If dark matter exist, but you cannot touch, see or measure it. How can possibly exist?

Question

You cannot see its effects? nor can you view it. So why are scientist adhamant that it exist?

Answer 1

While dark matter doesn't emit or interact with light (hence it is dark), it is detectable through its gravitational effects. In fact, using graviational lenses, it has been possible to map out the dark matter in many galaxy clusters. Usually, the dark matter and the ordinary matter are pretty closely associated. But there are examples where they are not, so we really do know there is something extra out there gravitating. This extra graviation also shows up when looking at how stars revolve around galaxies and how galaxies move inside clusters.

One of the big questions right now is what the dark matter is made of. From other things we know about the universe, this stuff cannot be made from the ordinary protons and neutrons that make up most of the ordinary matter around us. There are several proposed subatomic particles from supersymmetric theories, but none have been found in the lab. This is being actively investigated.

Answer 2

Not all scientists are so adamant on this topic. It is not a scientific requirement that the universe must contract. There is no principle that we must adhere to just so we can say the universe is infinite in time, or even that time is infinite or cyclical.

Theories of the mass of the universe are based on conjecture, philosophical ideologies, etc. and not on experimentation or measurement. In other words, we could be way off, not only on the mass of the universe but also on several presuppositions about how to arrive at such a number.

Dark matter will be measurable if it exists. A popular principle in physics is that things which are not measurable, do not exist. If it is only dark, then we cannot see it in space because it generates and/or reflects insufficient light. That does not necessarily mean that we could not travel to it and feel it.

Answer 3

it truly is precisely the position faith will change right into a detriment to technology, at the same time as those of religion call for that questions be responded with the help of their faith and that medical analyze could supply up. At it really is center, it really is taking income of the logical fallacy of difficult the unexplained with the unexplanable. In different words, it assumes that when you consider that 40-60% of the universe is lacking that it's not got here across. It receives taken a touch further and concludes that because the 40-60% isn't got here across, that it really is "information" that their faith (and only their faith) is a conventional reality. it really is this form of questioning that held again medical progression for thus long. imagine of the position we will be if docs nonetheless held that disease is brought about by skill of sin. the conventional lifespan would nonetheless be 30 years, baby mortality will be very extreme, we would struggle through from many better minor (and curable) ailments. Even the fundamentalists take income of medical progression on some factor.

Answer 4

The visible matter of a galaxy is insufficient to provide enough gravity to explain the orbital speeds of stars at the edges of a galaxy. The extra mass required is termed Dark Matter.
It is therefore detected by it's effect on other matter.
If you are claiming that Dark Matter does not exist you would have to come up with a better explanation for the observed orbital speeds of stars at the edges of galaxies.

Answer 5

dark matter does not have to mean exotic matter

you can't see planets (barring very favourable conditions). You can't see dead stars (even though they're still very heavy). You can only detect neutrinos with great difficulty (their mass is non-zero and they're so many of them, that they could represent a large chunk of the total mass of the universe).

why are physicists so keen on dark matter? Because, for example, the way galaxies rotate is not in line with how they should rotate, if their mass was made of only what we can see. Typically, the sides rotate much faster than they should, and if there was only the mass we can see, then the galaxies should come apart. But they don't.

so, either we're not seeing a huge chunk of the actual mass (around 80% of it!).

or, our understanding of gravity is not quite complete.


Hope this helps

Answer 6

no more than four percent of dark matter can be ordinary matter, but the rest is unknown. there is about six times as much dark matter as ordinary matter. dark matter seems to interact only thru gravitation so its effects are observable. astronomers have found the first direct evidence of the existence of dark matter in two colliding galaxy clusters called the bullet cluster. most of the masses of each cluster seems to have passed right thru the other, but the ordinary matter is observable as gas and is colliding and producing x-rays.

http://en.wikipedia.org/wiki/Dark_matter
http://en.wikipedia.org/wiki/Bullet_cluster

Answer 7

Because they can see the effects of it everywhere (in terms of gravity), and the universe could not exist without it.

Answer 8

love does exist or not exist in the same way. you cannot touch it, mostly not see it, and definitly not measure it. and nevertheless you are feeling it, and you are sure that it exists. maybe a matter of believing?

Answer 9

It has to exist to account for the theoretical mass of the universe.

Answer 10

perhaps they can see the effects of gravity that has to be cause by something they cannot see. Gravitational pulls that effect orbits and things like that.