Jackiw–Teitelboim gravity

In theoretical physics, Jackiw–Teitelboim gravity, also known as JT gravity or the R=T model, is a theory of gravity with a dilaton in one spatial and one time dimension (1+1D). It was first formulated by Roman Jackiw and Claudio Teitelboim.

Source: Wikipedia — Jackiw–Teitelboim gravity (CC BY-SA 4.0)