What is Dark Matter? - Learn Its Properties & Particles

In summary, dark matter is an invisible form of matter that scientists are still unsure about. It is said to consist of particles that have yet to be discovered, and its properties remain a mystery. It is possible that it could be responsible for the gravitational attraction between galaxies, as well as large-scale structure in the universe. Chronos is an idea of one person's that suggests the center of a question is not relevant.
  • #1
FeDeX_LaTeX
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Hello;

What is dark matter? I have been told from numerous sources that it is simply an invisible form of matter that is undetectable by its electromagnetic radiation. However, that does not explain what it is, that just tells me that I can't see it.

What particles does dark matter consist of? What properties does dark matter exhibit?

Thanks
 
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  • #2
FeDeX_LaTeX said:
Hello;

What is dark matter? I have been told from numerous sources that it is simply an invisible form of matter that is undetectable by its electromagnetic radiation. However, that does not explain what it is, that just tells me that I can't see it.

What particles does dark matter consist of? What properties does dark matter exhibit?

Thanks

No one knows exactly what dark matter is composed of yet (or more accurately if it even exists). They think it could be unaccounted for black holes, an undiscovered type of particle, neutrinos, etc. Its only even posited to exist because of an anomaly in the way galaxies revolve ( http://en.wikipedia.org/wiki/Vera_Rubin ) that does not mesh with our present scientific model of the universe .

Here's a good documentary on dark matter:


BBC also has a good documentary on the topic:
http://www.youtube.com/watch?v=LRMdLO_My9A&feature=SeriesPlayList&p=49560DAA7B8CD529
 
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  • #3
Is it possible to ask a question here?
 
  • #4
amezcua said:
Is it possible to ask a question here?

you just asked one :).
 
  • #5
All things are possible... And, in response to the question I believe you wanted to ask, yes, you are allowed to ask questions here.

They must be relevant, though, I believe...
 
  • #6
Thanks for the encouragement.I was being disconnected before I could complete my messages.Here`s a question about Dark Matter. Is it possible that atoms existed before the Big Bang which were oriented like a disc.and they were damaged in the explosion?That would make them "visible".So we live in a universe made out of "bent"atoms. Think of a spinning bicycle wheel.It takes a lot of energy to turn with that.How much energy would it take to straighten out all the bent atoms.
 
  • #7
Add to the last question the idea of digital watches.The orientation of molecules in the number display will render invisibility possible with a small charge.Some spiders render themselves invisible by rapidly shaking themselves.They had never seen a propellor when they started doing that.
 
  • #8
One simple rule of thumb relating to explosions in a market place is that for every person killed there will be roughly 6 times more injured.That roughly fits the mismatch in the Dark Matter scenario.
 
  • #9
Simply put, dark matter is the missing mass necessary to explain the observed gravitational attraction between galaxies. Zwicky first noticed this missing mass nearly a century ago. See virial theorem and the bullet cluster for more detail. Dark matter is also necessary to explain large scale structure in the universe [filaments].
 
  • #10
Chronos .This idea of mine is just something for others more expert to play with..The centre of my question is the idea of atoms (pre-Big Bang ) being similar in shape to Galaxies which have the familiar flat layout. Many planets which arrived late in some galaxies were stuck in odd angles to the rest.Most galaxies seem to be quite well aligned . Maybe gravity between flat atoms would be too strong for them to separate. If one wanted a disc shaped atom how much energy would be needed to reshape it ? Is this question just an old "chestnut"?
 
  • #11
amezcua said:
Add to the last question the idea of digital watches.The orientation of molecules in the number display will render invisibility possible with a small charge.Some spiders render themselves invisible by rapidly shaking themselves.They had never seen a propellor when they started doing that.
no that's not the same thing. those molecules would be detectable like other molecules if they were in a nebula (if there was enough of it) it wouldn't be dark matter. those are "normal molecules" in the watches and in the spiders
Maybe gravity between flat atoms would be too strong for them to separate. If one wanted a disc shaped atom how much energy would be needed to reshape it ? Is this question just an old "chestnut"?
atoms don't have shapes, they are collections of particles in a stable equilibrium (aka like "orbit") due to their interactions (aka like gravity). the "shape of the atom" is determined by how the electrons interact with themselves mostly. but the "shape of the atom" is statistical/a "probability-cloud", aka, a picture of where the different components are more likely to be at any particular time

so it doesn't make sense to think of atoms themselves as discs or balls

i can tell you're confusing atoms with particles though. you can't have atoms that go through the big bang... the big bang came through a point too small for that, the atoms would break apart even if you could "have atoms before the big bang"

so your question could be rephrased "do particles have a sort of shape, and did the big bang alter the shape of a large set of particles that came into the universe at the start of the universe?"

that question is highly speculative... it's all over the place lol
The centre of my question is the idea of atoms (pre-Big Bang ) being similar in shape to Galaxies which have the familiar flat layout
for this to be the case, the particles would have had to be interacting with each other differently before the big bang, the big bang altering their properties. there is no particular reason to believe this. yeah there are probably a myriad of weird unkown particles in unknown multidimensional universes. but for this particular idea i think it's coming from a misconception of what particles and spacetime actually are (not that anyone knows for sure)
 
  • #12
Thanks for the discussion. I guess we'll have to wait a few more years to find more evidence for this phenomenon...
 

Related to What is Dark Matter? - Learn Its Properties & Particles

1. What is dark matter?

Dark matter is a type of matter that is believed to make up about 85% of the total mass in the universe. It is different from the matter we can see, such as stars and galaxies, because it does not emit or reflect any light. This makes it invisible to telescopes, and thus difficult to study.

2. How do we know dark matter exists?

Scientists have observed the effects of dark matter on the motions of stars and galaxies. These observations have shown that there is more mass in the universe than what we can see, and that this invisible mass is necessary to explain the behavior of celestial objects. Additionally, experiments such as the Large Hadron Collider have provided evidence for the existence of dark matter particles.

3. What are the properties of dark matter?

Dark matter is believed to be non-baryonic, meaning it is not made up of the same particles as normal matter (protons, neutrons, and electrons). It is also thought to be cold, meaning its particles move at relatively slow speeds, and to be non-interacting, meaning it does not interact with normal matter through the electromagnetic force.

4. What particles make up dark matter?

The exact nature of dark matter particles is still unknown, but there are several theories. One popular theory is that dark matter particles are WIMPs (Weakly Interacting Massive Particles), which interact with normal matter only through the weak nuclear force. Another theory suggests that dark matter particles are axions, which are hypothetical particles that have very low mass and interact very weakly with normal matter.

5. Why is dark matter important to study?

Understanding dark matter is crucial to understanding the formation and evolution of the universe. It also has important implications for our understanding of gravity and the fundamental laws of physics. Additionally, studying dark matter can help us gain insight into the structure and dynamics of galaxies and clusters of galaxies.

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