How Does Particle Scattering Work in Loop Quantum Gravity?

[wolram]

http://arxiv.org/PS_cache/gr-qc/pdf/0502/0502036.pdf
Particle scattering in loop quantum gravity
Leonardo Modesto and Carlo Rovelli
Centre de Physique Th´eorique de Luminy, Universit´e de la M´editerran´ee, F-13288 Marseille, EU
(February 9, 2005)
We devise a technique for defining and computing n-point functions in the context of a background-
independent gravitational quantum field theory. We construct a tentative implementation of this technique in a perturbatively-finite loop/spinfoam model.
---------------------------------------------------------------------------
Came across this by accident, its way over my head, but i guess if you
have not already read it imay be of interest.

 

[marcus]

http://arxiv.org/PS_cache/gr-qc/pdf/0502/0502036.pdf
Particle scattering in loop quantum gravity
Leonardo Modesto and Carlo Rovelli
...

I am glad you spotted this. I hadnt noted it so I just now added it to the collection of LQG links. the abstract page is
http://arxiv.org/gr-qc/0502036

it is always good to keep track of what Rovelli is doing, he tends to go at the heart of problems, so even if he has not yet gotten conclusive results a short paper like this can show us what he thinks is a hard place or a "sticking place" that needs concerted effort

Modesto is a postdoc who I think was doing string theory until a couple of years ago and then moved from Torino to Marseille and took up doing quantum gravity. He wrote something about eliminating the black hole singularity last year.

 

[R0man]

Thank you for sharing this paper on particle scattering in loop quantum gravity. It is indeed a complex and technical topic, but one that is of great interest in the field of quantum gravity. Loop quantum gravity (LQG) is a theoretical framework that seeks to reconcile general relativity with quantum mechanics, and it is still an active area of research with many open questions.

The paper you shared discusses a technique for defining and computing n-point functions in a background-independent gravitational quantum field theory. This is important because in LQG, the concept of a fixed background spacetime is abandoned, and instead, spacetime is seen as a dynamically evolving network of interconnected loops. This makes it challenging to define traditional scattering amplitudes, which are typically based on a fixed background.

The authors propose a way to overcome this challenge by using a perturbatively-finite loop/spinfoam model. This involves breaking down the calculation into smaller, more manageable pieces and then summing them together to obtain the full scattering amplitude. This is a promising approach and could lead to a better understanding of particle scattering in LQG.

Overall, this paper contributes to the ongoing research in loop quantum gravity and provides valuable insights into the challenges and potential solutions for defining and computing particle scattering in this framework. Thank you for sharing this interesting and thought-provoking piece of work.