Japanese scientists from the University of Tsukuba and the University of Tokyo have developed a cosmological model that accurately reflects the role of neutrinos in the universe’s evolution.
Neutrinos are massless subatomic particles that influence the formation of galaxies. For a long time, the matter remained more of a cosmological mystery, and at the moment, its mass is unknown.
To make the origin and distribution of neutrinos clearer for the scientific community, researchers have created a cosmological model: it accurately reflects the role of neutrinos in the evolution of the Universe. To do this, the first of all solved the Vlasov-Poisson system of equations for neutrinos with different assigned masses. The Vlasov-Poisson equation is a system of equations describing the dynamics of a plasma of charged particles, taking into account long-range Coulomb forces by means of a self-consistent field.
It was necessary to solve the equation to understand how particles move in the Universe. So Japanese scientists accurately represent the neutrino velocity distribution function and track its change over time.
Earlier models used certain approximations that could be wrong. In our work, we avoided these approximations by using a technique that accurately represents the neutrino velocity distribution function and tracks its evolution over time.
Koji Yoshikawa, lead study author and fellow at the Center for Computational Science, the University of Tsukuba
As a result, it turned out that in regions where there are many neutrinos, massive clusters of galaxies are usually present. Another important conclusion is that neutrinos suppress the clustering of dark matter and galaxies and change the temperature depending on its own mass.
Scientists hope that their work will help determine the mass of neutrinos.