El Método

A small amount of mini-charged dark matter could cool the baryons in the early Universe Julian B. Muñoz & Abraham Loeb ABSTRACT The dynamics of our Universe is strongly influenced by pervasive—albeit elusive—dark matter, with a total mass about five times the mass of all the baryons1,2. Despite this, its origin and composition remain a mystery. All evidence for dark matter relies on its gravitational pull on baryons, and thus such evidence does not require any non-gravitational coupling between baryons and dark matter. Nonetheless, some small coupling would explain the comparable cosmic abundances of dark matter and baryons3, as well as solving structure-formation puzzles in the pure cold-dark-matter models4. A vast array of observations has been unable to find conclusive evidence for any non-gravitational interactions of baryons with dark matter. Recent observations by the EDGES collaboration, however, suggest that during the cosmic dawn, roughly 200 million years after the Big Bang, the baryonic temp