A recent study by a team of astrophysicists suggests that an exotic form of dark matter known as “dark photons” could be the reason for the observed higher temperatures in the intergalactic gas in our universe. The study, which was published in the journal Physical Review Letters, proposes that these strange particles are the carriers of a new, fifth force of nature that normal matter does not experience.
The team used sophisticated computer simulations to come to this conclusion, after observing that the clouds of gas that scatter between galaxies are a little too hot. The simulations predict that these gas clouds should be just a little bit colder than what is currently observed, suggesting that something is heating up these clouds that isn’t currently accounted for in our astrophysical simulations.
One possible explanation for this discrepancy is the presence of “dark photons” in our universe, the study authors claim. This is a very hypothetical form of dark matter, the mysterious, invisible substance that accounts for roughly 80% of all the mass in the universe, yet doesn’t seem to interact with light. Dark matter has been a topic of intense study for decades, with scientists still trying to understand its identity and behavior.
The team suggests that instead of dark matter being made of invisible particles, it would instead be made of a new kind of force carrier – a type of particle that mediates interactions between other particles.
The study suggests that we could find such dark photons by observing the intergalactic gas using what’s known as the Lyman-alpha forest. When we observe light from a distant, bright object, like a quasar, there is a series of gaps in an otherwise smooth spectrum of light from that faraway object. These gaps, known as the Lyman-alpha line, are caused by the light filtering through billions of light-years of gas, and can also be used to measure the temperature of each gas cloud.
The field of dark matter research is wide open with possibilities as to what it could be, and this study provides a new avenue for scientists to explore in their quest to understand the universe.