Abstract :
Most galaxies in the universe spend their lives inhabiting what is called the main-sequence (MS) of star-formation, a relatively peaceful state in which galaxies form stars and feed their central massive black holes (BHs) in a steady manner. However, both simulations and observations suggest that, at least once within their life-times, galaxies undergo a merger event during which their star formation efficiencies and BH accretion rates drastically increase over a short period of time. This phase in galaxy evolution occurs behind a thick blanket of gas and dust that obscures the very luminous, central power source(s), and it is fundamental to our understanding of the main physical processes that drive the evolution of galaxies over cosmic time. In this talk I will present results obtained from infrared observations of nearby and high-redshift luminous infrared galaxies, for which in-depth studies of their interstellar medium have been only recently made possible by the advent of state-of-the-art telescope facilities such as Herschel, ALMA, and now JWST.
