Bizarre, star-like objects that act like single, giant atoms may be hidden throughout the universe, and for the first time, researchers have shown how these strange quantum stars could form.
By Marcus Woo | Space.com
If these objects do exist, they could help explain dark matter, the unknown stuff that emits no light and yet makes up 27 percent of the universe. They could also be behind bright, fast bursts of cosmic radio waves that have confounded astronomers and even stoked thoughts of alien civilizations.
Unlike regular stars, these so-called axion stars (if they exist) do not shine. They’re dark because they’re made of hypothetical particles called axions, a primary candidate for dark matter. Different theories predict axions to have a wide range of masses, but overall, they’re expected to be extremely light — perhaps as tiny as 10 raised to the 31st power times lighter than a proton. [Strange Quarks and Muons, Oh, My! Nature’s Tiniest Particles Dissected]
Cold, dark stars
Axions, if they do exist, would hardly interact with one another, but if gravity can coax them together, they could form a dense sphere with exotic properties unlike those of any other kind of star. That’s because axions are bosons, a class of particles that includes particles of light, or photons.