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Offline The Scientist

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What is Dark Matter?
« on: 19/12/2010 10:52:49 »
We know that:
Dark matter = mass
Dark matter ≠ matter
Dark matter ≠ electrical magnetic

There is a 77% prove it exist (if I remebered correctly).

So SPECIFICALLY, what is DARK MATTER? I hope this puzzles you as much as I do.  ;)


 

Offline Chemistry4me

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What is Dark Matter?
« Reply #1 on: 19/12/2010 11:15:19 »
I hope this puzzles you as much as I do.  ;)
Well if you type 'dark matter' into the search bar you get 16 pages of results!
 

Offline The Scientist

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What is Dark Matter?
« Reply #2 on: 19/12/2010 11:17:00 »
I hope this puzzles you as much as I do.  ;)
Well if you type 'dark matter' into the search bar you get 16 pages of results!

I infer that it is something hard to explain?
 

Offline graham.d

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What is Dark Matter?
« Reply #3 on: 19/12/2010 12:09:30 »
Nobody knows what dark matter is. Its presence may be deduced from the gravitational effects it has, specifically on the rotation of galaxies and clusters of galaxies. The velocities of stars in the galaxies (or of galaxies in clusters), in relation to the distance from the centre of rotation seems only to be explicable if there is a sphere (not a disc) of gravitationally attractive matter around the galaxy (or cluster). This matter is not visible (does not interact electromagnetically) hence the name "dark matter". I think it also possible to conclude it doesn't interact with itself very much either or it would have probably formed into a disc also.
 

Offline Bill S

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What is Dark Matter?
« Reply #4 on: 19/12/2010 18:56:01 »
Could it be a re-incarnation of the aether, or even the crystal spheres?
 

Offline imatfaal

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What is Dark Matter?
« Reply #5 on: 20/12/2010 11:45:50 »
Could it be a re-incarnation of the aether, or even the crystal spheres?

No it's less unknown than that - whilst we do not know what it actually comprises, we are pretty damn certain that it exists.  Google 'bullet cluster' which provided the first evidence for physical dark matter; before that dark matter had arisen as an inference from anomalous rotational calculations of galaxies and extreme gravitic lensing results.

IIRC correctly; the bullet cluster is in the midst of a galactic collision, (we can ignore the stars which even in a cluster are too far apart too acutally collide with any regularity and make up only a small part of the mass) the interacting and luminous baryonic matter (dust/gas etc) of each cluster has collided,is clumped, very hot, and giving off x-rays, whereas the weakly interacting ie dark matter has passed through.  The baryonic matter makes up a significant proportion of the ordinary matter of a galaxy or cluster - and yet when using gravitational lensing to determine where the mass of the cluster is situated, it is not where the dust is all colliding, it is way out with the non-interacting stars.  The hypothesis is that the stars and the dark matter of the galaxies passed straight through each other and the dust crashed into each other; the fact that the dominant part of the mass of the galaxies has followed the non-interacting part lends great credence to the idea that much of each galaxy is composed of weakly interacting darkmatter.
 

Offline lennonmichael

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What is Dark Matter?
« Reply #6 on: 23/12/2010 13:15:39 »
Galaxies in our universe is not composed exclusively of things we can see, but it is held together by the gravity of dark matter itself. We should not assume that everything is visible and should not be surprised by this discovery.
 

Offline graham.d

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What is Dark Matter?
« Reply #7 on: 23/12/2010 14:09:54 »
I'm not wholly sure I agree that we should be "not surprised". I think it depends on how much you know. People with a good and reasonably up-to-date knowledge of particle physics and quantum mechanics may not be surprised as they know that there are particles that exist that do not interact with ordinary matter very much and are charge neutral (like a neutrino for example). And people with very little knowledge of any physics may not be surprised, as they would not know what to expect or have much knowledge of preceding ideas of how the universe might work. However most of those people, with a little knowledge of such things, did find it surprising. It was not surprising that there was matter we could not see but that there was a huge amount of it and that it was clearly not like the ordinary matter we are used to (but merely cold) but actually non-interacting.
 

