MILKY WAY'S ANTIMATTER

Endless tiny black holes created during the Big Bang may lurk at the center of our galaxy, creating a prodigious antimatter factory, a new study suggests. The study could explain where the Milky Way's antimatter comes from; one of the biggest mysteries in astrophysics. Astronomers know the galactic center is saturated in antimatter because it generates a vast cloud of gamma rays when it collides with normal matter. But none of the proposed explanations for the antimatter source- which include supernovae, x-ray emitting binary stars, and the decay of dark matter- seem to provide an accurate explanation. It is clear that antimatter cannot be explained using conventional astrophysics. Instead, it has been proposed that colossal numbers of ancient evaporating black holes supply the antimatter. We know there is antimatter within the Milky Way because of the gamma radiation produced when electrons collide with their antiparticles called positrons, the antimatter equivalent of electrons. Cosmologists have long suspected that the Big Bang could have created trillions upon trillions of so-called primordial black holes which then travel through space, slowly evaporating in a process termed Hawking radiation. The new study suggests that if the primordial black holes have a mass of an average sized asteroid, they will naturally produce the correct amount of antimatter to explain observations.