Darkmatter!

Physicist

Hi ppl,
what are you thinking on Dark matter?This is a problem in cosmology.Its not solved yet.
Its really strange!Few years ago it was told that dark matter is made of a particle neutralino.But none could not identify it.
Its really strange that we can see it but observing the result of its existence.
In our galaxy scientists ovserved that all stars are moving at almost same speed at closed to center and at the edge. So something must working.Thats darkmatter.Using its gravity. I Want more information on darkmatter.
Expecting interesting discussion in this topic. So start posting.Thank you.Bye

einstein

Many aspects of dark matter remain speculative. The DAMA/NaI experiment has claimed to directly detect dark matter passing through the Earth, though most scientists remain skeptical since negative results of other experiments are (almost) incompatible with the DAMA results if dark matter consists of neutralinos.

Data from a number of lines of evidence, including galaxy rotation curves, gravitational lensing, structure formation, and the fraction of baryons in clusters and the cluster abundance combined with independent evidence for the baryon density, indicate that 85-90% of the mass in the universe does not interact with the electromagnetic force. This "dark matter" is evident through its gravitational effect. Several categories of dark matter have been postulated.

Baryonic dark matter

Non-baryonic dark matter which is divided into three different types:

Hot dark matter - nonbaryonic particles that move ultrarelativistically

Warm dark matter - nonbaryonic particles that move relativistically

Cold dark matter - nonbaryonic particles that move non-relativistically

Bikerman

einstein

well, its only a hypothesis about the 'big crunch' , but i guess it might happen. we can't say anything unless we discover more about the dark matter.........for instance, even though i read a lot about dark matter and dark energy, i don't exactly know dark matter's STATE!!! in which state of matter does it occur??? might be plasma, but well......i don't know!!!

and by the way, if you want to know more about the composition of the universe, here is the pie chart:

so, according to me, dark matter and energy combined, which makes about 95%, may be enough to cause a 'big crunch' though its more likely that the universe will keep expanding!!!

A REAL MYSTERY!!!!!!!

MeddlingMonk

How do we know dark matter even exists? What if we've got the whole idea of the universe wrong (starting with the Big Bang) and this dark matter doesn't exist? 'Cause as far as I know, we haven't found any yet, nor is there any proof of its existence.

Bikerman

MeddlingMonk

Bikerman

stone1343

I'm with you, MeddlingMonk. I know the scientists say that the best way to explain certain things is with dark matter, I just think they could be wrong. I'm not coming at this from the point of view of a religious person, either. I don't believe in God, but I also don't believe in dark energy.

(Sorry if this is a double post)