Where is Dark Matter ?

[RawThinkTank]

Dark matter is everywhere. It is acting on U right now. Unfortunately no one can be told “What is Dark Matter”. No no its not the Matrix, its something unlike it, becuase Even if U r told what it is , U wont understand. Your specie has not yet evolved to understand it. It’s a matter of human comprehendebility. Can U guess what it is, Can U imagine how deep the rabbit hole goes ?

[James R]

It could be weakly-interacting massive particles (WIMPs) such as neutrinos. Or maybe it is massive, compact halo objects (MACHOs), although I think that idea may be on its last legs (not sure though).

I don't think it's a matter of comprehensibility. I think it's a matter of coming up with a good explanation.

[mathman]

Neutrinos are part of it, but can't be all, since the galaxies wouldn't have formed. In any case neutrinos can't be WIMPS (they are not massive). Other dark matter candidates include axions and neutralinos, whatever they are.

To further complicate the story, most of the universe is dark energy, which is even less understood.

[Avatar]

I just had a wild idea at the top of my head
--can't it be some kind of a "quantum gravity" from other universes that "bump" into our timespace thus making the illusion that there is hidden matter when in reality it's outside our universe
can it be so in theory if we assume that multiverse exists?

[Boris2]

http://www.monmouth.com/~snaef/STAR/PROGRAMS/dkmatter/rap_frame.html

worth reading.

:-)

[caffeine_fubar]

Dark Matter is a thing that our minds could possibly not comprehend... think of a new form of matter.... not gas, not liquid, not solid, not energy, not anything that we know of. Thats what i think it is.

Next issue: RawThinkTank, you act as though you are not human in your post.

Next issue: This is my 70th post!

[James R]

mathman:

Neutrinos do have very small masses.

[mathman]

I agree, WIMP stands for weakly interactive MASSIVE particle. Neutrinos have very tiny masses, they are not massive.

[James R]

Ah, sorry, there's been a misunderstanding. When a physicist says "massive", they mean only "having mass", not "humungous", as in the common usage of the word "massive". Thus, neutrinos are "massive particles", in that they are particles which have mass.

[mathman]

I'm glad that's cleared up. However I have a hazy recollection that WIMPS are supposed to have a lot more mass than neutrinos. In any case neutrinos cannot account for most of non-baryonic matter, since galaxy formation couldn't take place.

[James R]

You may well be right, mathman.

[RawThinkTank]

Dark Matter is something that stops breaking of light speed barrier. When humans will solve this mystery their astronomy will become very different.

[Starthane Xyzth]

I'm glad that's cleared up. However I have a hazy recollection that WIMPS are supposed to have a lot more mass than neutrinos. In any case neutrinos cannot account for most of non-baryonic matter, since galaxy formation couldn't take place.

The main WIMPS are supposed to be heavy particles known as neutralinos and photinos, plus lighter but more abundant axions. Since none have been detected in decades of searches, however, they may not exist at all.

An alternative theory known as Modified Newtonian Dynamics (MOND) states that the gravitational constant is slightly raised in very low-density regions, such as the outer halos of galaxies, or beyond. Enough to account for discrepancies in galactic dynamics usually attributed to the presence of non-baryonic dark matter.

MACHOs certainly exist, but cannot be abundant enough to allow an absence of WIMPS without invoking MOND, or some other alternative.

[RawThinkTank]

Dark matter is actually responsible for expansion-acceleration of the universe and also for holding every thing together ie. local groups of stars, groups of groups of stars, Groups of galaxies etc, etc. Unfortunately no one can be told how, because facts are strangely simpler than fiction and todays human cosmology.

[geistkiesel]

Dark matter is actually responsible for expansion-acceleration of the universe and also for holding every thing together ie. local groups of stars, groups of groups of starts, Groups of galaxies etc, etc. Unfortunately no one can be told how, because facts are strangely simpler than fiction and todays human cosmology.


Is there anything like "scientific proof" in the existence iof this dark matter? The measuren of "excessive velociy" of orbiting stellar matter requires a plethora of agreement on many tenuos scinmtific theories, some of which are being treated as dogmantic truth, where counter claims are objects pf prevailing scorn.

Can any one tell it plain and simple why "dark Matter" is? Or must you run down the propagandists list of "compelling experimental results"? or "analysis by some of the finest minds in the scientific community"? remember the words of our greatest vice president Dan Quail, in his thoughtful ruminating when he said, "The mind is a terrible thing."

[Starthane Xyzth]

@RawThinkTank: actually, it's dark ENERGY which is believed to be causing the acceleration of cosmic expansion. Either quantum forces inherent in the vacuum, or something more exotic known as quintessence. Dark matter, whatever its nature, would still possess gravity, and hence act against the expansion.

