Multifractional Spacetimes, Asymptotic Safety and HOŘAVA-LIFSHITZ Gravity
Abstract
We compare the recently formulated multifractional spacetimes with field theories of quantum gravity based on the renormalization group (RG), such as asymptotic safety and Hořava-Lifshitz gravity. The change of spacetime dimensionality with the probed scale is realized in both cases by an adaptation of the measurement tools ("rods") to the scale, but in different ways. In the multifractional case, by an adaptation of the position-space measure, which can be encoded into an explicit scale dependence of effective coordinates. In the case of RG-based theories, by an adaptation of the momenta. The two pictures are mapped into each other, thus presenting the fractal structure of spacetime in RG-based theories under an alternative perspective.
- Publication:
-
International Journal of Modern Physics A
- Pub Date:
- July 2013
- DOI:
- 10.1142/S0217751X13500929
- arXiv:
- arXiv:1209.4376
- Bibcode:
- 2013IJMPA..2850092C
- Keywords:
-
- Models of quantum gravity;
- renormalization group;
- fractal geometry;
- 04.60.-m;
- 05.45.Df;
- 11.10.Gh;
- 11.10.Kk;
- Quantum gravity;
- Fractals;
- Renormalization;
- Field theories in dimensions other than four;
- High Energy Physics - Theory;
- General Relativity and Quantum Cosmology
- E-Print:
- 21 pages, 1 table. v2: discussion improved, references added