Dark matter as a manifestation of gravity

The scalaron in metric f(R) gravity can be a dark-matter candidate if its mass lies in the range between around 4.4 meV and 1.2 MeV. The scalaron manifests itself as an almost sterile cold dark matter, and its possible observational verifications would consist in measuring specific Yukawa gravitational forces on submillimeter spatial scales or detecting gamma-ray radiation produced by the scalaron decays. We will discuss initial conditions for the scalaron in the early universe and the role played by the Higgs field and electroweak crossover in the formation of these initial conditions.