Dark Matter May Not Be That Mysterious After All

A recent paper hypothesizes that the material that comprises most of the matter in the universe may consist of a type of theoretical particle whose signature has already been detected by scientists.

What's the Latest Development?


Vanderbilt University professor Robert Scherrer and post-doctoral fellow Chiu Man Ho have developed a hypothesis on the composition of dark matter that, unlike other attempts at explanation, can be readily tested using existing underground detectors. Their focus is on the Majorana fermion, a theoretical particle that exhibits a different kind of electromagnetism than most other particles and is undetectable unless it's moving very quickly. "If dark matter, which is thought to be moving much more slowly than it was at the dawn of the universe, is made of Majorana fermions, then that could explain why it's been so hard to spot."  

What's the Big Idea?

Scientists speculate that dark matter makes up about 85 percent of all matter in the universe. The current theory concerning its composition is that it's made of weakly interacting massive particles (WIMPs) left over after the Big Bang. However, nobody has been able to definitively detect a WIMP. Scherrer and Ho's paper, which appeared in a recent issue of Physics Letters B, predicts the rate at which Majorana fermions should appear in the underground detectors and indicates that their existence should soon be discovered or ruled out. Unlike WIMPs, Majorana fermions -- or at least their signatures -- have been detected in past research using crystalline wires.

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Read it at The Christian Science Monitor

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Scientists study tattooed corpses, find pigment in lymph nodes

It turns out, that tattoo ink can travel throughout your body and settle in lymph nodes.

17th August 1973: An American tattoo artist working on a client's shoulder. (Photo by F. Roy Kemp/BIPs/Getty Images)
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In the slightly macabre experiment to find out where tattoo ink travels to in the body, French and German researchers recently used synchrotron X-ray fluorescence in four "inked" human cadavers — as well as one without. The results of their 2017 study? Some of the tattoo ink apparently settled in lymph nodes.


Image from the study.

As the authors explain in the study — they hail from Ludwig Maximilian University of Munich, the European Synchrotron Radiation Facility, and the German Federal Institute for Risk Assessment — it would have been unethical to test this on live animals since those creatures would not be able to give permission to be tattooed.

Because of the prevalence of tattoos these days, the researchers wanted to find out if the ink could be harmful in some way.

"The increasing prevalence of tattoos provoked safety concerns with respect to particle distribution and effects inside the human body," they write.

It works like this: Since lymph nodes filter lymph, which is the fluid that carries white blood cells throughout the body in an effort to fight infections that are encountered, that is where some of the ink particles collect.

Image by authors of the study.

Titanium dioxide appears to be the thing that travels. It's a white tattoo ink pigment that's mixed with other colors all the time to control shades.

The study's authors will keep working on this in the meantime.

“In future experiments we will also look into the pigment and heavy metal burden of other, more distant internal organs and tissues in order to track any possible bio-distribution of tattoo ink ingredients throughout the body. The outcome of these investigations not only will be helpful in the assessment of the health risks associated with tattooing but also in the judgment of other exposures such as, e.g., the entrance of TiO2 nanoparticles present in cosmetics at the site of damaged skin."

Photo by Alina Grubnyak on Unsplash
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