Kea posted this on another thread: The Tomita-Takesaki results are and exciting breakthrough in AQFT, by now getting to be pretty well understood. The beginnings of it are in Haag's book Local Quantum Physics. Another line of work in AQFT that approaches the idea of matter in QG is represented by the work of Klaus Fredenhagen and his colleagues. A recent example is gr-qc/0603079, Towards a Background Independent Formulation of Perturbative Quantum Gravity, by Romeo Brunetti and Klaus Fredenhagen. A brief quotation will give the flavor.