Recent research suggests that the cores of galaxies, including our Milky Way, may harbor a colossal invisible star composed of enigmatic 'fuzzy' dark matter. This star could span thousands of light-years, challenging existing notions about galactic composition.
Scientists have long recognized that a significant portion of a galaxy's mass is attributed to unseen dark matter, yet its exact nature remains elusive. Traditional theories propose that dark matter consists of heavy particles that rarely, if ever, interact with light or ordinary matter. However, this explanation fails to account for the low density observed in galactic cores, where simulations indicate that dark matter should accumulate, resulting in high densities.
One proposed solution is that dark matter is made up of extremely light particles, billions of times lighter than the known particle neutrino. Researchers have termed these particles 'fuzzy' dark matter, which exhibits quantum-wave characteristics on a galactic scale. This allows them to cluster into vast aggregates, potentially forming dark stars.
These hypothetical dark stars could possess sizes reaching thousands of light-years while maintaining a relatively low mass due to the lightweight nature of their constituent particles. Consequently, they may reside in galactic cores, contributing to their overall mass without creating excessive density.
The study also emphasizes that galaxies consist of both dark and ordinary matter, such as observable gas clouds and stars. To investigate the relationship between fuzzy dark matter and ordinary matter, researchers developed a simplified model of a galaxy with a substantial amount of fuzzy dark matter and a minor quantity of ordinary gas.
The simulations revealed that fuzzy dark matter quickly consolidated into a significant clump at the galaxy's center, surrounded by dispersed clouds of dark matter. Additionally, ordinary gas mixed with fuzzy dark matter in the galactic core, resulting in the formation of a fermionic-bosonic star, which reached an astonishing size of 10,000 light-years. This star remained nearly invisible, with only the ordinary gas emitting a faint glow.
Researchers believe that these simulations lend credence to the theory of fuzzy dark matter in galactic cores. Future efforts will focus on creating more complex models to better understand the appearance of dark stars in galactic centers and to facilitate their detection.