How QIT Arguments Rely on Symmetry

In quantum information theory (QIT), arguments often rely — sometimes implicitly — on the assumption that a given process can be repeated identically and independently many times. However, establishing the stochastic independence of repeated processes from physical principles is challenging. The quantum de Finetti theorem offers a solution by deriving stochastic independence from symmetry principles. In my talk, I will review the quantum de Finetti theorem and discuss its use in QIT arguments, with a particular focus on the black hole information puzzle.