Physicists in a new study have proposed a hypothesis that dark matter could be made from ultralight dark photons that heated our universe. And this theory is in agreement with new data collected by the Cosmic Origin Spectrograph on board the Hubble Space Telescope.
The science and other stuff to know
Dark photons, also known as “heavy photons” or “hidden photons”, are hypothetical particles potentially supposed to be gauge bosons for dark matter.
These hypothetical particles are expected to mix with regular photons, allowing dark photons to transform into low-frequency photons, which could heat up the “cosmic web” but in a much more efficient and diffuse manner across non-dense regions of intergalactic space.
According to the new study published in the journal Physical Review Letters, this effect is exactly what physicists saw happening in recent data collected by Cosmic Origin Spectrograph (COS). The research was carried out by scientists at SISSA in Italy, in collaboration with researchers at Tel Aviv University, Nottingham University, and New York University.
“Since dark photons would be able to convert into low-frequency photons and heat up the cosmic structures, they could well explain the experimental information,” the scientists explained.
The data from the COS suggests that the cosmic web is significantly hotter than predicted by the Standard Model. This excess heat can be accounted for by dark photons, according to the new study.
“Usually, cosmic filaments have been used to probe small scale properties of dark matter, while in this case we have used for the first time the low redshift intergalactic medium data as a calorimeter, to check whether all the heating processes we are aware of are sufficient to reproduce the data. We found that this is not the case: there is something missing, that we model as a contribution produced by the dark photon,” author Matteo Viel explained.
The discovery in this new study, of course, does not prove dark photons make up dark matter or even if they exist. However, it’s an interesting hypothesis backed up by data and could drive further studies that explore the exciting possibility of dark photons in dark matter.
While dark photons’ existence is still uncertain, just like the nature of dark matter, their potential discovery could be a major breakthrough in the understanding of the universe.