2014/08/01 by Kevin Falls · 38 citations
Mathematics · Physics and Astronomy · #Asymptotic safety in quantum gravity #Black Holes and Theoretical Physics #Conformal map #Constant (computer programming) #Cosmological constant #Cosmology and Gravitation Theories #Critical exponent #Critical point (mathematics) #Fixed point #General relativity #Infrared fixed point #Mathematical analysis #Mathematical physics #Mathematics #Noncommutative and Quantum Gravity Theories #Phase transition #Physics #Quantum #Quantum gravity #Quantum mechanics #Relationship between string theory and quantum field theory #Renormalization group #Theoretical physics #Ultraviolet fixed point #gr-qc #hep-th
paper · pdf · doi:10.1007/jhep01(2016)069
published in Journal of High Energy Physics 2016(1) (Springer Nature) · 34 pages, 9 figures
arxiv created 2014/08/01 · openalex publication_date 2016/01/01 · arxiv updated 2016/04/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
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.