Abstract
We present a general framework to systematically study the derivative expansion of asymptotically safe quantum gravity. It is based on an exact decoupling and cancellation of different modes in the Landau limit, and implements a correct mode count as well as a regularisation based on geometrical considerations. It is applicable independent of the truncation order. To illustrate the power of the framework, we discuss the quartic order of the derivative expansion and its fixed point structure as well as physical implications.
Highlights
We provide a solution to the problem of regularisation in asymptotically safe quantum gravity motivated by geometrical arguments
The idea is based on the observation that if we were to compute the propagator in flat spacetime, that is to zeroth order in the derivative expansion, we can go to momentum space and perform the inversion with standard techniques
Since the commutator increases the order of the expression by at least one derivative, the recursive application of (102) produces only finitely many terms for a fixed order of the derivative expansion
Summary
One of the major open problems in fundamental physics is the formulation of a consistent quantum theory of gravity. In the context of gravity, this corresponds to powers of curvature tensors and their covariant derivatives To this point a complete non-perturbative discussion of the fourth order approximation has not been carried out in the context of Asymptotic Safety. We provide a solution to the problem of regularisation in asymptotically safe quantum gravity motivated by geometrical arguments It is based on the decomposition into gauge variant and invariant components of the field, and can be applied to any order of the derivative expansion, including resummations in terms of form factors. We compute the complete non-perturbative renormalisation group running in quantum gravity to fourth order in the derivative expansion.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
