Consistent closure of renormalization group flow equations in quantum gravity

Codello, Alessandro; D'Odorico, Giulio; Pagani, Carlo

doi:10.1103/physrevd.89.081701

Cited by 91 publications

(104 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, an extension of the truncation in a bimetric direction is possible as in quantum Einstein gravity [53][54][55][56][57][58][59][60] and seems indicated, see, e.g., [91]. This is possible both within pure gravity as well as including matter.…”

Section: Discussionmentioning

confidence: 99%

The Renormalization Group flow of unimodular f(R) gravity

Eichhorn

2015

J. High Energ. Phys.

125

101

View full text Add to dashboard Cite

Unimodular gravity is classically equivalent to General Relativity. This equivalence extends to actions which are functions of the curvature scalar. At the quantum level, the dynamics could differ. Most importantly, the cosmological constant is not a coupling in the unimodular action, providing a new vantage point from which to address the cosmological constant fine-tuning problem. Here, a quantum theory based on the asymptotic safety scenario is studied, and evidence for an interacting fixed point in unimodular f (R) gravity is found. We study the fixed point and its properties, and also discuss the compatibility of unimodular asymptotic safety with dynamical matter, finding evidence for its compatibility with the matter degrees of freedom of the Standard Model.

show abstract

Section: Discussionmentioning

confidence: 99%

The Renormalization Group flow of unimodular f(R) gravity

Eichhorn

2015

J. High Energ. Phys.

125

101

View full text Add to dashboard Cite

show abstract

“…Such propagator can be viewed as a two dimensional propagator hinting to a dimensional reduction phenomenon [21][22][23]. The computation of the anomalous dimension in the spirit mentioned above (leading to a propagator of the type p 4−η ) has been performed in very few truncations, see for instance [4,5,24].…”

Section: Scaling Arguments and Functional Renormalization Groupmentioning

confidence: 99%

“…The framework employed in these investigations involves the Effective Average Action (EAA) and its Renormalization Group (RG) [3]. In this setting, truncations of increasing complexity have been analyzed including bimetric ansätze, higher derivative terms and infinite dimensional truncations, see [4][5][6][7][8][9][10][11] for some of the most recent works.…”

Section: Introductionmentioning

confidence: 99%

Composite operators in asymptotic safety

Pagani

Reuter

2017

Phys. Rev. D

Self Cite

View full text Add to dashboard Cite

We study the role of composite operators in the Asymptotic Safety program for quantum gravity. By including in the effective average action an explicit dependence on new sources we are able to keep track of operators which do not belong to the exact theory space and/or are normally discarded in a truncation. Typical examples are geometric operators such as volumes, lengths, or geodesic distances. We show that this set-up allows to investigate the scaling properties of various interesting operators via a suitable exact renormalization group equation. We test our framework in several settings, including Quantum Einstein Gravity, the conformally reduced Einstein-Hilbert truncation, and two dimensional quantum gravity. Finally, we briefly argue that our construction paves the way to approach observables in the Asymptotic Safety program.

show abstract

“…More recently more sophisticated calculations have been performed by including additional terms in the action which have a non-trivial background field dependence [47][48][49][50]. The nature of these non-covariant terms are in principle constrained by (modified) BRST invariance [51].…”

Section: Rg For Gravity and Asymptotic Safetymentioning

confidence: 99%

“…In [52] the background field dependence of such terms has been evaluated via the Nielsen identities for the geometric effective action. Although in other works the modified BRST invariance of such approximations has not been determined, the flow of covariance breaking couplings such as mass parameters [49], wave function renormalisation [48,49] and purely background field couplings [47,50] has been assessed, while in [49] the flow of the full momentum dependent graviton propagator was evaluated. Additionally, the scale dependence…”

Section: Rg For Gravity and Asymptotic Safetymentioning

confidence: 99%

Asymptotic safety and the cosmological constant

Falls

2016

J. High Energ. Phys.

View full text Add to dashboard Cite

Abstract:We study the non-perturbative renormalisation of quantum gravity in four dimensions. Taking care to disentangle physical degrees of freedom, we observe the topological nature of conformal fluctuations arising from the functional measure. The resulting beta functions possess an asymptotically safe fixed point with a global phase structure leading to classical general relativity for positive, negative or vanishing cosmological constant. If only the conformal fluctuations are quantised we find an asymptotically safe fixed point predicting a vanishing cosmological constant on all scales. At this fixed point we reproduce the critical exponent, ν = 1/3, found in numerical lattice studies by Hamber. Returning to the full theory we find that by setting the cosmological constant to zero the critical exponent agrees with the conformally reduced theory. This suggests the fixed point may be physical while hinting at solution to the cosmological constant problem.

show abstract

Consistent closure of renormalization group flow equations in quantum gravity

Cited by 91 publications

References 49 publications

The Renormalization Group flow of unimodular f(R) gravity

The Renormalization Group flow of unimodular f(R) gravity

Composite operators in asymptotic safety

Asymptotic safety and the cosmological constant

Contact Info

Product

Resources

About