Offline The Scientist

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What is Dark Matter?
« Reply #8 on: 23/12/2010 14:52:16 »
It all seems interesting. Do you think we're able to find dark matter on Earth? Welcome lennonmichael btw.  ;)
 

Offline graham.d

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What is Dark Matter?
« Reply #9 on: 23/12/2010 23:27:13 »
It all seems interesting. Do you think we're able to find dark matter on Earth? Welcome lennonmichael btw.  ;)
I think there is a good chance. It seems well distributed. The problem will be more in detecting it rather than there actually none being here.
 

Offline rwjefferson

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What is Dark Matter?
« Reply #10 on: 06/02/2011 00:39:48 »
dark matter.101

1. What else did einstein not imagine?
2. What property do firmament and sphere and epicycle upon epicycle and warp and string of spacetime fabric hold in common?
3. Is geometry the same as force?

...So SPECIFICALLY, what is DARK MATTER? ...

Dark Matter is a Name ...for the quantum particles that constitute spacetime aether.
Atomic Matter is a State ...of the electromagnetic particles that constitute earth's molecular atomsphere.

Could it be a re-incarnation of the aether, or even the crystal spheres? 

4. Aether is not disproved.
Don't get me started on propagation of dogma by holy science authority. -Doh. Too Late. Again.

It all seems interesting. Do you think we're able to find dark matter on Earth?

Interesting does not come close to render the justice of seeing something once again for the very first time.

5. Stand on a scale; look up.
Measure the relative aether wind. Or not. As you wish.
Imagine the eye of a cyclone reduced to a singular point. Better still, look up through the eye of hubble; try to find the only one. Or not. As you wish.

6. The force of all and everything is inertial differential.
7. Space is all so fluent.
8. Bernoulli predicts topspin lift. Really.

Kind and well reasoned questions and comments are all ways greatly appreciated.

Quote from: a.einstein
We don't need to think more, we need to think differently.

peace
rwj~

Consider the tail of dark spacetime monkeys. Called by sum as gravitons, they fly and gravitate toward massive spacetime bananas even as they are repulsed by energetic spacetime bananas.
 

Online yor_on

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What is Dark Matter?
« Reply #11 on: 06/02/2011 05:05:15 »
Take a look here.

"Dark matter: this generally refers to "exotic" non-baryonic matter that interacts only weakly with ordinary matter. While no such matter has ever been directly observed in the laboratory, its existence has long been suspected for reasons discussed in a subsequent page. This form of matter also has no cosmologically significant pressure.. Dark energy: this is a truly bizarre form of matter, or perhaps a property of the vacuum itself, that is characterized by a large, negative pressure. This is the only form of matter that can cause the expansion of the universe to accelerate, or speed up.
 

Offline graham.d

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What is Dark Matter?
« Reply #12 on: 06/02/2011 18:22:13 »
"Dark Matter is a Name ...for the quantum particles that constitute spacetime aether." - rwjefferson.

rwj, you are confusing dark matter with dark energy, I think.
 

Offline rwjefferson

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What is Dark Matter?
« Reply #13 on: 15/02/2011 03:15:01 »
Energy and matter tend to be dark and confusing for those that believe geometry is the same as force. The energy that spins and condenses galaxies into vortices is carried by the aether wind.
 
Energy is equal in verse opposite mass by spacetime constant. Mass is gravity; energy is anti gravity in verse right angle. What happens as countless suns convert immeasurable mass in verse eons of time?
think in verse as in crossing over
by right angle

Please focus just one singular bit closer to the images graven [nofollow] by the foundation of science authority.
.02. What properties do flat and hyperbolic and spherical and epicycle upon epicycle and dark matter upon dark energy hold in common? What is the difference between exotic non-atomic matter and fluxions in verse fluent gravitons?
Is geometry the same as force? Really?

ItS
truth
r~

sum questions answer them selves
even as you are unwilling

 

Offline bardman

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What is Dark Matter?
« Reply #14 on: 15/02/2011 18:37:03 »
Dark matter = mass
Dark matter ≠ matter
Dark matter ≠ electrical magnetic

Dark matter is matter which creates observable gravitational fields. Dark matter is called dark for the reason that it does not "shine," which means that it does not emit or reflect light. Thus, it must act via the weak interactions, I cannot recall the reason it is not baryonic in nature (ergo no strong interactions either). However, the known leptons associated with the weak interaction have been ruled out, much to their minuscule mass. One suggested theory, I first came across in Robert Kirshner's "The Extravagant Universe," is that there are undiscovered particles sitting out there waiting to be discovered. This is a largely improbable theory, due to last century's advancement in particle physics. It is unlikely that we have not found all the stable, relatively massive particles.
 

