Pro [Earman 2003]: most important for present purposes: makes GR amenable to quantization procedure.

Main disadvantage [Maudlin 2002]: “metaphysical monstrosities”, esp regarding recasting GR in Hamiltonian formalism. 

(D Schroeren’s cell phone rings]

LQG meant to be conservative approach, and can be considered a family of theories.  Large parts of what follows covered in papers one can find on CW’s personal website

Loop Q Grav:

Presentation is meant to be a review or instructive, and not novel research.Two major problems to be discussed: [1] problem of time and [2] dissolution/re-emergence of S-T

E Crull here.  First time blogger, long time listener.

We can apply all this to spin foams / spin nets!

The key question is this. Is there a phase which leads to smooth space times?

Some promising results! Dittrich & collaborators have found fix points from which one could extract different systems of embedding maps. Those would correspond to different (non-) realisations of ’emergence of space-time).

Task for the future: Expand the theory around this vacuum!

Coming back to the initial question: What is (quantum) space-time? Dittrich suggests the time scales for constructing an answer are ~2500ys. Challenge accepted!

Now moving from 1+1D to 2D!

How do we get a vacuum of a statistical system? Dittrich has the answer.

More boxes. Lots more boxes!