Do Neutrinos Have Mass?

amyjigglypuff writes "MINOS, a joint project between Fermi National Accelerator Laboratory and the University of Minnesota, is going to attempt to uncover the mysteries of the neutrino. Scientists plan to study the mass of neutrinos, whether they are stable or oscillate, and their electromagnetic structure. If they are found to have mass, it could prove that neutrinos are responsible for the cosmic "dark matter" that has baffled scientists for decades. Here is a link for scientists and a summary for the general public."

Comments

Re:WIMPs win

[bcrowell]

Just to amplify on the parent post, there are a lot of errors in the headline:

If they are found to have mass
Neutrinos have already been proved to oscillate between flavors, and that means they have mass. This is no longer an open question. (Technically all it shows is that there's a difference in mass between two flavors, so logically one flavor could still have zero mass.)

it could prove that neutrinos are responsible for the cosmic "dark matter" that has baffled scientists for decades.
The parent post points out that this is incorrect. Also, just to clarify a point in the parent post,:
There are two types of dark matter: baryonic, which is about 4% of the "stuff" in the universe and exotic, which is about 23% of the stuff.
In physics, a baryon is anything that participates in strong nuclear interactions, the most important examples being neutrons and protons. Electrons and neutrinos are not baryons. However, cosmologists generally use the term "baryonic matter" to mean any normal matter, i.e., any matter made of atoms. The exotic 23% referred to by the parent post is a big mystery. It's not atoms, and it's not neutrinos. So what the heck is it? We'd like to know, because there's more of it in the universe than there is of atoms!