From initial-state fluctuations to final-state observables

This talk begins with the interpretation of the azimuthally collimated di-hadron correlation with large rapidity separations observed in heavy-ion and high multiplicity proton-proton collisions known as the “ridge”. The physics of the ridge is intimately related to quantum fluctuations responsible for the decoherence of the strongly occupied initial classical fields generated in heavyion collisions. Progress made in the implementation of a program to resum these instabilities and the connection with the final-state observables is discussed.