What is the interaction between quantum fields and Rovelli's particulate space of loop quantum gravity?

Question

I've read Rovelli's book and papers, but he makes little mention of quantum fields.  What is the interaction between fields and his particulate space of loop quantum gravity?  I know that he says loop quantum gravity "is space", so would fields then ride above that and be "in space".  I'm thinking of space as a bowl full of salt, and then a field as being jello poured into the bowl and filling up the gaps?

Prof. Legolasov · Answer

LQG is a specific flavor of the quantization procedure applied to General Relativity.  You can apply the same procedure to a system of GR coupled to matter fields.  You won't get a QFT in the usual sense, because there's no global Poincare invariance, because space-time is dynamical.  But there will be a sector in the theory that will closely resemble QFT particles on the Minkowski background interacting with each other, and with weak gravity.
Unlike string theory, LQG doesn't attempt to unify matter and gravity – just to consistently quantize a coupled system.  Though there have been proposals on how quantum fields / particles may originate from quantum aspects of LQG's geometry (noiseless subsystems), however, those proposals are highly speculative and unsuccessful.
Rovelli actually quantizes GR + matter systems in his books, and there's plenty of material on the subject on arxiv, too.

What is the interaction between quantum fields and Rovelli's particulate space of loop quantum gravity?

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