Everything everywhere all at once
The extragalactic background light is the modern twist to Olbers’ paradox and represents all the radiation produced since recombination. Over the past few years, direct, indirect and very high energy measurements appear to have converged giving what seems to be a consistent picture. If correct this implies that by far the majority of all energy production occurs within discrete sources, i.e., galaxies. Hence encoded in the EBL (extragalactic background light) is the entire history of galaxy formation and evolution with the main photon production pathways being dominated by star-formation, AGN activity and dust reprocessing. By measuring and modelling the EBL to a few-% accuracy, we appear to be able to provide a clear description of energy production in the Universe from Ultraviolet to radio wavelengths in all redshift slices. The talk will cover the development of our measurements, the construction of our phenomenological model, and future directions.