I heard that Fay Dowker (Imperial College London) is scheduled to give a series of introductory lectures on CS-quantum gravity at Perimeter in October. They've been posting video of talks like this on PIRSA fairly consistently. So I expect Dowker's talks will be online--a short introductory video textbook. Joe Henson just gave a one hour introduction to Dowker's introduction Henson is a postdoc at Perimeter who is an expert in the CS approach and also works in CDT (causal dynamical triangulations). One thing he has done recently is develop supercomputer or cluster tools for numerical QG work---including CDT simulations but also something called "Cactus CausalSets". Cactus is a system for distributed computing. I thought Henson's brief one hour talk on the CS essentials was good. A place to start if you want to follow Dowker's talks later---or a clear summary of CS if that's all you want. The video is on PIRSA http://pirsa.org/10090092 An invitation to an invitation to causal sets Joe Henson 14 September 2010 "A brief review of some recent work on the causal set approach to quantum gravity. Causal sets are a discretisation of spacetime that allow the symmetries of GR to be preserved in the continuum approximation. One proposed application of causal sets is to use them as the histories in a quantum sum-over-histories, i.e. to construct a quantum theory of spacetime. It is expected by many that quantum gravity will introduce some kind of fuzziness uncertainty and perhaps discreteness into spacetime, and generic effects of this fuzziness are currently being sought. Applied as a model of discrete spacetime, causal sets can be used to construct simple phenomenological models which allow us to understand some of the consequences of this general expectation."