Programme

Speaker: Johannes Brunnemann
Title: Singularities in LQG: A Status Report
Abstract: Loop Quantum Cosmology (LQC) has taken huge steps towards an answer to the question about sigularity (dis-)appearence in a quantum theory of gravity. The results look very promising, however they are usually obtained within the framework of symmetry reduced and thus simplified models. Although the construction of these models follows as close as possible the full theory of Loop Quantum Gravity (LQG), less is known about the influence of the symmetry reduction on the outcome of calculations and the validity of the symmetry assumptions, especially when it comes to the question of the occurrence of singularities. In order to strengthen the statements of LQC it is therefore of utmost interest to study cosmological situations within the full theory. The ideal picture would be an emergence of LQC results as certain limits of LQG calculations. In order to achieve this goal one has to consider both: reduced models under more relaxed symmetry assumptions within LQC and somewhat restricted calcualtions within the full theory of LQG. Recently first steps have been made to start the latter analysis. After a short comparison of LQC and LQG we will present the results obtained in [gr-qc/0505032, gr-qc/0505033] and give a status report on current investigations.
Talk: Transparencies, Recorded Talk