6533b837fe1ef96bd12a29d8
RESEARCH PRODUCT
Cosmology of the Planck Era from a Renormalization Group for Quantum Gravity
Martin ReuterAlfio Bonannosubject
PhysicsInflation (cosmology)High Energy Physics - TheoryNuclear and High Energy PhysicsAstrophysics (astro-ph)FOS: Physical sciencesHierarchy problemGeneral Relativity and Quantum Cosmology (gr-qc)Cosmological constantAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysicsGeneral Relativity and Quantum CosmologyGeneral Relativity and Quantum CosmologyClassical mechanicsHigh Energy Physics - Theory (hep-th)Planck timeQuantum cosmologyFlatness problemMathematical physicsPlanck lengthLoop quantum cosmologydescription
Homogeneous and isotropic cosmologies of the Planck era before the classical Einstein equations become valid are studied taking quantum gravitational effects into account. The cosmological evolution equations are renormalization group improved by including the scale dependence of Newton's constant and of the cosmological constant as it is given by the flow equation of the effective average action for gravity. It is argued that the Planck regime can be treated reliably in this framework because gravity is found to become asymptotically free at short distances. The epoch immediately after the initial singularity of the Universe is described by an attractor solution of the improved equations which is a direct manifestation of an ultraviolet attractive renormalization group fixed point. It is shown that quantum gravity effects in the very early Universe might provide a resolution to the horizon and flatness problem of standard cosmology, and could generate a scale-free spectrum of primordial density fluctuations.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2001-06-15 |