The D2-D6 System and a Fibered AdS Geometry
Abstract
Description
The system of D2 branes localized on or near D6 branes is considered. The world-volume theory on the D2 branes is investigated, using its conjectured relation to the near-horizon geometry. The results are in agreement with known facts and expectations for the corresponding field theory and a rich phase structure is obtained as a function of the energy scale and the number of branes. In particular, for an intermediate range of the number of D6 branes, the IR geometry is that of an AdS_4 space fibered over a compact space. This D2-D6 system is compared to other systems, related to it by compactification and duality and it is shown that the qualitative differences have compatible explanations in the geometric and field-theoretic descriptions. Another system -- that of NS5 branes located at D6 branes -- is also briefly studied, leading to a similar phase structure.
35 pages (Latex) and 2 figures (encapsulated postscript). Ver2: added discussion of the relation to the system without D6 branes (in the introduction and in figure 1); added description of the geometrical realization of the R symmetries (in section 3.1)
35 pages (Latex) and 2 figures (encapsulated postscript). Ver2: added discussion of the relation to the system without D6 branes (in the introduction and in figure 1); added description of the geometrical realization of the R symmetries (in section 3.1)