Before atomic elements came together, less than a second after the Big Bang, if particles condensed into halos of matter, these halos may then have collapsed, creating the first black holes, boson stars, and so-called cannibal stars. This is the conclusion of a new study just published in Physical Review D, conducted by a team of researchers from SISSA – Scuola Internazionale Superiore di Studi Avanzati, in collaboration with INFN, IFPU, and the University of Warsaw.
Starting from the hypothesis, proposed by some cosmological models, that in the earliest phases of the Universe there was a brief Early Matter-Dominated Era (EMDE), the authors investigated how particles might have interacted with each other, discovering that such interactions could give rise to a surprising variety of cosmic objects. The study thus shows that even in the very first instants after the Big Bang, the Universe could already be a stage for a rich and complex physical phenomenology.