Neutrinos Have Played a Huge Role in the Evolution of the Universe

It’s often said that we haven’t yet detected dark matter particles. That isn’t quite true. We haven’t detected the particles that comprise cold dark matter, but we have detected neutrinos. Neutrinos have mass and don’t interact strongly with light, so they are a form of dark matter. While they don’t solve the mystery of dark matter, they do play a role in the shape and evolution of our universe.

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Astronomers find a galaxy that had its dark matter siphoned away

The galaxy NGC 1052-DF4 surprised scientists by having almost no dark matter to complement its stellar population. Recently a team of astronomers has provided an explanation: a nearby galaxy has stripped NGC 1052-DF4 of its dark matter, and is currently in the process of destroying the rest of it too.

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One of These Pictures Is the Brain, the Other is the Universe. Can You Tell Which is Which?

“Science is not only compatible with spirituality; it is a profound source of spirituality. When we recognize our place in an immensity of light years and in the passage of ages, when we grasp the intricacy, beauty and subtlety of life, then that soaring feeling, that sense of elation and humility combined, is surely spiritual.” – Carl Sagan “The Demon-Haunted World.”

Learning about the Universe, I’ve felt spiritual moments, as Sagan describes them, as I better understand my connection to the wider everything. Like when I first learned that I was literally made of the ashes of the stars – the atoms in my body spread into the eternal ether by supernovae. Another spiritual moment was seeing this image for the first time:

Hippocampal mouse neuron studded with synaptic connections (yellow), courtesy Lisa Boulanger, from https://www.eurekalert.org/multimedia/pub/81261.php. The green central cell body is ? 10µm in diameter. B. Cosmic web (Springel et al., 2005). Scale bar = 31.25 Mpc/h, or 1.4 × 1024 m. Juxtaposition inspired by Lima (2009).
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The galaxy with 99.99% dark matter isn’t so mysterious any more

The dwarf galaxy known as Dragonfly 44 caused a stir recently: apparently it had way, way more dark matter than any other galaxy. Since this couldn’t be explained by our models of galaxy formation, it seemed like an oddball. But a new analysis reveals that Dragonfly 44 has much less dark matter than previously thought. In short: it’s totally normal.

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If dark matter is a particle, it should get inside red giant stars and change the way they behave

Dark matter makes up the vast majority of matter in the universe, but we can’t see it. At least, not directly. Whatever the dark matter is, it must interact with everything else in the universe through gravity, and astronomers have found that if too much dark matter collects inside of red giant stars, it can potentially cut their lifetimes in half.

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Art Installation that Demonstrates How Dark Matter Bends Light with Gravity

At the Science Gallery of Trinity College Dublin, a beautiful work of art is capturing the imagination of people all over the world. It’s called “Dark Distortions,” a work of interactive art by Dutch artist Thijs Biersteker of Woven Studio. Inspired by the ESA’s forthcoming Euclid mission, a visible to near-infrared space telescope that will launch sometime in 2022 to study the mysterious nature of Dark Matter.

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A Tabletop-sized Experiment Could Help in the Search for Dark Matter

Dark matter is one of the least understood aspects in physics.  The evidence for dark matter is from its gravitational influence on galactic scales which cannot be explained by the presence of conventional matter.  Despite its large gravitational interactions, it is notoriously difficult to learn about dark matter as it does not interact with electromagnetic fields, hence the name of “dark” matter.

But just because it is difficult to get it to interact with anything on the electromagnetic spectrum does not mean it is impossible to detect other feeble interactions it may have.  A team of theoretical physicists from Caltech have recently proposed a novel type of experiment that may just hold the key to understanding dark matter with specific types of interactions.

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There’s no evidence that dark matter interacts with any other force but gravity

HD+ molecular ions (yellow and red pairs of dots: proton and deuteron) suspended in an ultra-high vacuum between atomic ions (blue dots). Credit: HHU / Alighanbari, Hansen, Schiller

Most of the universe is made of one of two kinds of mysterious substances, called dark matter and dark energy. From all the evidence, these two cosmic components only interact with “normal” matter through the gravitational force. And a recent nuclear experiment reveals no presence of any dark contamination in the bonds between atomic nuclei to a level twenty times better than previously recorded.

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