State-to-state kinetics in the chemistry of the early Universe

The evolution of the early Universe between the end of the recombination era and the formation of the first large bodies was determined by a series of chemical processes. A review on the chemical networks will be presented, together with new results on a novel state-to-state approach, where non-LTE (local thermal equilibrium) features in the vibrational distribution of selected molecules (namely H2 and H2+) have been found. Non-equilibrium distributions and their direct and indirect effects on physical observables will be addressed.