However, it looks like the dark energy is winning out; as both dark and visible matter become ever more thinly spread, their ability to resist this force will grow ever weaker. Eventually, vacuum energy may be the only significant influence in cosmology - unless some fundamental law changes with time.

[blobrana]

Hum,
i think nasa are about to release new findings about dark Energy , from observations with the chandra space telescope...
no doubt they`ll be broadcasting at 1 pm EDT ON NASA TV....

Old news really....

[Starthane Xyzth]

Thanks, I'll keep my search-engine ears open.

[RawThinkTank]

It the Dark Matter that bends light towards black hole even though it has no weight.

So now that this thread done enough work of spreading word around of Dark Matters effects, it can be safely moved to pseudo science or to a new section called "Future Science"

[Catastrophe]

http://story.news.yahoo.com/news?tmpl=story&u=/afp/20040518/sc_afp/us_astronomy_space_040518201615&e=2

[RawThinkTank]

There is no doubt that the weight of all objects in the universe is decreasing as time is passing.
This statement is made here for the first time in human history and prediction is that it may very well come true with a spring weighing scale.

[Starthane Xyzth]

It the Dark Matter that bends light towards black hole even though it has no weight.

I think you are confusing dark matter with gravity itself. The curvature of space near a black hole is a consequence of the hole's own mass, not that of dark matter in the surrounding space. Though I suppose you could call the hole itself dark matter - a MACHO - if it is detectable only by its effect of bending light.

And non-baryonic dark matter would have weight, as long as it has mass. You just wouldn't be able to hold it and feel its wight, since it won't offer any resistance to the normal matter making up your hand.

There is no doubt that the weight of all objects in the universe is decreasing as time is passing.
This statement is made here for the first time in human history and prediction is that it may very well come true with a spring weighing scale.

If you are saying that the actual gravitational constant is decreasing as the Universe expands, this is not an entirely original idea. Paul Dirac came up with a similar suggestion.

[dragabain]

Maybe Dark Matter is like antigravity. If what RawThinkTank says is true then it would make sense that dark matter is the anti-matter (for lack of a better word) that scientists have been searching for. The laws that we currently know are for objects with positive masses. What if Dark Matter has a negative mass? Then a whole new set of rules governing the universe would be needed to accomidate this new finding. What if a negative mass area acted on light the same way that water does and bends it? What if this negative mass void was filled wouldn't this cause the universe itself to bend thus proving the theory about space bending? What if our perception of light is actually bent? Could our normal matter bend light and space one way while Dark Matter bends it in another but because of the way that our eyes work and our brains function we see the normal matter bent as normal and the Dark Matter bent as bent?

[Starthane Xyzth]

That certainly leaves one's brain feeling a little "bent", Dragabain...

If the whole Universe were filled with some sort of medium which affects the passage of light - like the old idea of a luminiferous ether - then its apparent effect would vary dependent on direction, since the Earth (and the Sun, and the whole Galaxy) have a motion of their own relative to this cosmic medium. The famous Michelson-Morely experiment disproved the existence of an ether, and its results have been duplicated many times since.

http://blueox.uoregon.edu/~karen/astro123/lectures/michelson_morley.html

The basic concept behind dark matter is that it explains the missing mass of galaxies and clusters, by adding to the gravity of observable normal matter. The anti-gravity effect driving the expansion of the Universeis normally attributed to dark ENERGY. But hey - ever since Einstein's theory, energy and matter have been regarded as interchangeable under the right conditions.

[dragabain]

I'm not familiar with that experiment was it just a light beam being bent between two mirrors and observing their path? If that is the case then you also have to look at Snells law which deals with light bending in a medium such as air and water when it enters it. If they only preformed this experiment in air and didn't have it bent through any other type of medium such as a vacuum then they really have proven that light doesn't bend when it stays in the same medium. Space is comprised of multiple mediums, I don't know what they are but my guess is mostly a vacuum. Around a blackhole the light is going to bend because it entered another medium, then another, and another, and another, untill finally it reaches the otherside and goes back to the same medium from which it left. When light does this according to snell its direction is going to be the same as which it left. I don't have a link to any of Snells stuff but if you all can find one I encourage you to look at it. I don't know if I'm spelling the guys name right because it is German after all ;)

[Starthane Xyzth]

By "multiple mediums" (media?) do you mean regions of differing spacial curvature, or different material density/composition? I suppose you could call an ionised nebula or a black dust cloud a different medium from normal interstellar space (filled with very diffuse gas known, appropriately, as the interstellar medium). Certainly, light cannot pass so easily through the first two media than the third. Light is heavily refracted and scattered by interstellar dust, but I wouldn't say that the overall direction of an incident beam is actually changed - as it is in gravitational lensing by a black hole, which you described.

[RawThinkTank]

Starthane Xyzth

There is no such thing as gravity . U humans have confused DarkMatter with gravity. Its the dark matter that is holding U down right now.

