p–p System with B field, branes at angles and noncommutative geometry

T-duality and actions for noncommutative D-branes

“…As discussed in [18,20], D-branes at angles could become unstable and behave as D −D systems. It would be very interesting to have a complete discussion of these phenomena.…”

“…As discussed in [18,19,20,21,22], there are two things which happen: the T 2 torus gets deformed and the D8 branes is rotated in the (x 1 , x 2 ) plane. If we consider a T-duality along the x 2 direction, we obtain a torus with a rotation of the x 2 axis into an x ′2 axis by an angle π/2 − α given by:…”

“…We consider non-commutative D-branes wrapped on tori with different dimensions and we check the transformation of their actions under T-dualities with respect to different directions on the tori. We use the results of [17,18,19,20,21,22] concerning the effect of T-duality on the noncommutative D-branes. The results is that, after T-duality, a noncommutative D-brane becomes a commutative D-brane rotated with respect to the original coordinates of the torus and the torus itself becomes deformed.…”

p−p′ system with B field and projection operator noncommutative solitons

“…In the superstring case, these modes generate a tower of light states which survives the zero slope limit [8] [22]. This implies that in the low energy physics Dp-brane is perturbatively seen as a collection of such a large number of light states.…”

A D2-brane realization of Maxwell-Chern-Simons-Higgs systems

“…Although N = (8, 0) supersymmetry is realized in this case, the three-dimensional Poincaré invariance is broken [12]. In [13] open string spectra and BPS conditions of Dp-Dp ′ systems are studied and it is pointed out that Dp-D(p + 6) systems can be made BPS by turning on a constant B-field. Recently, Mihailescu, Park and Tran [14] and Witten [15] take advantage of this fact to study gauge theories on D-branes.…”