Representing the Graviton Self-Energy on de Sitter Background
  We derive a noncovariant but simple representation for the self-energy of a conformally transformed graviton field on the cosmological patch of de Sitter. Our representation involves four structure functions, as opposed to the two that would be necessary for a manifestly de Sitter invariant representation. We work out what the four structure functions are for the one loop correction due to a massless, minimally coupled scalar. And we employ the result to work out what happens to dynamical gravitons. 
Katie E. Leonard (Applied Mathematics), Sohyun Park (Penn State   University), Tomislav Prokopec (Utrecht University) and R....
gr-qc astro-ph.CO hep-th