Speaker
Description
Assuming a conformal phase of the early universe, we discuss the conformal backreaction, by studying the anomaly effective action around flat space and, in parallel, the anomaly induced actions (Fradkin Vilkovisly and Riegert's actions ) in curved space. Gravity is treated classically. Anomalies included take the form both of conformal (parity-even) and of chiral (parity odd) contributions. Crucial, in these derivations, is the possibility of solving the conformal Ward identities using CFT methods in momentum space for correlators of many-gravitons. We show how the identities allow to reconstruct the action in a consistent way up to 4-point functions perturbatively. The method defines a powerful way to patch flat and curved spacetime derivations. In this framework dark energy is attributed to the trace anomaly.
