Why not unify LQG with Superstring\M theory ?

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The discussion centers on the potential unification of Loop Quantum Gravity (LQG) with Superstring/M Theory, suggesting that such a merger could be feasible based on existing research. Key links between Quantum Field Theory (QFT) and string theory are highlighted, particularly through concepts like AdS/CFT duality. Notable papers by Thomas Thiemann and others propose methods for integrating LQG techniques with string theory, emphasizing the importance of background independence. However, there is skepticism regarding the necessity of unification, as it may lead to the loss of unique features inherent to both theories. The conversation encourages examining authors' motivations in their research to understand the implications of such unification efforts.
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Is it possible to unify both theories ? I think it may be possible
 
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Some ideas are in http://arxiv.org/abs/0907.2994

QFT -> spinnetworks

We also know of links between QFT and string theory in what is called AdS/CFT or gauge/gravity duality.
 
thank you very much
 
Here is an early (2004) attempt
http://arxiv.org/abs/hep-th/0401172
The LQG -- String: Loop Quantum Gravity Quantization of String Theory I. Flat Target Space
Thomas Thiemann
(Submitted on 23 Jan 2004)
"We combine I. background independent Loop Quantum Gravity (LQG) quantization techniques, II. the mathematically rigorous framework of Algebraic Quantum Field Theory (AQFT) and III. the theory of integrable systems resulting in the invariant Pohlmeyer Charges in order to set up the general representation theory (superselection theory) for the closed bosonic quantum string on flat target space. ..."
 
You can find several other papers by looking for those which cite the 2004 Thiemann.

It is not obvious why one would WANT to "unify LQG with SMT". One might lose valuable/interesting features of both. So it makes sense, when reading the papers, to look for each author's stated motivation---what they hope to achieve.

Here is a more recent (2009) paper of this sort, iook on page 2 of the PDF:
http://arxiv.org/abs/0908.0953

==quote page 2 of Fairbairn Noui Sardelli==
A few years ago, Thiemann [15] reconsidered the Nambu-Goto string and proposed a quantisation of it using the techniques of loop quantum gravity (LQG) [16]. He showed that the LQG techniques, based on background independent quantisation, provides in particular a quantisation of the bosonic string in any dimensions, i.e., there is no need of critical dimensions for the quantum theory to be consistent. This result has sparked off some discussions [17] and certainly deserves to be understood deeper. We think that the algebraic formulation of the bosonic string is a better starting point to test the LQG techniques than the Nambu-Goto string for it admits a lot of similarities with the Ashtekar-Immirzi-Barbero-Holst formulation [18], [19] of general relativity. It is a first order formulation and possesses an Immirzi-type parameter. In fact, the main motivation of this article is to open an arena for a background independent quantisation of the bosonic string and to compare it to the standard Fock quantisation. Our goal is to pursue the line of research initiated by Thiemann in the context of the algebraic formulation of strings.
==endquote==

I bolded what I think is the gist, to make it more visible.
 
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marcus said:
It is not obvious why one would WANT to "unify LQG with SMT". One might lose valuable/interesting features of both. So it makes sense, when reading the papers, to look for each author's stated motivation---what they hope to achieve.

Smolin is another one that worked hard on these matters. A few years ago he gave a long list of such papers:

http://golem.ph.utexas.edu/~distler/blog/archives/000855.html#c003826

Pay attention at the end of it.

"For attempts to use LQG methods to discover the background independent formulation of string and M theory:

http://arxiv.org/abs/hep-th/0002009 :
Title: M theory as a matrix extension of Chern-Simons theory
Authors: Lee Smolin
Comments: Latex, 17 pages, no figures
Journal-ref: Nucl.Phys. B591 (2000) 227-242

http://arxiv.org/abs/hep-th/0104050 :
Title: The exceptional Jordan algebra and the matrix string
Authors: Lee Smolin
Comments: LaTex 15 pages, no figures
Subj-class: High Energy Physics - Theory; Quantum Algebra

http://arxiv.org/abs/hep-th/0006137 [abs, ps, pdf, other] :
Title: The cubic matrix model and a duality between strings and loops
Authors: Lee Smolin
Comments: Latex, 32 pages, 7 figures
Subj-class: High Energy Physics - Theory; Quantum Algebra

http://arxiv.org/abs/hep-th/9712148 :
Title: Nonperturbative dynamics for abstract (p,q) string networks
Authors: Fotini Markopoulou, Lee Smolin
Comments: Latex, 12 pages, epsfig, 7 figures, min"
 
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