In this short note we formulate Covariant Hamiltonian formalism for strings, p-branes and Non-BPS Dp-branes. We also analyse the vacuum tachyon condensation in case of unstable D1-brane.
We have found that kappa-symmetry allows a covariant quantization provided the ground state of the theory is strictly massive. For D-p-branes a Hamiltonian analysis is performed to explain the existence of a manifestly supersymmetric and Lorentz covariant description of the BPS states of the theory. The covariant quantization of the D-0-brane is presented as an example.
We discuss the covariant formulation of local field theories described by the Companion Lagrangian associated with p-branes. The covariantisation is shown to be useful for clarifying the geometrical meaning of the field equations and also their relation to the Hamilton-Jacobi formulation of the standard Dirac-Born-Infeld theory.
In this paper we derive the generalisations of Gauss-Codazzi, Raychaudhuri and area change equations for classical relativistic branes and multidimensional fluids in arbitrary background manifolds with metricity and torsion. The kinematical description we develop is fully covariant and based on the use of projection tensors tilted with respect to the brane worldsheets.
We develop a formalism that allows us to write actions for multiple D-branes with manifest general covariance. While the matrix coordinates of the D-branes have a complicated transformation law under coordinate transformations, we find that these may be promoted to (redundant) matrix fields on the transverse space with a simple covariant transformation law. Using these fields, we define a covariant distribution function (a matrix generalization of the delta function which describes the location of a single brane). The final actions take the form of an integral over the curved space of a scalar…
We construct the full effective action including DBI and WZ terms for solitonic 5-branes covariant under T-duality. The result is a completion of results known in the literature to a full T-duality covariant expression. The covariant WZ action includes previously omitted R-R terms. The obtained full covariant effective action reproduces the one obtained by S-duality from the D5-brane upon the correct choice of the covariant charge.
The component form of the equations of motion for the 5-brane in eleven-dimensions is derived from the superspace equations. These equations are fully covariant in six-dimensions. It is shown that double-dimensional reduction of the bosonic equations gives the equations of motion for a 4-brane in ten dimensions governed by the Born-Infeld action.
We discuss an open supermembrane theory on the maximally supersymmetric pp-wave background in eleven dimensions. The boundary surfaces of an open supermembrane are studied by using the covariant supermembrane theory. In particular, we find the configurations of M5-branes and 9-branes preserving a half of supersymmetries at the origin.
We argue that type II string theories contain unstable NS4 branes, which descend from a conjectured unstable M4 brane of M-theory. Assuming that an M2 brane can arise in M5 brane/anti-brane annihilation, the unstable M4 brane, and also an unstable M3 brane, must exist as sphalerons. We compare the tensions of the unstable NS4 branes, M4 brane, and related type II unstable D-branes, and present 11d supergravity solutions for unstable Mp branes for all p. We study the Z_2 gauge symmetry on the worldvolume of unstable branes, and argue that it can never be unbroken in the presence of lower brane …
We consider a supersymmetric extension of the SL(2;Z)-covariant D3-brane action proposed by Nurmagambetov, and prove its kappa-symmetry in an on-shell type-IIB supergravity background.
We determine a manifestly SL(2,Z)-covariant kappa-symmetric action for the type IIB (p,q) five-branes as a perturbative expansion in the world-volume field strengths within the framework where the brane tension is generated by a world-volume field. In this formulation the Lagrangian is expected to be polynomial; we construct the kappa-invariant action to fourth order in the world-volume field strengths.
We consider the open superstring action in the AdS$_4 \times \mathbf{CP}^3$ background and investigate the suitable boundary conditions for the open superstring describing the 1/2-BPS D-branes by imposing the $κ$-symmetry of the action. This results in the classification of 1/2-BPS D-branes from covariant open superstring. It is shown that the 1/2-BPS D-brane configurations are restricted considerably by the Kähler structure on $\mathbf{CP}^3$. We just consider D-branes without worldvolume fluxes.
We consider D-branes of open superstrings in the AdS_5 x S^5 background. The possible configurations of D-branes preserving half of supersymmetries are classified by analyzing the kappa-invariance of an open superstring in a covariant manner. We also revisit the classification of D-branes in the pp-wave background. It is shown that Penrose limits of the possible D-branes in the AdS_5 x S^5 give all of the D-branes in the pp-wave. In addition, 1/4 supersymmetric D-string, which is related to the D-string preserving 8 dynamical supersymmetries in the pp-wave, is presented. We also discuss the re…
A superspace formulation of IIB supergravity which includes the field strengths of the duals of the usual physical one, three and five-form field strengths as well as the eleven-form field strength is given. The superembedding formalism is used to construct kappa-symmetric SL(2,R) covariant D-brane actions in an arbitrary supergravity background.
