dark matter has been used to explain pheonomena we cannot explain on paper otherwise. decades ago vera rubin, a cosmologist, discovered that there is not near enough matter in a galaxy to hold it in tact -the stars in the outer rim should just drift away from the center instead of holding in an orbit. the amount of matter missing is a startling 97%. solution: propose some kind of matter that has so far eluded detection -such as an unknown weakly interacting massive parcticle (WIMP) that has enough gravity to make up for the missing part of the equation. this has been the biggest slap in the face to scientists as we still have no idea what actually makes up this difference -decades after they were first proposed. -unless our idea of how gravity interact at great distances is incorrect.

modified newtonian dynamics (MOND) proposes that gravity is much stronger over long distances than previously thought. it could also explain why the univers appears to be expanding (not spreading apart but actually expanding according to a value called hubble's constant), the light travelling over these long distances may just be affected by gravity in ways we do not understand. the theory was created in the early 80's but hasnt got much publicity uuntil recently. part of the reason it is now being taken seriously is the pioneer 10 and 11 spacecraft phenomena.

-the pioneer craft are now at the edge of our solar system and have deviated from the course they are predicted to follow. some unknown force is redirecting their trajectory -their engines have been cold for decades, they should drift on according to gravitational pull of any bodies close enough to them, but they are a little off, and rocket scientists/cosmologists do not accept even the smallest deviation from predicted orientation. this is a very small difference. over its distance travelled over a year, 219 million miles, they drift off by 18 thousand miles.

MOND could possibly explain this problem with the pioneers, it could actually explain some of the wierdest phenomena in cosmology. the scientific community is reluctant to accept this theory as it would change newton's 2nd law of gravity -science books would be forever changed (forever?)

i highly suggest reading the book "13 things that dont make sense" by michael brooks. i also used the internet, memory from radio/television programs and a march '09 issue of astronomy monthly. -i am no cosmologist i just find this stuff interesting, i dont necessarily believe this theory, but at the same time it makes more sense than the existance of dark matter and universe inflation.

damn... thats just weird.

Thanks, found this interesting, never knew about the MOND theory.

there is another version of MOND called "Tensor-vector-scalar gravity" or (TeVeS). i no nothing about it but it is often mentioned when you speak of MOND. heres the wiki link to MOND and TeVeS:

http://en.wikipedia.org/wiki/MOND

This is possible. As it is, 3 possible explanations remain:

1. There are matter (a significant amount) that have remained undetectable.
2. Gravity a force we already recognise does not funtion they way we perceived it would at great distances
3. There is some other unknown force at work, much like the strong/weak force which was discovered much later than gravity.

I'm inclined to believe the first as there are significant heavy matter out there that would have vast amount of gravity yet no perceivable way of detectability, some stars rotate rapidly giving off a certain frequency (a neutron star for example), some can be infered simply from the absence of information (imagine a black hole). This possibility limits us to believe that we are lacking tools to detect certain other matters rather than the possibility that there is another force at work, or a known force functions in a different manner.

The second possibility I find is very interesting as there have been a similar issue as this one only in the microscopic scale. It was found much later that the force keeping an electron in orbit from the proton, is in fact not gravity (as this force is too weak), but the strong force, and that the force that keeps the orbitals of all the other electrons are the weak force (my recollection may be a little faulty here as it has been a while since I studied astrophysics). And the final fundemental force is the electromagnectic force.

The 3rd option is just as plausible as the rest as we don't know in entirety if there is a 5th fundemental force in effect but only in the macroscopic scale (much like strong/weak force only reacts in the microscopic scale).

But hopefully some better method or tool is developed so that we can isolate each of these possibility and at long last we can know for sure what the hell has been keeping our universe in tact!

p.s: However neutonian second law of motion has already been disproved to a certain extent by albert einstein (the whole point of the theory of relativity). Newton proposed that the force is proportional to the product of the mass and acceleration (the best summary of the law), however einstein pointed out that this is in fact untrue when you reach the speed of light, to make an object accelerate at a constant rate you would in fact need to apply an exponentially increasing force as you reach the speed of light, which implies that the object itself is gaining mass as it reaches speed of light.

i dunno waht the hell you are talking about

Dark matter + Anti Matter are both interesting subjects of physics.

Anti Matter has been proven to exist though.

leave it up to the jsp science & tech forum to disprove scientific theories

Interesting. but not much of a debate, as you dont really argue anything, just kind of list it.

tell me then, because you sound very interested in the subject, what do you believe and why?



yes it has. The government is collecting anti-matter. pretty sure they only have like a gram of anti-matter, maybe less.

interesting discussion guys. keep it up