Description
Primordial black holes (PBHs) are a compelling dark matter candidate,
but their origin is still unclear. In this talk, I will present a scenario where PBHs are
produced from curvature perturbations sourced by primordial magnetic fields
generated in the early universe. The setup naturally explains both the observed
large-scale magnetic fields and the formation of PBHs in a mass range compatible
with the full dark matter abundance. I will show that this requires a reheating
temperature of 10^{5}–5\times10^{5}\,\mathrm{GeV}. The model also predicts a
secondary gravitational-wave background from magnetic anisotropies, with signals
potentially detectable by LISA, DECIGO, BBO, and SKA. This provides a testable
connection between magnetogenesis, PBH formation, and upcoming GW
observations.
