Speaker
Ms
Nicola Rendell
(University of York)
Description
Our universe is believed to have experienced an inflationary period in its early stages of
development. It is therefore of interest to understand the behaviour of the graviton two point
function in an inflationary spacetime. We consider a background Friedman-Lemaitre-
Robertson-Walker (FLRW) spacetime, which is a (slow roll) inflationary spacetime. The
graviton two point function is known to be infrared divergent in such a spacetime. It has been
previously found, in de Sitter spacetime, that a large coordinate gauge transformation can be
used to remove the infrared divergence, and this suggests that the divergence should not
lead to local physical effects. The next natural step appeared to be to see if this type of
transformation could be used effectively in a FLRW spacetime. We found that this was
indeed the case, and removed the leading order divergence of the graviton two point
function. The correspondence between the gauge invariant part of the graviton two point
function and the linearized Weyl tensor correlator gives a bound on the extent to which the
divergence can be removed. This bound suggests that our transformation removes all
unphysical infrared divergence, without affecting the physical behaviour of the two point
function.
| What would be the preferred length of your talk? | 20 minutes + questions |
|---|
Primary author
Ms
Nicola Rendell
(University of York)
