Astronomers have long suspected the existence of dark matter, a mysterious substance that is thought to make up about 85% of the universe’s mass. However, dark matter has proven difficult to detect, as it interacts very weakly with normal matter and light. A new theoretical study suggests that dark matter may generate detectable radio waves as it interacts with plasma waves in Earth’s ionosphere. If confirmed, this discovery would provide a new way to study dark matter and could help us to better understand its properties.
The study, which was published in the preprint server arXiv, explores models of ultralight dark matter that interacts extremely rarely with normal matter. This type of dark matter is thought to be millions of times lighter than the lightest known particles, and it could act in very strange ways. In particular, instead of appearing as individual point-like bullets, this dark matter would slosh around the cosmos in a wave-like manner.
The researchers discovered that as these dark matter waves pass through Earth’s ionosphere, they could interact with plasma waves in the ionosphere. This interaction could produce a resonance that amplifies the interaction and produces radiation in the form of radio waves. The radio waves produced by this interaction would be barely detectable, but the researchers found that by using a carefully tuned radio antenna to search for a specific frequency of radio waves over the course of a year, they might be able to detect these waves.
This idea is especially promising because Earth’s ionosphere offers several advantages over other sources of dark-matter-produced radio waves. For one, the ionosphere naturally reflects many radio waves from deeper space, making it relatively devoid of contaminating signals. Second, the ionosphere is right above us, easy to access, and already the subject of constant monitoring and study.
It’s important to note that this is a highly theoretical study, and it would take years, if not decades, to perfect the observation technique to search for these radio waves. However, if successful, this technique could provide a new way to study dark matter and could help us to better understand its properties.