Offline imatfaal

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What is Dark Matter?
« Reply #15 on: 15/02/2011 19:20:58 »

Dark matter is matter which creates observable gravitational fields. Dark matter is called dark for the reason that it does not "shine," which means that it does not emit or reflect light. Thus, it must act via the weak interactions, I cannot recall the reason it is not baryonic in nature (ergo no strong interactions either). However, the known leptons associated with the weak interaction have been ruled out, much to their minuscule mass. One suggested theory, I first came across in Robert Kirshner's "The Extravagant Universe," is that there are undiscovered particles sitting out there waiting to be discovered. This is a largely improbable theory, due to last century's advancement in particle physics. It is unlikely that we have not found all the stable, relatively massive particles.

Why must it interact through the weak force? - why not just gravitationally? There are thoughts that it could be made up of the super-symmetric partners of our known particles (which must be much more massive).
 

Offline bardman

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What is Dark Matter?
« Reply #16 on: 17/02/2011 18:30:08 »
I had not considered it only interacting via gravitation, although, I cannot think of one particle that does not interact via one of the other three forces. Since the other two were ruled out, I assumed the weak was all that is left. But, you may be right in saying that there are theories along those lines.

I thought that sparticles still interacted through the same forces as their partners. However, I am not very familiar with superpartners and what you're saying may be the case. What are the expected lifetimes on these though? Are there stable configurations?
 

Offline imatfaal

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What is Dark Matter?
« Reply #17 on: 18/02/2011 10:59:00 »
Bardman - the point is, how would we know of the existence of a particle that did not interact via EM/Strong/Weak? . We could only know of if via its gravitational effect- ie we can only detect via interaction.  At present we only have gravitational evidence for dark matter (galactic rotation and light lensing); so without a free-standing theory that requires weakly-interacting massive particles that makes further testable predictions I don't see the reason to postulate anything more.  I think the weak interaction is postulated as it enables the particles to form halos - if no mechanism to remove energy/angular mom then gravity isnt enough to allow formation of clouds/haloes

On the super-symmetric side - I think the postulate mass is so high that they are likely to decay and there is no way we are even close to being able to produce them in the lab to check this out.  But as super-symmetry (acc some theories) must be conserved ie sparticles can only decay to energy and other sparticles - then there is the possibility that there are clouds of these forming at least part of the dark matter halo.  Its all up in tha air and guesswork at present though.

 

Offline bardman

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What is Dark Matter?
« Reply #18 on: 18/02/2011 14:56:55 »
I see what you mean. I think scientists are hoping these particles of dark matter do interact via the weak because we are trying to detect neutrino emissions from the dark matter. I do believe that is one branch of the Antarctica Ice Lab's research, along with cosmic rays.
 

Offline kornbredrsqar

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What is Dark Matter?
« Reply #19 on: 18/02/2011 20:39:27 »
Here's something to ponder, what if we think of dark matter as an ocean of photons and all larger forms of matter are made up of molecules that are soluble and or saturated in them. now let's think about light in the same way we understand sound, it moves through a medium in waves of a presice range of frequencies caused by vibrating molecules ,but as the sound travels the molecules do not , at least not very far and only in a back and forth motion as they are compressed and then expand back to ambient pressures. my theory is this, light waves travel through this vast ocean of photons ,"dark matter" in the same way and the individual particles are compressed and relaxed in these waves of vibration and  these movements are what we perceive as light.
« Last Edit: 18/02/2011 20:47:24 by kornbredrsqar »
 

Offline bardman

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What is Dark Matter?
« Reply #20 on: 19/02/2011 16:09:33 »
Right away I see a problem right away in trying to make a single photon (not in terms of your theory) travel through space. It should theoretically disturb the rest of the sea of photons noticeably. Meaning that we would register other photons on a screen if we were to "shoot" a "single" photon at a screen.
 

