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<record version="1" id="317">
 <title>quantum Riemannian geometry</title>
 <name>QuantumRiemannianGeometry</name>
 <created>2008-10-19 23:36:26</created>
 <modified>2008-10-19 23:36:26</modified>
 <type>Topic</type>
 <creator id="441" name="bci1"/>
 <modifier id="441" name="bci1"/>
 <comment>quantum gravity theories, non-commutative geometry, non-Abelian geometry, non-Abelian topology, noncommutative topology</comment>
 <author id="441" name="bci1"/>
 <classification>
	<category scheme="msc" code="03.65.Pm"/>
 </classification>
 <defines>
	<concept>a mathematical approach to quantum gravity based on noncommutative geometry/noncommutative operator algebra</concept>
 </defines>
 <synonyms>
	<synonym concept="quantum Riemannian geometry" alias="Non-Commutative Geometry"/>
	<synonym concept="quantum Riemannian geometry" alias="Non-Abelian Geometry"/>
	<synonym concept="quantum Riemannian geometry" alias="Non-Abelian Topology"/>
	<synonym concept="quantum Riemannian geometry" alias="Noncommutative Topology"/>
 </synonyms>
 <keywords>
	<term>Quantum Gravity Theories</term>
	<term>Non-Commutative Geometry</term>
	<term>Non-Abelian Geometry</term>
	<term>Non-Abelian Topology</term>
	<term>Noncommutative Topology</term>
 </keywords>
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 <content>\textbf{Description:} 
\emph{Quantum geometry (or quantum geometries)} is an approach (resp. are approaches) to Quantum Gravity that are based on either noncommutative geometry and SUSY (the `Standard' Model of current Physics) \cite{AC94,CA85} or
modified or `deformed' Riemannian, `quantum' geometry, with additional assumptions regarding a generalized `Dirac' operator, the `spectral triplet' with non-Abelian structures of quantized space-times. 


\textbf{Remarks.}
Other approaches to Quantum Gravity include: Loop Quantum Gravity (LQG), AQFT approaches,
Topological Quantum Field Theory (TQFT)/ Homotopy Quantum Field Theories (HQFT; Tureaev and Porter, 2005),
Quantum Theories on a Lattice (QTL), string theories and spin network models. \\

An interesting, but perhaps limiting approach, involves \emph{`quantum' Riemannian geometry} \cite{AL2k5} in place of the classical Riemannian manifold that is employed in the well-known, Einstein's classical approach to General Relativity (GR). 

\begin{thebibliography}{9}
\bibitem{AC94}
A. Connes. 1994. \emph{Noncommutative Geometry}. Academic Press: New York and London.

\bibitem{CA85}
Connes, A. 1985 .Non-commutative differential geometry I--II. 
\emph{Publication Math\'ematiques IHES}, {\bf 62}, 41--144.
 
\bibitem{AL2k5}
Abhay Ashtekar and Jerzy Lewandowski. 2005. Quantum Geometry and Its Applications.
\PMlinkexternal{Available PDF download}{http://cgpg.gravity.psu.edu/people/Ashtekar/articles/qgfinal.pdf}.
\end{thebibliography}</content>
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