Early Universe cosmology with mirror dark matter
  Mirror matter is a stable self-collisional dark matter candidate. If exact
mirror parity is a conserved symmetry of nature, there could exist a parallel
hidden (mirror) sector of the Universe which has the same kind of particles and
the same physical laws of our (visible) sector. The two sectors interact each
other predominantly via gravity, therefore mirror matter is naturally "dark".
Here I briefly review the cosmological signatures of mirror dark matter, as Big
Bang nucleosynthesis, primordial structure formation and evolution, cosmic
microwave background and large scale structure power spectra, together with its
compatibility with the interpretation of the DAMA annual modulation signal in
terms of photon--mirror-photon kinetic mixing. Summarizing the present status
of research and comparing theoretical results with observations/experiments, it
emerges that mirror matter is not just a viable, but a promising dark matter
candidate.
