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arivero has http://www.physcomments.org/node/444" the considerable interest the physics community is showing into the new, or revived, field of Ads/QFT model building. It is somewhat similar to Lisa Randall's style of model building, described in her new book Warped Passages, which I recommend.
arivero only mentions by name one of the papers fueling the excitement, but I followed it up on the arxiv; it's hep-ph/0501128,
QCD and Holographic Model of Hadrons
By Joshua Erlich, Emanuel Katz, Dam T. Son, and Mikhail A. Stephanov
From the Abstract
From the introduction
From the Discussion and Outlook
One of the things I liked about this model is that it doesn't require supersymmetry; it just does QCD as we know it (slightly simplified). Do go and look at their tables of fits. Of course the point is not that they can tune a model to fit the data; it is that THIS model, though parsimonious, can be so tuned. It deserves the excited attention it is getting!
arivero only mentions by name one of the papers fueling the excitement, but I followed it up on the arxiv; it's hep-ph/0501128,
QCD and Holographic Model of Hadrons
By Joshua Erlich, Emanuel Katz, Dam T. Son, and Mikhail A. Stephanov
From the Abstract
We propose a five-dimensional framework for modeling low-energy properties of QCD. In the simplest three parameter model we compute masses, decay rates and couplings of the lightest mesons.
The model fits experimental data to within 10%. The framework is a holographic version of the QCD sum rules, motivated by the anti-de Sitter/conformal field theory (AdS/CFT) correspondence. The model naturally incorporates properties of QCD dictated by chiral symmetry, which we demonstrate by deriving the Gell-Mann–Oakes–Renner relationship for the pion mass.
From the introduction
Inspired by the gravity/gauge duality we propose the
following complementary approach. Rather than deform
the SYM theory to obtain QCD [5], we start from QCD
and attempt to construct its five-dimensional (5D) holo-
graphic dual. In this Letter, we present an exploratory
study of a simple holographic model of QCD. The field
content of the 5D theory is chosen to reproduce holo-
graphically the dynamics of chiral symmetry breaking in
QCD, the boundary theory. The model has four free pa-
rameters, one of which is fixed by the number of colors;
the remaining three parameters can be fitted using three
well-measured observables, e.g., the ρ meson mass, the
pion mass, and the pion decay constant. The model then
predicts other low-energy hadronic observables with sur-
prisingly good accuracy.
From the Discussion and Outlook
The holographic model of
QCD studied here is quite crude and depends on only
three free parameters, but it agrees surprisingly well with
the seven experimentally measured observables which we
have studied.
One of the things I liked about this model is that it doesn't require supersymmetry; it just does QCD as we know it (slightly simplified). Do go and look at their tables of fits. Of course the point is not that they can tune a model to fit the data; it is that THIS model, though parsimonious, can be so tuned. It deserves the excited attention it is getting!
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