Offline kornbredrsqar

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What is Dark Matter?
« Reply #21 on: 19/02/2011 17:53:19 »
maybe you have a valid point but this brings to mind something , and the name escapes me now , its the device with multiple pendulums and as you let one collide with the others the energy is transferred to the other end causing the last one to swing and then the energy is reversed. this principle is similar to what we base our understanding of electricity on as well as other laws of physics is it not.
« Last Edit: 19/02/2011 18:05:31 by kornbredrsqar »
 

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Offline SOEDan137

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What is Dark Matter?
« Reply #22 on: 19/02/2011 20:11:07 »
Shrunk
BLACK HOLES, EXPANSION, AND DARK ENERGY

In the continuum of space and time, exists the dichotomy of matter and energy. All things exist as both matter and energy, but are experienced as one or the other.
As energy, all things exist as wave patterns. Most wave patterns are interferences of simpler wave patterns. The simplest wave forms are those that do not interfere with other waves. These simplest wave forms hold their shape as they propagate. There are three such wave forms.
The first such wave form is seen in three dimensions as the spherical expansion wave of a bomb blast, and in two dimensions as the circular wave of expansion on the water where a rock was tossed in. The second wave form is seen in three dimensions as the cone of sonic boom following an aircraft traveling faster than sound, and in two dimensions as the V-wake on the water where the boat is traveling faster than the water wave. The third wave form is seen in three dimensions as the propagation torus of a smoke ring and is seen in two dimensions as the double vortexes of an oar stroke on the water.
The Torus is a particle of discrete exchange, from one point to another. The object exchanges position and momentum. While the spherical wave shows position, and the conic wave shows momentum, the torus shows both at the same time, and has a dynamic finite unbounded reality. The volumes of the cone, sphere, and torus are mathematically related as static objects.
The Universe is a local density fluctuation. (a wave pulse) On this local density fluctuation wave, lesser wave forms may exist. All simple wave forms are also local density fluctuations, and as such are indeed universes in their own right, where other waves may exist.
Consider the torus as a universe. Einstein said that gravity is indistinguishable from acceleration. There is both linear acceleration and angular acceleration. Although the torus as a whole travels in a straight line, every local point on the torus travels in a circle and experiences angular acceleration.
The rubber sheet model of gravity and curved space translates directly to the propagating torus with angular acceleration. Acceleration is downward on the rubber sheet and outward on the torus. The tension field that separates the inside of the torus from the outside holds its shape as a simple two dimensional field of space and time just as the rubber sheet does.
Experimentally verifiable is that a big fat slow smoke ring generated in a room with very still air will eventually possess a bulge that travels in a circle on the surface of the smoke ring. This bulge, being a gravitational depression, gathers more of the energy of the field toward itself. Finally the bulge gathers enough material to collapse the field and eject a new, smaller smoke ring out in the same direction as the first torus. This collapse is a black hole to the first torus, and a white hole to the second torus, where the axes of space and time in that second torus have reversed.
While gravity tends to draw depressions together locally on a dynamic torus, even to the point of field collapse, other areas on a torus expand and contract globally as the torus propagates along without regard to local phenomenon on the surface. This is quintessence. The inertia of the torus to propagate is its dark energy. This is a two-dimensional example of the process that we  experience in three dimensions.



--
Dan Echegoyen
Please don't use this forum to plug your own new-theory website, especially on your first post! - Mod
« Last Edit: 21/02/2011 04:40:47 by JP »
 

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Offline rwjefferson

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What is Dark Matter?
« Reply #23 on: 21/02/2011 01:56:37 »
Shrunk
...So SPECIFICALLY, what is DARK MATTER? ...

..........The Torus is a particle of discrete exchange, from one point to another....................

If you meant to imply Dark Matter might be MADE UP of Torus Particles; you might just as well be right.

What do a flat rubber circle and a cone and a sphere and a torus and an epicycle upon epicycles hold in common?
Can you warp electromagnetic fabric by the three basic states of force?
Can you prove the geometry of a torus is the same as the force of gravity?

ItS
truth
r~

author of
« Last Edit: 21/02/2011 04:42:30 by JP »
 

Offline bardman

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What is Dark Matter?
« Reply #24 on: 23/02/2011 15:12:53 »
If you are talking about electroweak theory, I think you are right. As I remember it, the photon (carrier for electric force) is transferred along a line of "virtual" electron-positron pairs much in the same way as the pendulum device. Although, it does not turn around like the device.
 

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