sterile neutrinos Archives

November 5, 2021November 5, 2021 by Brian Koberlein

Experiment Finds no Sign of Sterile Neutrinos

Could sterile neutrinos be a fourth kind of neutrino? Credit: IceCube - University of Wisconsin

We don’t know what dark matter is. We do know the characteristics of dark matter, and much of how it behaves, so we know what physical properties dark matter must have, but no known matter has all the necessary characteristics of dark matter. So we’re stumped.

February 9, 2021February 9, 2021 by Brian Koberlein

If Dark Matter is Made of Sterile Neutrinos, a new Survey has Narrowed Down What to Look for

We don’t know what dark matter is. We do know what it isn’t, and that’s a problem. Matter is made of elementary particles, from the quarks and electrons that make up atoms and molecules, to primordial neutrinos spread throughout the cosmos. But none of the known elementary particles can comprise dark matter, so what is it?

April 7, 2020April 7, 2020 by Paul M. Sutter

Decaying Dark Matter Should be Visible Here in the Milky Way as a Halo Around the Galaxy

A simulated image of what the X-ray emission from dark matter might be. Image credit: Christopher Dessert, Nicholas L. Rodd, Benjamin R. Safdi, Zosia Rostomian (Berkeley Lab), based on data from the Fermi Large Area Telescope

Astronomers are very sure that dark matter exists, but they’re not sure at all what it’s made of.

The problem is that it isn’t just dark, it’s invisible. As far as we know, dark matter doesn’t emit light, absorb light, reflect light, refract light, scatter light, diffract light, or really have anything to do with light at all. This makes it hard to study. We know that dark matter exists, however, through its gravitational effects. Even though it’s invisible, it still has mass, and so the dark matter in our universe (which, by the way, makes up 85% of all the mass in the cosmos) can affect the motions of normal (or light-interacting) matter, like stars and galaxies.