We evaluate the phase diagram of quantum gravity within a fully diffeomorphism-invariant renormalisation group approach. The construction is based on the geometrical or Vilkovisky-DeWitt effective action. We also resolve the difference between the fluctuation metric and the background metric. This allows for fully background-independent flows in gravity.The results provide further evidence for the ultraviolet fixed point scenario in quantum gravity with quantitative changes for the fixed point physics. We also find a stable infrared fixed point related to classical Einstein gravity. Implications and possible extensions are discussed.

We analysed how teachers as users of open educational resources (OER) repositories act in the re-use process and how they perceive quality. Based on a quantitative empirical study, we also surveyed which quality requirements users have and how they would contribute to the quality process. Trust in resources, organizations, and technologies seem to be of particular importance when looking at quality. In our findings, we derive recommendations for learning object repositories and OER user-oriented quality assurance.

Abstract

We put forward a continuum approach for computing finite temperature correlation functions in Yang-Mills theory. This is done in a functional renormalisation group setting which allows for the construction of purely thermal RG-flows. This approach is applied to the ghost and gluon propagators as well as the ghost-gluon vertex in the Landau gauge. We present results in a temperature regime going from vanishing temperature to temperatures far above the confinement-deconfinement temperature Tc. Our findings compare well with the lattice results available.

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