysicist of this project on NPR today and he said it was probably friction too. I also don't think you know what a supersolid solid is.
liquidspacetime
1 / 5 (6) Apr 18, 2015
They also think dark matter is a clump of stuff traveling along with the matter which is incorrect

Curved spacetime *is* displaced dark matter.
Moebius
2 / 5 (1) Apr 18, 2015
Any offset from direct center of the galaxy of the center of mass of the associated cloud of dark matter that is supposedly responsible for the large scale structure of that galaxy would introduce some form of asymmetry to the shape of that galaxy depending on where the offset is.

I would expect an offset above the axis to create a cup shaped symmetrical galaxy. I would expect any off axis offset to result in asymmetry.
liquidspacetime
1 / 5 (5) Apr 18, 2015
'The Milky Way's dark matter halo appears to be lopsided'
http://arxiv.org/abs/0903.3802

"the emerging picture of the dark matter halo of the Milky Way is dominantly lopsided in nature."

The Milky Way's halo is not a clump of dark matter traveling along with the Milky Way. The Milky Way's halo is lopsided due to the matter in the Milky Way moving through and displacing the dark matter.

'Offset between dark matter and ordinary matter: evidence from a sample of 38 lensing clusters of galaxies'
http://arxiv.org/abs/1004.1475

"Our data strongly support the idea that the gravitational potential in clusters is mainly due to a non-baryonic fluid, and any exotic field in gravitational theory must resemble that of CDM fields very closely."

The offset is due to the galaxy clusters moving through and displacing the dark matter.
TheGhostofOtto1923
3.3 / 5 (7) Apr 19, 2015
Dark matter is fictional as the the curved space. As usually the real world is more simple than that described by theories of abstractionist. Unfortunately selfishness and vanity which are reflection of stupidity fail this world
Indeed, it is much simpler than the concept of one god composed of 3 separate parts, or is it 3 entities making up one whole god? And to boot, one of the 3 is the son of one of the others. And then there is the idea that this magnificent assemblage has a mother.

Many centuries of heated discussion and much bloodshed has gone into resolving this simple issue. Perhaps it is time to subject it to the scientific method?
TheGhostofOtto1923
3.3 / 5 (7) Apr 19, 2015
large cosmic structures like galaxies are well aware of their choreography, why some scientists to spend their time and money of taxpayers with imaginary phenomena that only must compensate their lack of understanding for the world in which they live? The answers are in the properties and structure of cosmic vacuum
Yes prayer is lots cheaper and doesn't require major facilities and hardware. Unless you're catholic that is. And gens of Christian Scientists swear by it. They know that if it doesn't work then they only need to pray harder next time.
Benni
1 / 5 (5) Apr 19, 2015
Hey Rex, update your math, I can do all the the Differential Equations in Einstein's GR.


And, yet the primary lensing galaxy in that cluster still is classified as a disk/spiral galaxy. Time for you to update.


Nope, you need to get your proficiency in studies of astro-physics updated because it is an observational fact that at the heart of every galactic cluster are giant Ellipticals.

Our MW is located within a galactic cluster called the Virgo Cluster & the galaxy that is at the center of our cluster is what? Of course you wouldn't know that because you haven't gotten that update yet from Massey....so I guess I need to be the one to tell you that it is a giant Elliptical estimated to be 50-100 times the size of the MW .

So now you know why certain galactic clusters cause 99.9999999999% of all the gravitational lensing in the universe, it's simply because only the giant Ellipticals within those clusthave enough inherent gravity to do the job.
Skepticus_Rex
5 / 5 (5) Apr 19, 2015
Benni,

Nope. And, yet, the galaxy at the center of the cluster is the disk/spiral galaxy, which also is identified as the primary lensing galaxy. And the number of those who are in agreement is growing. Time to update.
Benni
1 / 5 (5) Apr 19, 2015
Benni,
Nope. And, yet, the galaxy at the center of the cluster is the disk/spiral galaxy, which also is identified as the primary lensing galaxy. And the number of those who are in agreement is growing. Time to update.


So, you're still groping around with the Funny Farm Science crowd that populate the Commentary of this website who agree with you. It remains that you are totally clueless about what causes 99.9999999999999999999% of all gravitational lenses ever observed anywhere in the Universe. I guess I should conclude as well that you have never seen a Differential Equation in Einstein's GR that you could solve in addition to having no clue as to what Elliptical/Spheroid Galaxies look like no matter how clear the picture that is shown above.

