Dp-brane Action Research Articles

Canonical analysis of geometrical action for Dp-brane

In this short note we perform canonical analysis of geometrical action for Dp-brane. We also discuss tachyon condensation in case of the geometrical action for unstable D(p+1)-brane.

Gaugino condensation and geometry of the perfect square

Gaugino condensation plays a crucial role in the formation of de Sitter vacua. However, the theory of this effect is still incomplete. In four dimensions, the perfect square nature of gaugino couplings follows from the square of auxiliaries in the supergravity action. We explain here why the supersymmetric non-Abelian Dp-brane action, which is the basis for the theory of ten-dimensional gaugino condensation, must have a four-gaugino coupling. This term in the Einstein-Yang-Mills ten-dimensional supergravity is a part of the perfect square, mixing a 3-form with a gaugino bilinear. The perfect square term follows from the superspace geometry, being a square of the superspace torsion. The supercovariant equation of motion for a gaugino on the non-Abelian Dp-brane also involves a supertorsion in agreement with the perfect square term in the action.

Carroll limit of non-BPS Dp-brane

We find Carroll non-BPS Dp-brane action by performing Carroll limit of a canonical form of unstable Dp-brane action. We analyze different Carroll limits and discuss solutions of the equations of motion of Carroll non-BPS Dp-brane at the tachyon vacuum.

Note about unstable D-branes with dynamical tension

We propose an action for unstable Dp-brane with dynamical tension. We show that the equations of motion are equivalent to the equations of motion derived from DBI and WZ actions for non-BPS Dp-brane. We also find Hamiltonian formulation of this action and analyze properties of the solutions corresponding to the tachyon vacuum and zero tension solution.

Effective action for Dp-brane in large RR (p − 1)-form background

We construct the low energy effective action for the bosonic sector on a Dp-brane in large constant RR (p-1)-form field background. The action is invariant under both U(1) gauge symmetry and the volume-preserving diffeomorphism characterizing the RR-field background. Scalar fields representing transverse coordinates of the Dp-brane are included. It also respects T-duality and is consistent with the action for M5-brane in C-field background.

Four-derivative brane couplings from string amplitudes

We evaluate the string theory disc amplitude of one Ramond-Ramond field C^(p-3) and two Neveu-Schwarz B-fields in the presence of a single Dp-brane in type II string theory. From this amplitude we extract the four-derivative (or equivalently order (alpha')^2) part of the Dp-brane action involving these fields. We show that the new couplings are invariant under R-R and NS-NS gauge transformations and compatible with linear T-duality.

Coupling M2-branes to background fields

We discuss some of the issues arising in trying to extend the ABJM action to include couplings to background fields. This is analogous to the Myers-Chern-Simons terms of the multiple Dp-brane action. We review and extend previous results to include terms which are quadratic in the background fields. These are fixed by requiring that we recover the correct Myers-type terms upon using the novel Higgs mechanism to reduce to the multiple D2-brane action.

Dp-branes, NS5-branes and U-duality from nonabelian (2,0) theory with Lie 3-algebra

We derive the super Yang-Mills action of Dp-branes on a torus T^{p-4} from the nonabelian (2,0) theory with Lie 3-algebra. Our realization is based on Lie 3-algebra with pairs of Lorentzian metric generators. The resultant theory then has negative norm modes, but it results in a unitary theory by setting VEV's of these modes. This procedure corresponds to the torus compactification, therefore by taking a transformation which is equivalent to T-duality, the Dp-brane action is obtained. We also study type IIA/IIB NS5-brane and Kaluza-Klein monopole systems by taking other VEV assignments. Such various compactifications can be realized in the nonabelian (2,0) theory, since both longitudinal and transverse directions can be compactified, which is different from the BLG theory. We finally discuss U-duality among these branes, and show that most of the moduli parameters in U-duality group are recovered. Especially in D5-brane case, the whole U-duality relation is properly reproduced.

Aspects of U-duality in BLG models with Lorentzian metric 3-algebras

In [1], it was shown that BLG model based on a Lorentzian metric 3-algebra gives Dp-brane action whose worldvolume is compactified on torus Td (d = p−2). Here the 3-algebra was a generalized one with d+1 pairs of Lorentzian metric generators and expressed in terms of a loop algebra with central extensions. In this paper, we derive the precise relation of the coupling constant of the super Yang-Mills, the moduli of Td and some R-R flux to VEV's of ghost fields associated with Lorentzian metric generators. In particular, for d = 1, we derive the Yang-Mills action with θ term and show that SL(2,Z) Montonen-Olive duality is realized as the rotation of two VEV's. Furthermore, some moduli parameters such as NS-NS 2-form flux are identified as the deformation parameters of the 3-algebras. By combining them, we recover most of the moduli parameters which are required by U-duality symmetry.

Non relativistic Dpbranes

We construct a kappa-symmetric and diffeomorphism-invariant non-relativistic Dp-brane action as a non-relativistic limit of a relativistic Dp-brane action in flat space. In a suitable gauge the world-volume theory is given by a supersymmetric free field theory in flat spacetime in p+1 dimensions of bosons, fermions and gauge fields.

Stability of D1-Strings Inside a D3-Brane

Within the tachyon condensation approach, we find that a D(p-2)-brane is stable inside Dp-branes when the bulk is compactified. It is a codimension-2 soliton of the Dp-brane action with coupling to the bulk (p-1)-form RR field. We discuss the properties of such solitons. They may appear as detectable cosmic strings in our universe.

Bosonic D-brane Effective Action in Linear Dilaton Background

In this paper we will study tachyon effective action for Dp-brane in bosonic string theory in the linear dilaton background. We obtain the tachyon effective Lagrangian from boundary state coeficient of Dp-brane in the linear dilaton background and compare it with tachyon effective Lagrangians that were proposed in previous papers.

Fermions, T-duality and effective actions for D-branes in bosonic backgrounds

We find the effective action for any D-brane in a general bosonic background of supergravity. The results are explicit in component fields up to second order in the fermions and are obtained in a covariant manner. No interaction terms between fermions and the field $f=b+F$, characteristic of the bosonic actions, are considered. These are reserved for future work. In order to obtain the actions, we reduce directly from the M2-brane world-volume action to the D2-brane world-volume action. Then, by means of T-duality, we obtain the other Dp-brane actions. The resulting Dp-brane actions can be written in a single compact and elegant expression.

DUALITY PROPERTIES OF SUPER D-BRANE ACTIONS IN GENERAL TYPE IIB SUPERGRAVITY BACKGROUND

We examine duality transformations of supersymmetric and κ-symmetric Dp-brane actions in a general type IIB supergravity background where in particular the dilaton and the axion are not supposed to be zero or a constant but a general superfield. Due to nonconstant dilaton and axion, we can explicitly show that the dilaton and the axion as well as the two two-form gauge potentials transform as doublets under the SL (2,R) transformation from the point of view of the world volume field theory.

Dual D-brane actions

Dual super Dp-brane actions are constructed by carrying out a duality transformation of the world-volume U(1) gauge field. The resulting world-volume actions, which contain a ( p - 2)-form gauge field, are shown to have the expected properties. Specifically, the D1-brane and D3-brane transform in ways that can be understood on the basis of the SL(2, Z) duality of type IIB superstring theory. Also, the D2-brane and the D4-brane transform in ways that are expected on the basis of the relationship between type IIA superstring theory and 11D M-theory. For example, the dual D4-brane action is shown to coincide with the double-dimensional reduction of the recently constructed M5-brane action. The implications for gauge-fixed D-brane actions are discussed briefly.