[Starthane Xyzth]

Then how come it holds things down more strongly here on Earth than it does on the Moon - and how does it explain the complex rules of celestial mechanics?

(I do know you're having a laugh).

[2inquisitive]

Perhaps we have MACHOS here on Earth and WIMPS on the moon? haha....I know, I know, but I couldn't resist!

[RawThinkTank]

This thread should have been moved to a section called FutureScience but there isnt one.

DarkMatter cropped up due to recent observations but the concept of ether is very old.

Something like ether is holding down everything on earth like things sticking to the dust bag inside a live vacuum cleaner. It seems all the matter is absorbing into it this ether, it seems to work more like air molecules. That may be the reason for not having constant acceleration.

now U can laugh.

[Starthane Xyzth]

Or maybe all matter, all external reality, is an illusion, and the Universe only exists inside your own pure think tank, RawThinkTank? I may be just another figment of your divine subconscious.

So concentrate hard and make me disappear - I welcome it!

[RawThinkTank]

The particles of DM are so small and so fast that they even keep the two particles of photon together. Naturally they are super faster than light. Hey , all the particles of atoms are also held in place by the dark matter , its fundamental. In nature there is no such thing as an attraction force because that will require some sort of chains to do that and these chains then cannot be made of smaller particles as they too will have to be held together by attraction. There cannot b anything such thing as attraction. But there can easily b finer and finer particles . ( not even waves )

[Starthane Xyzth]

You seem to be developing a fully-fledged alternative physics, Mr. Raw. Perhaps it should be collected, systemised and published? You could make some money from it, as many people enjoy reading the unorthodox.

[Zarkov]

>> In nature there is no such thing as an attraction force

You got that correct.

[Starthane Xyzth]

If fundamental forces are not attractive, what are they? Gravity can only draw objects together - there is no such thing as gravitational repulsion. Electromagnetism draws opposite charges together, and the strong forces binds nucleons together at a very short range. Aren't these effects definable as attraction?

[RawThinkTank]

What we r coming up with is undefined in science. Everybody likes to talk about forces of attraction but when asked about how they work, they turn a blind eye ( as if something is stopping them from seeing the reality ). How can something not made of particles interact with particles ? and why should we accept that without an explanation ?

But then even though it sounds boring, I am committed to this as too much is at stakes. Hell with my ego, Think how a vacuum cleaner attracts things towards it.

[Boris2]

>>>>Think how a vacuum cleaner attracts things towards it.

they don't.

[DeeCee]

Err I'm no physicist but that may possibly be an advantage here;) (It seems to work for Raw)
If I'm wrong correct me but...
The notion of dark matter/energy arises from the math because the math cannot fully explain some of the observations made by astronomers.
Kinda like Einsteins abandoned notion of a cosmological constant.
In other words..
Does dark matter/energy actually exist or is the math wrong?

I think we should at least consider the possibility.
Dee Cee

[RawThinkTank]

Boris2
Thanks U r very explanatory.

DeeCee
U got my point. The fact that many have spend good parts of their lives studying this things based on big assumptions and then using maths to prove that has made them reluctant to think beyond what they know is right. They r trapped in their own hard work.

[optic]

There is a theory in the works right that dose away with dark mater. The scientists who are working on it are rethinking constant acceleration.

[bradguth]

Try thinking "photons at rest", as in horrific collectives of such creating photonic dark matter.

? The individual resting photon mass of 6.4555e-83 gram

Photons/m3 and of photons at rest: http://guthvenus.tripod.com/gv-photons-m3.htm

QUESTIONS;
how many photons/m3 are there ?

How weak are regular photons ?

How about the mass of a resting photon ?

How many such photons (resting or otherwise) may exist or coexist/m3 ?

Could a blackhole worth of resting photons surround a seed of anti-matter ?

Are photons individual travelers, or are they being conducted along by way of FIFO nodes of atomic Oort zones ?

[bradguth]

It could be weakly-interacting massive particles (WIMPs) such as neutrinos. Or maybe it is massive, compact halo objects (MACHOs), although I think that idea may be on its last legs (not sure though).

I don't think it's a matter of comprehensibility. I think it's a matter of coming up with a good explanation.


How weak are regular photons ?

How about the mass of a resting photon ?

How many such photons (resting or otherwise) may exist or coexist/m3 ?

Could a blackhole worth of resting photons surround a seed of anti-matter ?

Are photons individual travelers, or are they being conducted along by atomic Oort zones ?

[bradguth]

How weak are regular photons ?

How about the mass of a resting photon ?

How many such photons (resting or otherwise) may exist or coexist/m3 ?

Could a blackhole worth of resting photons surround a seed of anti-matter ?

Are photons individual travelers, or are they being conducted along by way of FIFO nodes of atomic Oort zones ?