Physics of the very early universe: what can we learn from cosmological observations?

Cosmological observations are starting to probe the evolution of the Universe before nucleosynthesis. The observed fluctuations in the cosmic microwave background and in the distribution of matter can be traced back to their origin during inflation, and the inflaton potential has begun to be unraveled. A future probe of the first microseconds would be the detection of weakly-interacting massive particles as dark matter. Discovery of supersymmetric particles at odds with the standard cosmological lore may open an experimental window on the physics at the highest energies, perhaps as far as superstring theory. This presentation will overview two topics on the physics of the Universe before nucleosynthesis: (1) slow-roll, natural and chain inflation in the landscape, and (2) neutralino dark matter production from inflatons or moduli fields.