I understand your need to wedge a puny Spiral into this mix, you need a stage to present your case that the gravity of Spirals exceed the gravity of Ellipticals & you think you've found it in the Rotation Rates of Spirals.
rufusgwarren
1 / 5 (1) Apr 19, 2015
The problem is identification. Listen to Joe Sample, "Hippies on the Block". The beat is a jazz particle.
rufusgwarren
1 / 5 (1) Apr 19, 2015
Or Shearing, "Out of this World".
rufusgwarren
1 / 5 (1) Apr 19, 2015
These jazzy particles are very elusive and may be called dark. You can only detect them with a high fidelity system. However, when one breaks up protons they appear and disappear; but, the trail can be detected with tools provided by James C. Maxwell. The wave front produced must only move at one speed. Forget about velocity and logical mathematics. Logic and proper math must be discarded in order to maintain the speed of the wave-front as a constant, even though the jazz particle appears to change. Vector addition does not apply; however, the music is great. But, the dichotomy produces noise. i.e. missing the jazz particle. Hence, the reason they are dark!
rufusgwarren
1 / 5 (1) Apr 19, 2015
Forget about the problematic event rates due to your relative motion, for like it is stated, vector addition does not apply; thus events must be as they appear. Only an idiot would suggest anything such as the logic or the math that creates flowers or balls of plasma. Meaning, no one can make sense from what is observed since it defies logical mathematics with the invention of a tensor that is irreconcilable mathematically; therefore, proof of dark matter.
Skepticus_Rex
5 / 5 (3) Apr 19, 2015
So, you're still groping around with the Funny Farm Science crowd that populate the Commentary of this website who agree with you. It remains that you are totally clueless about what causes 99.9999999999999999999% of all gravitational lenses ever observed anywhere in the Universe. I guess I should conclude as well that you have never seen a Differential Equation in Einstein's GR that you could solve in addition to having no clue as to what Elliptical/Spheroid Galaxies look like no matter how clear the picture that is shown above.

I understand your need to wedge a puny Spiral into this mix, you need a stage to present your case that the gravity of Spirals exceed the gravity of Ellipticals & you think you've found it in the Rotation Rates of Spirals.


You don't know very much about the dynamics here, do you? We do not agree on everything here on the site. We've had our disagreements but with what I see with the evidence, I have to go with that. It's a disk/spiral. Deal w/ it.
someone11235813
1 / 5 (2) Apr 20, 2015
So funny that something never observed receives so much attention.


Like curved space for example?
Benni
1 / 5 (4) Apr 20, 2015
You don't know very much about the dynamics here, do you? We do not agree on everything here on the site. We've had our disagreements but with what I see with the evidence, I have to go with that. It's a disk/spiral. Deal w/ it


I dealt with it back in the days when I took 5 Calculus courses & a plethora of courses in Chemistry, Electricity & Magnetism, Physics, Nuclear Physics, Thermodynamics & more. Your problem is proving to someone of my background why you are a competent purveyor of the subject matter in question. I seriously doubt you would recognize an Einstein Field Equation if someone wrote it down on a piece of paper & placed in front of your eyeballs & asked you if you recognized what you're looking at.

Here you are, someone claiming to know EVERYTHING there is to know about something that has never been proven to exist........that's an awfully lot to know about NOTHING.
Skepticus_Rex
5 / 5 (4) Apr 20, 2015
No, Benni, you actually are living in denial. You haven't really dealt with anything but are trying to stick with older ideas that are fast becoming out of date as a result of more recent research and observation. The disk/spiral galaxy is now known as the primary lensing galaxy in that group. Deal with it and get over it if you can. Or, better yet, publish an adequate refutation in a reputable scientific journal. Until then you are blowing hot air about nothing and bragging about your putative accomplishments that appear to mean little to nothing in light of this ongoing discussion.
Benni
1 / 5 (4) Apr 20, 2015
No, Benni, you actually are living in denial. You haven't really dealt with anything but are trying to stick with older ideas that are fast becoming out of date as a result of more recent research and observation. The disk/spiral galaxy is now known as the primary lensing galaxy in that group. Deal with it and get over it if you can. Or, better yet, publish an adequate refutation in a reputable scientific journal. Until then you are blowing hot air about nothing and bragging about your putative accomplishments that appear to mean little to nothing in light of this ongoing discussion.


.........quite a mouthful for someone who has never seen a Differential Equation in Einstein's GR that you could recognize much less solve. Why does it never dawn on those of you in the Funny Farm Science crowd that "adequate refutation" for the existence of something never proven to exist is an impossible feat, how does that math work? Maybe you have a Differential Equation for it?
Skepticus_Rex
5 / 5 (3) Apr 20, 2015
Benni,

How do you know what I have or have not seen? And, you really think that differential equations solve everything? If that is what you really think you still have a lot to learn about them and what they can and cannot do. You have shown your slip. Now, cover up a bit and get to updating. The disk/spiral galaxy now is identified as the primary lensing galaxy in the group. Get over it, if you can. But, that is the nature of science. It is always updating. Try not to get left too far behind.
murray_crawford85
3 / 5 (2) Apr 20, 2015
IMAGINE THAT.

The eternal God created the universe through faith. Not even forces, but the mere belief in himself. Cogito Ergo Sum... "I Think therefore I AM....Telll them I AM has sent you..."

Deep stuff....looks like God did Descartes work eons ahead of time. I think therefore I AM. God's name given to Moses was simply "I AM". I think therefore I AM.

So this eternal God probably gets bored being the only thing that exists, and decided to create universes capable of containing scale down versions of himself, such as ourselves, "I said ye are Gods," in His own image and likeness...

Then the humans refuse to believe this God exists even though the evidence is plain to see.


Ummmm..... What??
MRBlizzard
1 / 5 (1) Apr 20, 2015
"... Now they said that "whatever they have observed" may have interact with some other force -- but they were too coy to say what other force. The only other long range force is electromagnetism. ..."

The previous article

http://phys.org/n...rse.html

had a 17 minute movie showing the average motions of galaxies in the local universe. besides the force that creates voids of galaxies, there are apparently flows of galaxies representing dipole forces.

This appears to be new physics, both in the article cited and in this article.

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