6533b855fe1ef96bd12afefb

RESEARCH PRODUCT

Scale-dependent metric and causal structures in Quantum Einstein Gravity

Jan-markus SchwindtMartin Reuter

subject

High Energy Physics - TheoryPhysicsNuclear and High Energy PhysicsScale (ratio)SpacetimeAsymptotic safety in quantum gravityFOS: Physical sciencesGeneral Relativity and Quantum Cosmology (gr-qc)General Relativity and Quantum CosmologyAction (physics)Causality (physics)Theoretical physicssymbols.namesakeHigh Energy Physics - Theory (hep-th)Metric (mathematics)symbolsEinsteinQuantum

description

Within the asymptotic safety scenario for gravity various conceptual issues related to the scale dependence of the metric are analyzed. The running effective field equations implied by the effective average action of Quantum Einstein Gravity (QEG) and the resulting families of resolution dependent metrics are discussed. The status of scale dependent vs. scale independent diffeomorphisms is clarified, and the difference between isometries implemented by scale dependent and independent Killing vectors is explained. A concept of scale dependent causality is proposed and illustrated by various simple examples. The possibility of assigning an "intrinsic length" to objects in a QEG spacetime is also discussed.

https://doi.org/10.1088/1126-6708/2007/01/049