arXiv subjects

C. A. Ballon Bayona

Publications and source records attributed to C. A. Ballon Bayona.

22 records · Page 2Linked to original sources

arXiv2008

Deep inelastic scattering from gauge string duality in the soft wall model

Deep inelastic structure functions have been calculated by Polchinski and Strassler in gauge/string duality introducing a hard infrared (IR) cut off in AdS space. Here we investigate this problem using a soft IR cut off that leads to linear Regge trajectories for mesons. We calculate the structure functions for scalar particles in the large x regime where supergravity approximation holds and the small x regime where massive string states contribute. We also propose a hybrid model to calculate structure functions for fermions in the supergravity approximation. In the deep inelastic limit our results are in agreement with those obtained using a hard cut off.

hep-th↗

arXiv2008

Deep inelastic structure functions from supergravity at small x

Deep inelastic structure functions can be calculated from supergravity when the Bjorken parameter $x$ satisfies $ x > 1/\sqrt{gN} $. We consider a gauge theory with very large 't Hooft coupling $gN$ in order to investigate the region $x << 1$. In this case the center of mass energy is large enough to increase the number of hadronic constituents of the final state. We calculate the structure functions in terms of the number of final hadronic constituents. At small $x$ we find a scaling law similar to geometric scaling but with $γ_s = 0.5 $ and $ λ= 1 $.

hep-th↗

arXiv2008

On a Holographic Model for Confinement/Deconfinement

We study the thermodynamics of the hard wall model, which consists in the introduction of an infrared cut-off in asymptotically AdS spaces. This is a toy model for confining backgrounds in the context of the gauge/gravity correspondence. We use holographic renormalization and reproduce the existence of a Hawking Page phase transition recently discussed by Herzog. We also show that the entropy jumps from $N^0$ to $N^2$, which reinforces the interpretation of this transition as the gravity dual of confinement/deconfinement. We also show that similar results hold for the phenomenologically motivated soft wall model, underlining the potential universality of our analysis.

hep-th↗

arXiv2007

Anti-de Sitter boundary in Poincare coordinates

We study the space-time boundary of a Poincare patch of Anti-de Sitter (AdS) space. We map the Poincare AdS boundary to the global coordinate chart and show why this boundary is not equivalent to the global AdS boundary. The Poincare AdS boundary is shown to contain points of the bulk of the entire AdS space. The Euclidean AdS space is also discussed. In this case one can define a semi-global chart that divides the AdS space in the same way as the corresponding Euclidean Poincare chart.

hep-th↗