Was ordinary matter synthesized from mirror matter? An attempt to explain whyΩB≈0.2Ωdark

Abstract

The cosmological dust has begun to settle. A likely picture is a universe comprised (predominantly) of three components: ordinary baryons $({\ensuremath{\Omega}}_{B}\ensuremath{\approx}0.05),$ nonbaryonic dark matter $({\ensuremath{\Omega}}_{\mathrm{dark}}\ensuremath{\approx}0.22)$ and dark energy $({\ensuremath{\Omega}}_{\ensuremath{\Lambda}}\ensuremath{\approx}0.7).$ We suggest that the observed similarity of the abundances of ordinary baryons and nonbaryonic dark matter $({\ensuremath{\Omega}}_{B}/{\ensuremath{\Omega}}_{\mathrm{dark}}\ensuremath{\approx}0.20)$ hints at an underlying similarity between the fundamental properties of ordinary and dark matter particles. This is necessarily the case if dark matter is identified with mirror matter. We examine a specific mirror matter scenario where ${\ensuremath{\Omega}}_{B}/{\ensuremath{\Omega}}_{\mathrm{dark}}\ensuremath{\approx}0.20$ is naturally obtained.