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Dark Matter Discovered Near Solar System?
gpronger writes "The ATIC (Advanced Thin Ionization Calorimeter) has potentially discovered the presence of dark matter close (only 3000 light-years) to our solar system. The system detected a large-amount of high energy cosmic rays which match the theoretical signature of dark matter annihilating itself. The universe is believed to be composed of about 25% dark matter, but there has been little evidence of it. This discovery, if correct, would be the first."
The paper was published in Nature , but it requires a subscription to see beyond the abstract.
...They have an energy dependent signal....
So there is a signal, but what produces it is still only a conjectural speculative interpretation of an observation. From experiments here at home, such radiation is ONLY and ALWAYS produced by charged particles. Instead of dark matter, the radiation could be produced by naturally occurring interstellar or intergalactic particle acceleration. It could even be some space alien's giant version of the LHC. All we observe is lots of radiation, but then they are guessing what produces it. If it is dark matter, then there should also be dark antimatter.
We know from measurements that the sun produces or is involved with an enormous amount of electrical current we call the solar wind. Even though the earth intercepts only a minute fraction of this, some strong outburst of solar electricity has shut down power grids and communication systems.
Even if there is an interstellar electric field of only millvolts per kilometer, the vast distances of space can still accelerate charged particles, mostly electrons, to immense energies. These could produce much radiation when they encounter intense magnetic fields we have observed. Annihilation of any sort is only one other, far less likely possibility.
All theory is gray
http://en.wikipedia.org/wiki/Technetium-99m
There are lots of reactions that produce EM radiation. This one is used in medical imaging. Positron-electron annihilation also creates gamma rays. Yes, those are charged particles, but the gammas are not produced by the charges moving. That reaction is also used every day in medical imaging.
All these resources available on the Internet and you can't even educate yourself. Such a waste.
OK, so scientists look at how galaxies behave and notice that they are behaving as if they had more mass than we can observe them having. Now there are two options: either 1. galaxies contain mass that hasn't been observed or 2. the theories of how the gravity works need to be revised. Both of these options are being studied, and so far the 'unobserved mass' hypothesis seems to explain obsrvations pretty well.
According to you, however, option 1 should have been discarded in the first place, for some ideological reason.