We derive boundary conditions for the covariant open string corresponding to D-branes in an Hpp-wave, by requiring kappa symmetry of its bulk action. Both half-supersymmetric and quarter-supersymmetric branes are seen to arise in this way, and the analysis furthermore agrees fully with the existing probe brane and supergravity computations. We elaborate on the origin of dynamical and kinematical supersymmetries from the covariant point of view. In particular we focus on the D-string which only preserves half of the dynamical supersymmetries and none of the kinematical ones. We discuss its orig…
We briefly review a covariant analysis of D-branes of type IIB superstring on the AdS_5xS^5 background from the κ-invariance of the Green-Schwarz string action. The possible configurations of D-branes preserving half of supersymmetries are classified in both cases of AdS_5xS^5 and the pp-wave background.
Using a fully covariant formalism given by Carter for the deformation dynamics of p-branes governed by the Dirac-Nambu-Goto action in a curved background, it is proved that the corresponding Witten's phase space is endowed with a covariant symplectic structure, which can serve as a starting point for a phase space quantization of such objects. Some open questions for further research are outlined.
We explore noncommutative D-branes in the AdS_5xS^5 background from the viewpoint of κ-invariance of a covariant open string action in the Green-Schwarz formulation. Boundary conditions to ensure the κ-invariance of the action lead to possible configurations of noncommutative D-branes. With this covariant method, we derive configurations of 1/4 BPS noncommutative D-branes. The resulting D-branes other than D-string are 1/4 BPS at any places, and the D-string is exceptional and it is 1/2 BPS at the origin and 1/4 BPS outside the origin. All of them are reduced to possible 1/4 BPS or 1/2 BPS AdS…
We discuss an open supermembrane theory in the AdS_4 x S^7 and AdS_7 x S^4 backgrounds. The possible Dirichlet branes of an open supermembrane are classified by analyzing the covariant Wess-Zumino term. All of the allowed configurations are related to those on the pp-wave background via the Penrose limit.
Canonical forms are given for the nilpotent BRS operator $\d$ and the covariant `loop space' derivative ${\cal D}_{\m}$ for the p-brane fields for all odd p. The defining characteristic of ${\cal D}_{\m}$ is that it is a functional derivative operator which generalizes the ordinary functional derivative and also commutes with $\d$. Methods of construction for the canonical forms are discussed.
We give an explicit form of the PST-type SL(2;R)-covariant super D3-brane action for the flat Minkowski background. To this end, we follow the prescription developed by Hatsuda and Kamimura. As an application of the action, we obtain the supercharge of the action by using the standard Noether's method and calculate the Poisson bracket algebra of the supercharge. The central charge of the supersymmetry algebra is given in a manifestly SL(2;R)-covariant way.
We construct Spin(p+1,p+1) covariant Dp-brane bound states by using that the potentials in the RR sector of toroidically compactified type II supergravity transform as a chiral spinor of the T-duality group. As an application, we show the invariance of the zero-force condition for a probe D-brane under noncommutative deformations of the background, which gives a holographic proof of the stability of the corresponding field theory ground state under noncommutative deformations. We also identify the Spin(p+1,p+1) transformation laws by examining the covariance of the D-brane Lagrangians.
We work out boundary conditions for the covariant open string in the type IIA plane wave background, which corresponds to the D-branes in the type IIA theory. We use the kappa symmetric string action and see what kind of boundary conditions should be imposed to retain kappa symmetry. We find half BPS as well as quarter BPS branes and the analysis agrees with the previous work in the light cone gauge if the result is available. Finally we find that D0-brane is non-supersymmetric.
