Dark Matter May Exist in Two States, Explaining Missing S...

What’s Happening

So basically Learn how a two-state model of dark matter could explain why gamma-ray signals appear in some galaxies but not others.

What if not finding something is actually a clue? In the search for dark matter, missing signals in some galaxies may help explain what’s being detected in others. (yes, really)

At the center of the Milky Way, telescopes have picked up an unusual glow of gamma rays, the most energetic form of light.

The Details

One possible explanation is that dark matter particles are colliding and destroying each other, releasing bursts of energy in the process. Yet the same signal hasn’t appeared in other places where it should.

That mismatch has become one of the biggest sticking points in interpreting the signal. If dark matter is responsible, why doesn’t it show up everywhere?

Why This Matters

A new model outlined in the J ournal of Cosmology and Astroparticle Physics offers a different way to think about that question. Instead of assuming dark matter behaves the same across the universe, the work suggests its signals may depend on local conditions, appearing in some galaxies while remaining undetectable in others. “What we’re trying to point out in this paper is that you could have a different kind of environmental dependence,” broke down Gordan Krnjaic in a press release .

This could have implications for future research in this area.

Key Takeaways

• “Dark matter could straightforwardly be two different particles, and the two different particles need to find each other to annihilate.
• That makes them ideal places to look for clean signals.
• If dark matter interactions are producing gamma rays in one galaxy, similar signals would be expected in these smaller systems as well.

The Bottom Line

That gap has pushed some researchers to look for alternative explanations for the Milky Way glow, such as large populations of faint pulsars clustered near the galaxy’s center. Others see it as a sign that the simplest dark matter models may be incomplete.

Thoughts? Drop them below.