Two dimensional nearly de Sitter gravity

A bstract We study some aspects of the de Sitter version Jackiw-Teitelboim gravity. Though we do not have propagating gravitons, a boundary mode when compute observables with fixed dilaton and metric at boundary. no-boundary wavefunctions probability measures to all orders in perturbation theory. also discuss contributions from different topologies, borrowing recent results by Saad, Shenker Stanford. how leads gravitational corrections cosmological add matter. Finally, starting four dimensional gravity theory positive constant, consider nearly extremal black hole argue that are dominated two dynamics.