We study covariant open bosonic string field theories on multiple $Dp$-branes by using the deformed cubic string field theory which is equivalent to the string field theory in the proper-time gauge. Constructing the Fock space representations of the three-string vertex and the four-string vertex on multiple $Dp$-branes, we obtain the field theoretical effective action in the zero-slope limit. On the multiple $D0$-branes, the effective action reduces to the Banks-Fishler-Shenker-Susskind (BFSS) matrix model. We also discuss the relation between the open string field theory on multiple $D$-insta…
Exact holography for cosmological branes in an AdS-Schwarzschild bulk was first introduced in hep-th/0204218. We extend this notion to include all co-dimension one branes moving in non-trivial bulk spacetimes. We use a covariant approach, and show that the bulk Weyl tensor projected on to the brane can always be traded in for "holographic" energy-momentum on the brane. More precisely, a brane moving in a non-maximally symmetric bulk has exactly the same geometry as a brane moving in a maximally symmetric bulk, so long as we include the holographic fields on the brane. This correspondence is ex…
We discuss an open supermembrane in the presence of a constant three-form. The boundary conditions to ensure the kappa-invariance of the action lead to possible Dirichlet branes. It is shown that a noncommutative (NC) M5-brane is possible as a boundary and the self-duality condition that the flux on the world-volume satisfies is derived from the requirement of the kappa-symmetry. We also find that the open supermembrane can attach to each of infinitely many M2-branes on an M5-brane, namely a strong flux limit of the NC M5-brane.
For the kappa-symmetric super IIA D-brane action by the canonical approach we construct an equivalent effective action which is characterized by an auxiliary scalar field. By analyzing the canonical equations of motion for the kappa-symmetry-gauge-fixed action we find a suitable conformal-like covariant gauge fixing of reparametrization symmetry to obtain a simplified effective action where the non-linear square root structure is removed. We discuss how the two effective actions are connected.
We formulate p-brane Newton-Cartan background through the limiting procedure from relativistic Dirac-Born-Infeld action and Wess-Zumino term. We also determine action for unstable D(p+1)-brane in p-brane Newton-Cartan Background and study its properties.
We briefly review how to discuss noncommutative (NC) M5-branes and intersecting NC M5-branes from kappa-invariance of an open supermembrane action with constant three-form fluxes. The kappa-invariance gives rise to possible Dirichlet brane configurations. We shortly summarize a construction of projection operators for NC M5-branes and some intersecting configurations of NC M5-branes. A strong flux limit of them is also discussed.
We study the construction of covariant nonlinear duality-symmetric actions in dual formulation. Essentially, the construction is the PST-covariantisation and nonlinearisation of Zwanziger action. The covariantisation made use of three auxiliary scalar fields. Apart from these, the construction proceed in a similar way to that of the standard formulation. For example, the theories can be extended to include interactions with external fields, and that the theories possess two local PST symmetries. We then explicitly demonstrate the construction of covariant nonlinear duality-symmetric actions in…
We study intersecting noncommutative (NC) M5-branes from κ-invariance of an open supermembrane action with constant three-form fluxes. The $κ$-invariance gives rise to possible D-brane configurations for which projection operators can be determined. We construct projection operators for two types of 1/4 BPS intersecting NC M5-branes. The one is an intersection of two NC M5-branes: NC M5\bot NC M5 (3). The other is that of a NC M5-brane and a commutative (C) M5-brane: NC M5\bot C M5 (1). A NC M5-brane can be viewed as a bound state of M5 and M2, and the configurations M2\bot M5 (1) and M2\bot M…
The new first order, rheonomic, kappa-supersymmetric formalism recently introduced by us for the world-volume action of the D3-brane is extended to the case of D5-branes. This extension requires the dual formulation of the Free Differential Algebra of type IIB supergravity in terms of 6-form gauge potentials which was so far missing and is given here. Furthermore relying on our new approach we are able to write the D5-world volume action in a manifestly SL(2,R) covariant form. This is important in order to solve the outstanding problem of finding the appropriate boundary actions of D3-branes o…
We propose a method of determining masses in brane scenarios which is independent of coordinate transformations. We apply our method to the scenario of Randall and Sundrum (RS) with two branes, which provides a solution to the hierarchy problem. The core of our proposal is the use of covariant equations and expressing all coordinate quantities in terms of invariant distances. In the RS model we find that massive brane fields propagate proper distances inversely proportional to masses that are not exponentially suppressed. The hierarchy between the gravitational and weak interactions is neverth…
This paper is devoted to the construction of unstable D-brane action in torsional Newton-Cartan background through T-duality along null direction. We determine corresponding equations of motion and analyze their solution that corresponds to lower dimensional non-relativistic D(p-1)-brane. We also find Hamiltonian for unstable Dp-brane and study tachyon vacuum solutions that can be interpreted as gas of non-relativistic strings.
