Cosmologic philosophy: dark matter is or isn't? IS? (Introduction)

by David Turell , Tuesday, April 05, 2016, 20:14 (3154 days ago) @ David Turell

One laboratory keeps seeing it. There are now four others who will try to confirm:-http://www.scientificamerican.com/article/controversial-dark-matter-claim-faces-ultimate-test/?WT.mc_id=SA_DD_20160405-"The original claim comes from the DAMA collaboration, whose detector sits in a laboratory deep under the Gran Sasso Massif, east of Rome. For more than a decade, it has reported overwhelming evidence for dark matter, an invisible substance thought to bind galaxies together through its gravitational attraction. The first of the new detectors to go online, in South Korea, is due to start taking data in a few weeks. The others will follow over the next few years in Spain, Australia and, again, Gran Sasso. All will use sodium iodide crystals to detect dark matter, which no full-scale experiment apart from DAMA's has done previously.-"Scientists have substantial evidence that dark matter exists and is at least five times as abundant as ordinary matter. But its nature remains a mystery. The leading hypothesis is that at least some of its mass is composed of weakly interacting massive particles (WIMPs), which on Earth should occasionally bump into an atomic nucleus.-***-"Could the teams prove DAMA right? “I was unwilling to believe the DAMA results or even take them seriously at first,” says Katherine Freese, a theoretical astroparticle physicist at the University of Michigan in Ann Arbor, who with her collaborators first proposed the seasonal modulation technique used by DAMA. But, in part because of a lack of any other explanation for their signal, she is now more hopeful. The fact that many have tried and failed to repeat DAMA's experiment shows that it is not easy, says Elisabetta Barberio at the University of Melbourne, who leads the Australian arm of SABRE. “The more one looks into their experiment, the more one realizes that it is very well done.'”-Comment: Like planet nine search science marches on. Fun.