Researchers propose that ancient gravitational waves in the early universe produced particles that became dark matter. The study by scientists from Johannes Gutenberg University Mainz and Swansea University suggests a new mechanism involving stochastic gravitational waves converting into fermions. Published in Physical Review Letters, the work addresses a key mystery in cosmology.
Professor Joachim Kopp from Johannes Gutenberg University Mainz and the PRISMA++ Cluster of Excellence, along with Dr. Azadeh Maleknejad from Swansea University, have introduced calculations showing stochastic gravitational waves could generate dark matter particles shortly after the Big Bang. These waves, remnants from the universe's chaotic infancy, differ from those produced by black hole mergers and instead form a faint background from early cosmic processes like phase transitions or primordial magnetic fields. Kopp stated, 'In this article, we investigate the possibility of gravitational waves -- which are believed to have been ubiquitous in the early universe -- being partially converted into dark matter particles. This leads to a new mechanism of dark matter production that has not been researched before.'