The many faces of brane-flux annihilation

Abstract

Fluxes can decay via the nucleation of Brown-Teitelboim bubbles, but when the decaying fluxes induce D-brane charges this process must be accompanied with an annihilation of D-branes. This occurs via dynamics inside the bubble wall as was well described for D3 branes annihilating against 3-form fluxes. In this paper we extend this to the other Dp branes with p smaller than seven. Generically there are two decay channels: one for the RR flux and one for the NSNS flux. The RR channel is accompanied by brane annihilation that can be understood from the Dp branes polarising into D(p + 2) branes, whereas the NSNS channel corresponds to Dp branes polarising into NS5 branes or KK5 branes. We illustrate this with the decay of antibranes probing local toroidal throat geometries obtained from T-duality of the D6 solution in massive type IIA. We show that Dp branes are metastable against annihilation in these backgrounds, at least at the probe level.

Unstoppable brane-flux decay of D 6 ¯ $$ \overline{\mathrm{D}6} $$ branes

“…For that we must first establish the metastability of D6-branes at the probe level which has not appeared in the literature before (see however [15]). We then indeed find that backreaction destabilises the D6 branes.…”

“…A second feature-crucial for this paper-is that the annihilation of the H 3 -flux does not proceed via a polarisation into a higher-dimensional object. All Dk branes with k < 6 polarise into an NS5 branes [15]. D6 branes instead polarise into KK5 branes, which are smaller in dimension.…”

“…Fluxes can decay against the p D6-charges in two ways [15]: 1) either by having a D8 brane polarising and move all the way over the S 3 which decreases the Romans mass or 2) by having a KK5 brane moving inside the D6 worldvolume which decreases the H 3 -flux. In this paper we focus on the second channel.…”

“…We must identify branes that can carry the D6-charge away, similar to the spherical NS5-brane in KPV [1]. These turn out to be KK5-branes that source D6-charge on their worldvolume [15]. This may seem strange as the KK5 is a 5-brane whereas the D6 is a 6-brane, but the KK5 has one special transverse direction, the NUT direction, which assumes circular isometry.…”

“…It is however technically easier to work in the T-dual frame, and use that the probe potentials are invariant under T-duality [15]. The T-dual setup involves a pair of probe NS5-branes, with opposite charge in the geometry Mink 6 × S 1 × M 3 where M 3 is the space transversal to the original 6-brane and is conformal to R 3 .…”