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Old Mar 7th 2015, 05:21 AM   #1
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What is Dark Matter?

What is dark matter? Does the existing of dark matter change the fundamental of physics?Does it change QFT and String Theory?If we find out some new particles from dark matter then perhap SUSY can explain them. And Superstring would be unchanged because Superstring is general enough,is that correct?

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Old Mar 7th 2015, 07:57 PM   #2
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Originally Posted by ndung View Post
What is dark matter? Does the existing of dark matter change the fundamental of physics?Does it change QFT and String Theory?If we find out some new particles from dark matter then perhap SUSY can explain them. And Superstring would be unchanged because Superstring is general enough,is that correct?
You've summed up some possibilities but not all of them. First, dark matter may be nothing "exotic" at all. It may be a collective effect of many many Jupiter sized planets in interstellar space or some similar kind of mass. It may be simply that neutrinos do, in fact, have a mass. (I recall that the electron neutrino has been measured to have a mass of a few eV but I haven't heard about any follow up to that report.) Neutrinos are produced in such vast numbers that even a small mass could have a significant effect.

Other than that we have to resort to new Physics. Superstring theory does contain some possibilities for WIMPS (Weakly Interacting Massive Particles.) SUSY is cast in the form of a slightly modified QFT so that wouldn't change anything there. And String Field Theory should cover many other possibilities.

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Old Mar 9th 2015, 01:54 AM   #3
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There is evidence of dark matter every time a double slit experiment is performed; it's what waves.

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

The Milky Way's halo is not a clump of dark matter anchored to the Milky Way. The Milky Way is moving through and displacing the dark matter.

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

The Milky Way's halo is the deformation of spacetime.

What is referred to geometrically as the deformation of spacetime physically exists in nature as the state of displacement of the dark matter.

A moving particle has an associated dark matter displacement wave. In a double slit experiment the particle travels through a single slit and the associated wave in the dark matter passes through both.

Q. Why is the particle always detected traveling through a single slit in a double slit experiment?
A. The particle always travels through a single slit. It is the associated wave in the dark matter which passes through both.

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

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

Dark matter displaced by matter relates general relativity and quantum mechanics.
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Old Mar 9th 2015, 07:16 AM   #4
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responding to mpc755

Dark matter has mass, certainly.
The whole reason for postulating dark matter was to account for the (apparent) lack of mass found when trying to match observed cosmological phenomena with (current) theories of gravity.
Note: The words in brackets do not (necessarily) reflect any personal antipathy on my part to this interpretation, I just want to emphasise that these are assumptions included in the dark matter theory.

Dark matter physically occupies three dimensional space.
By this I think you mean that in the same way that two particles of "ordinary" matter cannot physically occupy the same point in spacetime similarly neither can 2 particles of dark matter or (crucially) a particle of dark matter and a particle of ordinary matter.
This seems a reasonable supposition.

Dark matter is physically displaced by the particles of matter which exist in it and move through it.
At first glance this seems to follow automatically from your argument that normal matter and dark matter cannot co-occupy the same region of spacetime.
However, this would require the density of dark matter to be very high, such that any particle of normal matter will unavoidably be interacting with a cloud of dark matter.

By the time you get to the end of your post, you seem to be suggesting indicating that the dark matter interpretation is fundamentally flawed
In particular you seem to be suggesting the inclusion of "matter" in the name is totally incorrect and misleading.

While I think many physicists would agree that the current Dark Matter idea has serious flaws and believe that studies in this area have the potential to be hugely informative with respect to many of the current conundrums in physics (not just the cosmological missing mass), I am inclined to think that you might be streaching the idea tooo far...
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Old May 25th 2016, 08:32 AM   #5
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Dark matter

Unlike normal matter, dark matter does not interact with the electromagnetic force. This means it does not absorb, reflect or emit light, making it extremely hard to spot. In fact, researchers have been able to infer the existence of dark matter only from the gravitational effect it seems to have on visible matter. Dark matter seems to outweigh visible matter roughly six to one, making up about 27% of the universe. Here's a sobering fact: The matter we know and that makes up all stars and galaxies only accounts for 5% of the content of the universe! But what is dark matter? One idea is that it could contain "supersymmetric particles" – hypothesized particles that are partners to those already known in the Standard Model. Experiments at the Large Hadron Collider (LHC) may provide more direct clues about dark matter.
Many theories say the dark matter particles would be light enough to be produced at the LHC. If they were created at the LHC, they would escape through the detectors unnoticed. However, they would carry away energy and momentum, so physicists could infer their existence from the amount of energy and momentum “missing” after a collision. Dark matter candidates arise frequently in theories that suggest physics beyond the Standard Model, such as supersymmetry and extra dimensions. One theory suggests the existence of a “Hidden Valley”, a parallel world made of dark matter having very little in common with matter we know. If one of these theories proved to be true, it could help scientists gain a better understanding of the composition of our universe and, in particular, how galaxies hold together.

http://home.cern/about/physics/dark-matter
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Old Oct 19th 2016, 10:39 PM   #6
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Dark matter

Dark matter took so long to theorize because the point at which discrepancies form using Newtonian and modern physics models were over vast distances where up until recently it could be attributable to observational error. The further we see, the more benchmarking we can do with comparing what we expect to what we see, hence the current theory of dark matter. Overall, it would affect equations, but not in a massive way, since it's more or less a modifier on the current used equations.
Notably, while dark matter is the prevailing theory, it's not the only theory. I can't recall the names, but there are other theories that attempt to mathematically adjust for the observational discrepancies but applying Occam's razor, most scientists find dark matter the most probable theory since it makes the least assumptions.
https://en.wikipedia.org/wiki/Dark_matter
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Old Oct 20th 2016, 06:42 AM   #7
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The reason mankind can explore space is that there are still theories that have yet to be proven as well as objects to examine and study. Dark matter are the mysterious 27% of the mass and energy in the observable universe that are probably the answer to the Big Bang Theory.
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