Long-distance properties of baryons in the Sakai-Sugimoto model
  We reconsider the realization of baryons in the Sakai-Sugimoto model. In this theory, which is the gravity dual of a QCD-like theory, baryons appear as soliton solutions. These solitons were approximated as flat-space instantons in previous studies. However, with this approximation, it has been shown that one does not reproduce some model-independent predictions for the behavior of baryon electromagnetic form factors which are connected with long-range pion physics. This made it appear that the long-range pion physics of baryons may be hidden in (intractable) \alpha' corrections in the gravity dual. In this paper, we study the long-range properties of baryons in the Sakai-Sugimoto model without relying on the flat-space instanton approximation. The solution we obtain gives the correct result for the model-independent ratio of form factors, implying that the model captures the expected infrared properties of baryons without the need to go beyond the leading order in the \alpha' expansion. 
Aleksey Cherman, Takaaki Ishii
hep-th hep-ph nucl-th