28,588 research outputs found
Saturation and Confinement: Analyticity, Unitarity and AdS/CFT Correspondence
In expansion, analyticity and crossing lead to crossing even and odd
() vacuum exchanges at high-energy, the {\em Pomeron} and the {\em
Odderon}. We discuss how, using {\em String/Gauge duality}, these can be
identified with a reggeized {\em Graviton} and the anti-symmetric {\em
Kalb-Ramond fields} in background. With confinement, these Regge
singularities interpolate with glueball states. We also discuss unitarization
based on eikonal sum in .Comment: more references added. presented at ISMD 2008, 15-20 Sept. 200
Magnetic monopole loop for the Yang-Mills instanton
We investigate 't Hooft-Mandelstam monopoles in QCD in the presence of a
single classical instanton configuration. The solution to the Maximal Abelian
projection is found to be a circular monopole trajectory with radius
centered on the instanton. At zero loop radius, there is a marginally stable
(or flat) direction for loop formation to . We argue that loops
will form, in the semi-classical limit, due to small perturbations such as the
dipole interaction between instanton anti-instanton pairs. As the instanton gas
becomes a liquid, the percolation of the monopole loops may therefore provide a
semi-classical precursor to the confinement mechanism.Comment: 19 pages, ReVTeX, 5 Encaptulated Postscript figure
On the Eikonal Approximation in AdS Space
We explore the eikonal approximation to graviton exchange in AdS_5 space, as
relevant to scattering in gauge theories. We restrict ourselves to the regime
where conformal invariance of the dual gauge theory holds, and to large 't
Hooft coupling where the computation involves pure gravity. We give a heuristic
argument, a direct loop computation, and a shock wave derivation. The scalar
propagator in AdS_3 plays a key role, indicating that even at strong coupling,
two-dimensional conformal invariance controls high-energy four-dimensional
gauge-theory scattering.Comment: 22 pages, 2 figures; published version: updated references and
several clarifying remarks adde
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