Two applications of the infrared factorization of IR dynamics
Abstract:
I will review a proof of factorization of the dynamics of
infrared gravitons, that uses canonical transformations and is
particularly well suited to studying the evolution of local operators
in the Heisenberg picture. Working with operators instead of states,
makes it possible to define Lorentz transformations that commute with
infrared gravitons. If these transformations could be promoted to
proper unitary transformations on states, they would solve an old
"problem" in GR, that is the non uniqueness of the Lorentz group of
asymptotically flat spacetime. Canonical transformations can be also
defined in a collapse black-hole geometry. They will be used to
compute exactly the interaction of Hawking quanta with soft gravitons
in the limit that back-reaction on the metric can be neglected