Yeah, the weak force is actually really hard to understand intuitively, we don't see it on macroscopic levels the same way we see gravity and E&M, and it's not as obvious as the strong force which can hold together the positively charged quarks in a proton. Mostly, it is seen in forms of radioactive decay when a proton turns into a neutron, or when a neutron turns into a proton. These are beta decays, which are different from alpha decay where a helium nuclei is emitted. It is fairly weak, which is why some unstable elements can take a very long time to decay, (the half life of tritium is pretty damn long).

The experiments to detect dark matter aren't actually trying to stage beta decay, they're looking for a weak interaction more similar to the E&M we are more familiar with. Here, a cosmic dark matter particle comes flying through the detector, and puts a small force on a nucleus in the Germanium crystal. The nucleus moves, and causes a wave throughout the entire lattice which can be measured directly. It's like hitting the lattice with a hammer. Of course, a lot of things can hit the lattice like a hammer, which is why the experiments are in the deepest mines to provide some shielding from all the stuff that's flying around the atmosphere.

http://en.wikipedia.org/wiki/Supernova_1987a

Right now, the direct searches for dark matter are more similar to experiments that look for neutrinos from astrophysical sources. The evidence strongly suggests that there is a population of dark matter particles in the galaxy, and all dark matter experiments are looking for these particles.

In the very near future, the particle accelerator at CERN hopes to achieve energies high enough to create dark matter particles in the laboratory environment. If it does, we won't actually detect the dark matter particles directly, but rather by the same methods which the neutrino was originally discovered, by finding massive amounts of energy unaccounted for after particle collisions. There will not be enough particles created to detect them directly, the interaction is just way too weak, and gravity of individual particles is practically non-existent.

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

"In this experiment, now known as the neutrino experiment, neutrinos created in a nuclear reactor by beta decay were shot into protons producing neutrons and positrons both of which could be detected."

Are the experiments to detect dark matter similar? What i mean is this: For neutrinos it was theorized that they were present in radioactive decay and nuclear reactions. those are both events that we can stage on earth in a laboratory. So scientists were able to run an experiment that would in theory create neutrinos, and so they just had to figure out how to detect them once they were created. that was done by smashing them into protons.

so for dark matter do we have an idea as to how to create it in a laboratory environment? and if created could we detect it by smashing it into something else or maybe by watching how it affects a gravitational field (or how it affects the weak force like you mention above)? or does the experiment instead rely on the constant stream of dark matter rushing around everywhere all the time?

A neutrino does have a lot in common with the proposed dark matter particle. It does not interact with the electromagnetic force, they're all around us, they rarely interact with other particles, etc. There is one distinct difference, there are a LOT of neutrinos. Neutrinos are actually a bi-product of quite a few quantum mechanical processes. A lot of radioactive decay produces neutrinos, and the sun produces neutrinos as it burns hydrogen into helium.

It was through observations of these processes that people first realized the neutrino must exist. They found that they could not account for all of the energy during radioactive decay, some energy seemed to just disappear. This violates the law that energy must be conserved, so it quickly became obvious that the original theory needed to be updated to include a new particle. Fortunately, the sun creates a lot of these unseen particles, so we can now almost routinely detect them, now that we know what we're looking for.

We're not so lucky with dark matter. We don't believe dark matter particles are routinely created or destroyed, and we don't believe there are as many dark matter particles as there are other more familiar particles. This may be counter-intuitive, since I described before that dark matter makes up a larger fraction of the universe than does normal matter. The difference is the mass, one dark matter particle is suspected to be 100s of times more massive than a single proton. The relatively small number of particles makes dark matter much harder to detect than the extremely common neutrino.

We actually have a pretty good understanding of neutrinos, but a lot of work needs to be done. We have estimates of the number of neutrinos in the universe, and we know they have a mass, but we don't know what that mass is. It is extremely small, too small to be a major component of unseen mass haloes around clusters or galaxies.

Let me say that, yes, all of your points at the beginning are right on. Now, for your questions: if I'm standing in the cloud of dark matter, I still would not see anything or feel anything, because both our sense of vision and our sense of touch are driven by the electromagnetic force.

How is this??? We see by capturing photons from an object. We use our sense of touch by feeling the pressure of particles against our skin. That pressure is caused by the electromagnetic force. Dark matter does not interact with this force, making it impossible to see or touch, even when it's right in front of our faces (which it probably is).

So what is dark matter? We don't think it is antimatter. Antimatter actually falls into the "normal" category, a weird concept and yet another topic worthy of a future post. We do, however, believe that dark matter is made up of particles, and as I hinted in the last paragraph, we think these particles are passing through me as I write this.

There are a lot of very complicated reasons we believe that dark matter particles exist. I cannot possible explain these in everyday terms in a 300 word article, much less a 30000 word article.

Given this impossibility, I will be daring and summarize the reasons in one sentence: we believe another type of particle must be out there to balance the abundance of matter compared to antimatter, and to balance the difference between the way an electric force behaves compared to the magnetic force.

We have experiments underway to directly detect dark matter particles. They are actually looking for an interaction through a force I have not talked about, the weak force. These particles would then be known as WIMPS, or weakly interacting massive particles. No one has seen anything yet, but I am optimistic that they will in the next 5-10 years.

I've just breezed through a ton of material in this response, if you want to do some further reading, see the following web pages:

weak force:
http://hyperphysics.phy-astr.gsu.edu/hbase/forces/funfor.html
dark matter:
http://en.wikipedia.org/wiki/Dark_matter
WIMPS:
http://en.wikipedia.org/wiki/WIMP
antimatter:
http://livefromcern.web.cern.ch/livefromcern/antimatter/

And keep the questions coming…