Renate Loll: Really nonperturbative quantum gravity

I will sketch the toolbox and achievements of modern lattice quantum gravity, aka solving the full 4D Lorentzian gravitational path integral, using causal dynamical triangulations (CDT). It provides us with a long-sought window on physics in a near-Planckian regime, where geometry is highly nonclassical and not describable in terms of standard tensor calculus. With concrete answers to longstanding issues of how to properly implement diffeomorphism invariance, causal structure and Wick rotation, we are now focusing on interesting, approach-independent questions on the nature of nonperturbative quantum gravity and its observables. Based on results on the dynamical emergence of a 4D universe with de Sitter properties from first principles, early-universe cosmology may be our best bet in terms of quantum gravity phenomenology. ---------------------------------------------------------------------------------------------------------- For announcements of upcoming seminars you can visit http://www.qiss.fr/virtual-seminars.html or join our mailing list through https://groups.google.com/forum/#!for.... ---------------------------------------------------------------------------------------------------------- About QISS The Quantum Information Structure of Spacetime (http://www.qiss.fr) is an interdisciplinary research initiative among several universities and research institutes all over the world, supported by the John Templeton Foundation through the grants https://www.templeton.org/grant/the-q... and https://www.templeton.org/grant/the-q..., coordinated from The Samy Maroun Center for Space, Time and the Quantum (http://www.spacetimeandquantum.com). The goal of QISS is to explore and connect the research domains of Quantum Information/Computing, Quantum Gravity and Quantum Foundations. Main objectives are to found the physics of quantum spacetime on an information-theoretic basis, to bring within reach empirical access to quantum gravity in 'table-top' laboratory conditions by exploiting rapid advances in quantum computing related technologies and using quantum information theoretic concepts, and to promote an extensive interaction between physicists and philosophers on the conceptual role of information in spacetime physics.