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**Causal Dynamic Triangulations**

Thanks Marcus, I have not been following this thread close enoughmarcus said:Yes Rybo, quantum gravity is what we are talking about in this thread. CDT is a newer approach to quantum gravity.

CDT means causal dynamical triangulations

it is a way of implementing a quantum version of Einstein 1915 classical theory of General Relativity. Other approaches tend to do this using a differentiable manifold to represent spacetime but CDT does not. It uses approximation by PL manifolds (also called simplicial manifolds)

the einstein action is implemented without using coordinates.

here is a short CDT paper that could serve as an introduction

http://arxiv.org/hep-th/0404156 [Broken]

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Quantum Graivity is the topic indeed ( Rybo-duhhh :).

I did go to the link you gave and read and saved the PDF document and now have good intro into Causal Dynamical Triangulations. (1) Why are triangulations more significant than squares or other polygons ergo the title CDT?

Most of the mathematics disscussed here are way above my head, HOWEVER, I do like to skim, pick and choose what goes well with my Synergetic interpretations and extrapolations thereof.

(2) Does CDT interpret( may be ) or require( is ) the physcial universe as being macro-finite? Here below is quote from PDF introduction to CDT.

..."This leads us to conclude that we have observed the emergence of a four-dimensional macroscopic world with three-dimensional spatial geometries. Judging from the computer simulations, this dynamically generated quantum geometry acts as a background geometry around which small quantum fluctuations take place. Further numerical studies will be needed to make this into a quantitative statement. The situation is really rather remarkable: we started out from an explicitly background-independent formalism and have rederived a particular stable background geometry.".......

Rybo

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