Quantum corrections to the gravitational backreaction

Abstract

Effective field theory techniques are used to study the leading order quantum corrections to the gravitational wave backreaction. The effective stress-energy tensor is calculated and it is shown that it has a non-vanishing trace that contributes to the cosmological constant. By comparing the result obtained with LIGO's data, the first bound on the amplitude of the massive mode is found: < 1.4×10 −33 .

Gravitational radiation in infinite derivative gravity and connections to effective quantum gravity

“…There is a second order effect where gravity couples to itself and produces a backreaction. In [36], the backreaction was found for Effective Quantum Gravity (EQG). EQG has a similar action to IDG (the F i ( ) in (1) are replaced by a i + b i log( /μ 2 ) where μ is a mass scale [37][38][39].…”

“…Since then, LIGO has found more stringent constraints of Ω 0 < 5.58 × 10 −8 [54]. Following the same method as [36], we divide by the critical density ρ c =…”

Spacetime instability due to quantum gravity

“…Observe that the d'Alembert operator ḡ is exactly the Laplace-Beltrami operator that acts on scalar fields even though it is being applied to a tensor field [25][26][27][28]. Although this is evident in the conformal patch (16) complemented with the gauge conditions (17), it is useful to change the coordinates to an FLRW-like chart to make contact with cosmology:…”

“…It is the behavior of h µν that will tell us about the spacetime stability. After linearization, the equation of motion obtained from (1) is [17] F ( ḡ )h µν = 0,…”

Exorcising ghosts in quantum gravity

“…An example of analytic F includes the polynomial function F (z) = N n=0 c n z n . On the other hand, an instance of a non-analytic generalized wave operator can be given by F (z) = (1 − α log(z))z, which appears when one-loop corrections to general relativity are considered[40].…”