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What do you know about dark matter?
Astronomers can infer the mass of a galaxy from the rate at which it rotates. The visible, glowing matter in galaxies (i.e., the stars) do not account for the amount of matter which we know must be there, hence we conclude that there is some additional matter which we do not see because it does not glow, or in other words is dark. Beyond that, we don't know very much about dark matter.
How do you know dark matter is present?
We know "dark matter is present because it affects the world in ways I do not know of.
Why dark energy and matter does not obey standard physics and chemistry?
Standard physics and chemistry are based on the energy and matter that we know. We do not know much about dark energy or dark matter, but only that it may exist.
Is there dark matter inside a black hole?
It is currently unknown as scientists do not even know what dark matter is.
Is dark matter related to antimatter in any way?
No, dark matter is entirely different from antimatter. For one, we know a lot about antimatter and have been able to do experiments with it and actually utilize it in some nuclear reactions. Dark matter is a theory to help understand why the universe does not behaive the way we believed it should. Galaxies are showing that they do not have enough mass to have the gravitational effects that they do, so there must be matter somewhere, this is labeled as dark matter.
Did Einstein know about dark matter?
Yes
What are some possible forms the dark matter in the halo of the Milky Way might be in?
We don't yet know enough about dark matter - or even if it really exists - to be able to speculate on what "form", if any, it might take. You have to remember that "dark matter" is entirely theoretical, based on the supposed fact that the Milky Way doesn't have enough mass to keep it together, and that therefore there must be additional matter that we can't see - "dark" matter - to keep it all together. We've never detected any, nor do we know if we CAN detect any.
How are stars dust and gas similar to dark matter?
The only similarity we know of is that they all seem to interact with gravity. Aside from that, scientists do not know what dark matter is.
What is the temperature of dark matter?
At present we do not know. It might be almost motionless, it might have a high velocity, it might have a velocity near that of light. These three hypotheses of the nature of dark are called (respectively); cold dark matter, warm dark matter, and hot dark matter.
Does anyone no if you have proof dark matter exists?
The clear answer is, we don't. We cannot detect the hypothetical "dark matter", and the only reason we are talking about "dark matter" is that we cannot actually see enough mass in the Milky Way galaxy to account for the gravity that we know must be there - because the Milky Way would fly apart with only the mass that we can see. The "dark matter" may be in the form of invisibly-dim brown dwarf stars, or black holes, or "something else". Dark matter is the "something else". Everything you read about dark matter is a guess.
How do we know dark matter must exist if we can't sense it?
Actually, we CAN sense dark matter - we just can't see it, since it doesn't interact with light or other electromagnetic waves. Dark matter shows its presence through its gravitational attraction. For example: our galaxy, the Milky Way, rotates way too fast for the amount of known matter. So, to remain stable, there must be additional matter that can't be seen. Dark matter can also be detected through gravitational lensing - the amount of gravitational lensing depends on the amount of matter. Once again, the effect is greater than what can be attributed to known matter.
Were is most of the dark matter in the milky way universe?
I dont know correctly but it may be most of the galaxy I think so! In reality we don't 'know' but our best understanding is; Ordinary matter: ~4.5 %, dark matter: 23%, dark energy: 72%. Reputedly 80% of this 23% dark matter is cold dark matter and 20% is hot dark matter. It has been said that "dark matter.... makes up more than 80% of the matter of the universe." but that is a common misunderstanding; But we MAY say; up to 96% of the mass-energy in the universe is 'dark'. We don't know what dark matter is, but in fact it only means it does not have an easily detectable 'electromagnetic cross section' so it could be electrons/ions plasma, which has a refractive index of 1.
