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Physicists Build Donut-Shaped Magnet To Find 'Ghost-Like' Dark Matter Particle (cnet.com)
An anonymous reader quotes a report from CNET: One of the central puzzles in particle physics is discovering what particle (or particles!) makes up dark matter — the form of matter that is responsible for 85 percent of the mass in the known universe. Some physicists believe searching for a hypothetical particle known as an "axion" could lead to a better understanding of dark matter and to hunt for it, a team of U.S. physicists have recently designed and tested a basketball-sized, donut-shaped apparatus that can seek it out.
It has been believed that axions may be detectable by looking at an unusual type of neutron star known as a "magnetar". These small, erupting stars create some of the most powerful magnetic fields in the universe. Because of their giant magnetic power, axions would be converted to radio waves in the presence of the magnetar -- and thus, detectable by telescopes on Earth. That strange cosmic phenomenon inspired theoretical physicists to create the impressively-named ABRACADABRA experiment (the full name is "A Broadband/Resonant Approach to Cosmic Axion Detection with an Amplifying B-field Ring Apparatus" so the theorists deserve a round of applause for that backcronym). The experiment consists of a donut (or "toroid") shaped device, dangled in a freezer just above absolute zero and fine-tuned to create its own magnetic field. If axions exist, the magnetic field in the middle of the donut could reveal them. The study has been published in the journal Physical Review Letters.
It has been believed that axions may be detectable by looking at an unusual type of neutron star known as a "magnetar". These small, erupting stars create some of the most powerful magnetic fields in the universe. Because of their giant magnetic power, axions would be converted to radio waves in the presence of the magnetar -- and thus, detectable by telescopes on Earth. That strange cosmic phenomenon inspired theoretical physicists to create the impressively-named ABRACADABRA experiment (the full name is "A Broadband/Resonant Approach to Cosmic Axion Detection with an Amplifying B-field Ring Apparatus" so the theorists deserve a round of applause for that backcronym). The experiment consists of a donut (or "toroid") shaped device, dangled in a freezer just above absolute zero and fine-tuned to create its own magnetic field. If axions exist, the magnetic field in the middle of the donut could reveal them. The study has been published in the journal Physical Review Letters.
Then one from our study group found an American chemistry text book with pictures. It spelled doughnut as donut, but had a picture. We exclaimed, "It is a damned torus! Why wouldn't they call it a torus? Why use this weird thing donut/doughnut". In the class Prof PJ Narayanan said, "... it says doughnut in the text book. Doughnut is like a vada but it is sweet not savoury, they make in the West..."
If slashdot is going to call itself "news for the nerds" the least it can do is to call that shape by its proper name, a torus.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Don't be so quick to dismiss dark matter! We have good reasons to speculate about the existence of a particle which doesn't normally interact with electromagnetic fields. In the example above, huge clusters of galaxies collided with each other and the ordinary matter slowed down as a result of the collision, but gravitational lensing suggests that the center of mass (i.e. dark matter) got separated during the collision. It's not a slam dunk, but it's an interesting result that suggests there's more going on than just an incomplete model of gravity.