Breathing mode sphere reductions to two dimensions^*

Abstract Motivated by connections to AdS 2 holography and Jackiw–Teitelboim (JT) gravity, we consider general breathing mode reductions to two-dimensional dilaton gravity coupled to scalar matter. For small fluctuations around the vacuum, the matter decouples, and we recover JT gravity. We also extend the breathing mode reduction to higher-derivative Einstein–Maxwell theory, which yields a generalized dilaton gravity theory upon compactification.