(CNN)Nearly a mile under the Black Hills of South Dakota sits a canister of the atomic element xenon, chilled cold enough to turn it to liquid. The canister is the Large Underground Xenon, or LUX, detector -- the most sensitive dark matter detector in the world. But the results of a new analysis by the LUX Collaboration has left scientists perplexed about a substance that has guided the formation of the stars and galaxies since the cosmos began: dark matter.
The second reason for the popularity of the WIMP idea is that it explained a mystery in particle physics. The recently discovered Higgs boson has a mass of about 130 times that of the proton. Theoretical considerations predicted a much larger mass, but if a WIMP exists, it is easy to reconcile the prediction and measurement. These two reasons account for the popularity of the WIMP idea and are called "the WIMP miracle."
The LUX measurement is simply the most recent and most powerful of a long line of searches for dark matter. They found no evidence for the existence of dark matter and were able to rule out a significant range of possible WIMP properties and masses.
Now this doesn"t mean the WIMP idea is dead or that dark matter has been disproven. There remain WIMP masses that haven"t been ruled out, and there exist other possible dark matter candidates, including objects called sterile neutrinos, which are possible cousins of the well-known neutrinos generated in nuclear reactors and in the sun. Another recurring proposed dark matter particle is the axion, suggested in the 1970s to explain mysteries in the asymmetry of subatomic processes. (Although neither sterile neutrinos, nor axions, have been observed).
Nobody knows what the final answer will be. That"s why we do research. But there is no question that there is a mystery in the cosmos. Galaxies don"t act as we expect. The LUX measurement is a powerful new bit of information for astronomers to consider and has added to the general confusion, forcing scientists to take another look at ideas other than WIMPs.
All this reminds me of the old Buffalo Springfield song: "There"s something happening here. What it is ain"t exactly clear ..."
Read more: <a href="http://www.cnn.com/2016/09/07/opinions/dark-matter-analysis-lincoln/index.html">http://edition.cnn.com/</a>
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