Cosmology
  Cosmology and particle physics are deeply interrelated. Among the common
problems are dark energy, dark matter and baryon asymmetry of the Universe. We
discuss these problems in general terms, and concentrate on several particular
hypotheses. On the dark matter side, we consider weakly interacting massive
particles and axions/axion-like particles as cold dark matter, sterile
neutrinos and gravitinos as warm dark matter. On the baryon asymmetry side, we
discuss electroweak baryogenesis as a still-viable mechanism. We briefly
describe diverse experimental and observational approaches towards checking
these hypotheses. We then turn to the earliest cosmology. We give arguments
showing that the hot stage was preceded by another epoch at which density
perturbations and possibly primordial gravity waves were generated. The best
guess here is inflation, which is consistent with everything we know of density
perturbations, but there are alternative scenarios. Future measurements of the
properties of density perturbations and possible discovery of primordial
gravity waves have strong potential in this regard.
