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't Hooft anomalies, continuity, and anomaly inflow in gauge theories

't Hooft anomalies are indispensable tool that can shed light on the infrared spectrum of strongly-coupled theories. In this talk I will report on a newly discovered type of discrete mixed 't Hooft anomalies between 0-form and 1-form symmetries. Then, I use the anomaly matching conditions to propose a novel realization of the symmetries of SU(2) Yang-Mills theory with two massless adjoint Weyl fermions, QCD(adj), in the strongly-coupled regime. I will argue that this theory has a spectrum identical to the one obtained by compactifying it on a small spacial circle. Next, I discuss domain walls (DW) in hot QCD(adj) and show that the DW worldvolume theory in the SU(2) case is an axial version of the 2-charge Schwinger model. The DW admits a 1-form Z_{2} center and 0-form Z_{4} discrete chiral symmetries. Both of these symmetries are broken in the IR such that the mixed 't Hooft anomaly is saturated by a topological quantum field theory, as required by anomaly inflow arguments. I will also discuss how this picture is generalized to SU(N) and the parallels one can draw between DW in hot QCD(adj) and strings in QCD(adj) on a small spacial circle.