By using the non-supersymmetric $p$-brane solutions delocalized in arbitrary number of transverse directions in type II supergravities, we show how they can be regarded as interpolating solutions between unstable D$p$-branes (a non-BPS D-brane or a pair of coincident D-brane-antiD-brane) and fundamental strings and also between unstable D$p$-branes and NS5-branes. We also show that some of these solutions can be regarded as interpolating solutions between NS5/$\bar{\rm NS}$5 and D$p$-branes (for $p \leq 5$). This gives a closed string description of the tachyon condensation and lends support t…
In this paper we continue the study of non-relativistic p+1 dimensional theories that we started at arXiv:0904.1343. We extend the analysis presented there to the case of stable and unstable Dp-branes.
In the context of tachyon effective theory coupled to Born-Infeld electromagnetic fields, we obtain all possible singularity-free static flat configurations of codimension one on unstable Dp-branes. Computed tension and string charge density suggest that the obtained kinks are D(p-1) or D(p-1)F1-branes.
In this work, we extend a theory which describes a linearly self-dual exact 3-form field in six dimensional spacetime within the formalism of arXiv:1511.08220 and arXiv:1903.12196 to an action which fully describes an M5-brane in the eleven-dimensional supergravity background. The action we obtain has all the required symmetries including kappa-symmetry. Although the derivation of the action and the proof the symmetries do not require one to express the action explicitly in terms of the original field contents, we also give an initial attempt to give this expression.
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.
We propose a complete Born-Infeld-like action for a bosonic 5-brane with the worldvolume chiral field in a background of gravitational and antisymmetric gauge fields of D=11 supergravity. When the five-brane couples to a three-rank antisymmetric gauge field local worldvolume symmetries of the five-brane require the addition to the action of an appropriate Wess-Zumino term. To preserve general coordinate and Lorentz invariance of the model we introduce a single auxiliary scalar field. The auxiliary field can be eliminated by gauge fixing a corresponding local symmetry at the price of the loss o…
We consider the mirage cosmology by an unstable probe brane whose action is represented by BDI action with tachyon. We study how the presence of tachyon affects the evolution of the brane inflation. At the early stage of the brane inflation, the tachyon kinetic term can play an important role in curing the superluminal expansion in mirage cosmology.
The covariant quantization of massless D=11 superparticle (M0-brane) in its twistor-like Lorentz harmonic formulation is used to clarify the origin and some properties of the Berkovits pure spinor approach to quantum superstring and to search for hidden symmetries of D=11 supergravity. In the twistor like Lorentz harmonic formulation, the SO(16) symmetry is seen already at the classical level. The quantization produces the linearized supergravity multiplet as 128+128=256 component Majorana spinor of SO(16) and also shows an indirect argument in favor of the possible E8 symmetry.
We construct an action for unstable M3-brane in M-theory. We argue that in order to find M3-brane action that upon direct dimensional reduction leads to non-BPS D3-brane action in type IIA theory we have to presume that the background possesses Killing isometry and that this isometry has to be gauged on the world-volume of M3-brane. Then we construct singular tachyon kink on world-volume of M3-brane and we show that the dynamics of resulting topological defect is governed by an action that upon direct dimensional reduction leads to D2-brane in type IIA theory and that is equivalent to standard…
We construct Dp-branes in bosonic string theory as unstable lumps in a truncated string field theory of open strings on a D25-brane. We find that the lowest level truncation gives good quantitative agreement with the predicted D-brane tension and low-lying spectrum of the D-brane for sufficiently large p and study the effect of the next level corrections for p=24. We show that a U(1) gauge field zero mode on the D-brane arises through a mechanism reminiscent of the Randall-Sundrum mechanism for gravity.
We discuss various aspects of the description of branes as topological solitons in unstable brane systems of higher dimensions. We first describe a classification of all the possible realisations of branes of M and type II theories as topological solitons of a brane-antibrane system. We then present a description of type IIB NS-NS p-branes in terms of topological solitons in systems of spacetime-filling NS9, anti-NS9 pairs and discuss the implications of these constructions in the description of BPS and non-BPS states in the strongly coupled Heterotic SO(32) theory. We finally present briefly …
We construct unstable classical solutions of Yang-Mills theories and their dual unstable states of type IIB on AdS_5. An example is the unstable D0-brane of type IIB located at the center of AdS. This has a field theory dual which is a sphaleron in gauge theories on S^3 x R. We argue that the two are dual because both are sphalerons associated to the topology of the instanton/D-instanton. This agreement provides a non-supersymmetric test of the AdS/CFT duality. As an illustration, many aspects of Sen's hypothesis regarding the unstable branes can be seen easily in the weakly coupled dual field…
We study the geodesic motion of an unstable brane moving in a higher dimensional bulk spacetime. The tachyon which is coupled to a U(1) gauge field induces a non-trivial cosmological evolution. Interestingly enough, this system exhibits a much smoother initial cosmological singularity in comparison with former works.
