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In the absolute strictness sense, neither I nor anyone else can know dark matter exists. But we DO know that neither the measured velocities of spinning galaxies nor the bending of light from distant galaxies can be explained (1) by the amount of matter we can see in and between those galaxies (2) with our present understanding of gravity. Either there's some mass out there that we can't see OR we don't understand gravity as well as we think we do. Conceptually, scientists prefer solving these discrepencies with (1), as it means we simply have to add some matter to our Universe. What EVER that extra matter happens to end up being, we will, until we know better, simply call it "dark" matter. Thus, ANY use of solution (1) means dark matter exists, even if we don't know its exact nature.
Interestingly, the density of dark matter that would explain the first anamoly -- the spin velocity of galaxies -- is about equal to the density that would explain the second one -- the bending of light through inter-galactic space. This strongly suggests solution (1) for both unresolved problems.
What else can I help you with?
What is dark matter and what exists for it?
We know that dark matter exists because it got gravity, though it is invisible. It hold galaxy and Universe. There is a theory there many other parallel universe outside our universe and dark matter holds those universe up and some scientists says that dark matter are just mass of the matter of the parallel universe. It sounds crazy but that is the Law of Physics. However there is not exact explanation of what dark matter really is, so there are still Noble Prices for those who can come up with a reasonable explanation
Is dark matter Solid liquid or gas?
We do not know as we have not found any dark matter to examine. The only way we detect it and know it exists is due to its gravitational attraction of the ordinary matter we can see. One speculation when neutrinos were discovered to have tiny nonzero masses was that dark matter might be neutrinos. Another speculation is that dark matter is only ordinary matter, but its in another separate universe in a shared higher dimensional spacetime. Nobody knows.
How do you know that matter exists?
If something has mass it is matter.
Is it true dark matter cannot be seen?
Yes this is true. We have recently discovered dark matter exists with the help of the Hadron particle collider, but can not see dark matter. (not yet any way)
How long is dark matter been around?
If dark matter exists (the jury's still out on that, but it's looking pretty likely), then ... actually, you know what? We still don't really know, because we don't know exactly what dark matter IS. It may have been around since the beginning of the universe, or it may have formed slightly later. Either way, "around 13 billion years" is a good estimate.
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.
What had Astronomers have been unable to prove that it exists?
'Dark matter' and 'dark energy' have not been observed or proven yet.
Can dark matter kill you?
The whole point of dark matter ... the thing that makes it "dark" ... is that it doesn't interact with normal matter except through the gravitational force (and, possibly, for some potential types of dark matter ... remember that nobody really knows what it actually is yet ... the weak force).One type of dark matter that we know about for sure is neutrinos. Around 65 billion neutrinos per second pass through every square centimeter of your body perpendicular to the direction of the Sun. They have been since you were born ... since before you were born, in fact. Even at night, because they go straight through the Earth too and come up through the ground on the side facing away from the Sun. The kajillion that have already done so haven't killed you yet, it's not all that likely that the kajillion and first is going to kill you.About the only reasonably possible way to die from dark matter would be if there were a lot of it concentrated in one smallish area, in which case you could be pulled apart by tidal forces if you were in a spaceship that went too close to it. This also isn't likely to happen.
What are some unique info?
What exists at the center of a black hole. Why is dark matter unaffected by photons. What is dark energy. Examples...
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.
Is dark matter a reality or made up becauseof the lack of matter in the univrse?
There is a lack of OBSERVED matter, but it is quite clear (due to gravitational effects), that dark matter indeed exists. There are all kinds of pieces of evidence in favor of dark matter. It isn't known yet what it is made of.
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.
