Dark matter, the mysterious substance making up about 85% of the universe, has long been a puzzle for scientists. It interacts with regular matter but not light, making it invisible to our telescopes. However, researchers propose that dark photons, which interact mainly with dark matter, could hold the key to understanding this enigmatic form of matter.
The Big Bang’s cosmic dawn, a period after the universe’s birth 500 million years ago, is believed to be the perfect time to study dark matter’s behavior. Dark matter played a crucial role in forming the first galaxies, and its interactions with dark photons could have left behind “signatures” that can be detected today.
According to Dr. Charlotte Mason, associate professor at the University of Copenhagen’s Cosmic Dawn Center, “Dark photons are theoretical particles that extend the concept of electromagnetism into the ‘dark sector.’ They are similar to regular photons but interact mainly with dark matter rather than ordinary matter.” These interactions could have produced oscillations, or sound waves, that stopped shortly after the Big Bang.
The team suggests that if these oscillations existed, they would have influenced galaxy formation by creating regions of higher and lower density. This, in turn, could hold the secret to the large-scale evolution of the cosmos under the influence of dark matter.
To detect these signatures, scientists rely on advanced technologies like the James Webb Space Telescope (JWST) and radio telescopes such as the Hydrogen Epoch of Reionization Array (HERA). The team’s research published in Physical Review D at the end of 2024 proposes that even with current data and assumptions, one operating radio telescope could be sensitive enough to detect or rule out these signals.
The findings are a significant breakthrough, offering new insights into dark matter’s nature. Dr. Mason emphasizes that “any new insights we gain into its nature would be extremely valuable.” As the team continues to explore this period of cosmic history, they hope to uncover the secrets of dark matter and shed light on one of the greatest mysteries in physics.
Source: https://www.space.com/dark-matter-photons-cosmic-dawn