We consider the polarization of unstable type IIB D0-branes in the presence of a background five-form field strength. This phenomenon is studied from the point of view of the leading terms in the non-abelian Born Infeld action of the unstable D0-branes. The equations have SO(4) invariant solutions describing a non-commutative 3-sphere, which becomes a classical 3-sphere in the large N limit. We discuss the interpretation of these solutions as spherical D3-branes. The tachyon plays a tantalizingly geometrical role in relating the fuzzy S^3 geometry to that of a fuzzy S^4.
Using the techniques of two dimensional conformal field theory we construct time dependent classical solutions in open string theory describing the decay of an unstable D-brane in the presence of background electric field, and explicitly evaluate the time dependence of the energy momentum tensor and the fundamental string charge density associated with this solution. The final decay product can be interpreted as a combination of stretched fundamental strings and tachyon matter.
We generalize the current algebra of constraints of U-duality-covariant critical superstrings to include the generator responsible for the dynamics of the fundamental brane. This allows us to define $κ$ symmetry and to write a worldvolume action in Hamiltonian form that is manifestly supersymmetric in the target space. The Lagrangian form of this action is generally covariant, but the worldvolume metric has fewer components than expected.
We study systems with a large number of meta-stable Dp-branes, and show that they describe Schwarzschild and Schwarzschild-like black branes, generalizing the results of Danielsson, Guijosa and Kruczenski. The systems are considered in both the open and closed string pictures. We identify the horizon size and its relation to the physics of open and closed strings. From the closed string perspective the region inside the horizon is where the effects of massive closed strings become important.
To exhibit the possible origin of the inner complexity of the Berkovits's pure spinor approach, we consider the covariant BRST quantization of the D=11 massless superparticle (M0-brane) in its spinor moving frame or twistor-like Lorentz harmonics formulation. The presence of additional twistor-like variables (spinor harmonics) allows us to separate covariantly the first and the second class constraints. After taking into account the second class constraints by means of Dirac brackets and after further reducing the first class constraints algebra, the dynamical system is described by the cohomo…
In six- and seven-dimensional gauged supergravity, each scalar potential has one supersymmetric and one non-supersymmetric fixed points. The non-supersymmetric $AdS_7$ fixed point is perturbatively unstable. On the other hand, the non-supersymmetric $AdS_6$ fixed point is known to be perturbatively stable. In this note we examine the newly proposed non-perturbative decay channel, called brane-jet instabilities of the $AdS_6$ and $AdS_7$ vacua. We find that when they are uplifted to massive type IIA and eleven-dimensional supergravity, respectively, the non-supersymmetric $AdS_6$ and $AdS_7$ va…
Dilaton gravity with general brane localized interactions is investigated. Models with corrections up to arbitrary order in field derivatives are considered. Effective gravitational equations of motion at the brane are derived in the covariant approach. Dependence of such brane equations on the bulk quantities is discussed. It is shown that the number of the bulk independent brane equations of motion depends strongly on the symmetries assumed for the model and for the background. Examples with two and four derivatives of the fields are presented in more detail.
We investigate the geometry of lightsheets comprised of null geodesics near a brane. Null geodesics which begin parallel to a brane a distance d away are typically gravitationally bound to the brane, so that the maximum distance from the geodesic to the brane never exceeds d. The geometry of resulting lightsheets is similar to that of the brane if one coarse grains over distances of order d. We discuss the implications for the covariant entropy bound applied to brane worlds.
Type I string theory provides eight classes of unstable D-brane systems. We determine the gauge group and tachyon spectrum for each one, and thereby describe the gauge symmetry breaking pattern in the low-energy world-volume field theory. The topologies of the resulting coset vacuum manifolds are related to the real K-theory groups KO^{-n}, extending the known relations between the Type II classifying spaces BU and U and the complex K-theory groups K^0 and K^{-1}. We also comment on the role of the background D9-branes.
We first review self-dual (chiral) gauge field theories by studying their Lorentz non-covariant and Lorentz covariant formulations. We next construct a non-Abelian self-dual two-form gauge theory in six dimensions with a spatial direction compactified on a circle. This model reduces to the Yang-Mills theory in five dimensions for a small compactified radius R. The model also reduces to the Lorentz-invariant Abelian self-dual two-form theory when the gauge group is Abelian. The model is expected to describe multiple 5-branes in M-theory. We also discuss its decompactified limit, covariant formu…