We study the dynamical behavior of a pair of Dp-brane and anti Dp-brane ($0 \leq p \leq 6$) moving parallel to each other in the region where the brane and anti-brane annihilation will not occur and the low energy description is valid. Given this, we perform a general analysis, in the center of mass frame, of the behavior of the effective potential with respect to the relative brane separation and find that the classical orbits of this system are in general unbound except for $p = 6$ case for which classical bound orbits exist. The non-linearity of the low energy DBI action for D-brane is important for the underlying dynamics. We solve also the explicit orbits for $p = 6$ case.
We attempt to generalize the effective action for the D-brane-anti-D-brane system obtained from boundary superstring field theory (BSFT) by adding an extra D-brane to it to obtain a covariantized action for 2 D-branes and 1 anti-D-brane. We discuss the approximations made to obtain the effective action in closed form. Among other properties, this effective action admits solitonic solutions of codimension 2 (vortices) when one of the D-brane is far separated from the brane-anti-brane pair.
We propose a manifestly SO(8) invariant BF type Lagrangian for describing the dynamics of M2-brane-anti-M2-brane system in flat spacetime. When one of the scalars which satisfies a free-scalar equation takes a large expectation value, the M2-brane-anti-M2-brane action reduces to the tachyon DBI action of D2-brane-anti-D2-brane system in flat spacetime.
We propose an action for the D0-brane anti-D0-brane system that has its exact solution corresponding to the marginal tachyon profile defined for arbitrary constant separation of these D-branes. We also find its covariant formulation and generalization to higher dimensional Dp-branes.
In this short note we present analysis of the tachyon kink solution in the canonical formalism. We also find Hamiltonian for simplified system of Dp-brane and anti-Dp-brane.
We show that in the context of topological string theories N branes and M anti-branes give rise to Chern-Simons gauge theory with the gauge supergroup $U(N|M)$. We also identify a deformation of the theory which corresponds to brane/anti-brane annihilation. Furthermore we show that when $N=M$ all open string states are BRST trivial in the deformed theory.
It has been conjectured that the vortex solution on a D-brane - anti-D-brane system represents a D-brane of two lower dimension. We establish this result by first identifying a series of marginal deformations which create the vortex - antivortex pair on the brane - antibrane system, and then showing that under this series of marginal deformations the original D-brane - anti-D-brane system becomes a D-brane - anti-D-brane system with two lower dimensions. Generalization of this construction to the case of solitons of higher codimension is also discussed.
We develop the quasi-particle picture for Schwarzchild and far from extremal black holes. We show that the thermalization equations of the black hole is recovered from the model of branes and anti-branes. This can also be viewed as a field theory explanation of the relationship between area and entropy for these black holes. As a by product the annihilation rate of branes and anti-branes is computed.
The time-varying density of D-branes and anti-D-branes in an expanding universe is calculated. The D-brane anti-brane annihilation rate is shown to be too small to compete with the expansion rate of a FRW type universe and the branes over-close the universe. This brane problem is analogous to the old monopole problem. Interestingly however, it is shown that small dimension D-branes annihilate more slowly than high dimension branes. Hence, an initially brany universe may be filled with only low dimension branes at late times. When combined with an appropriate late inflationary theory this leads…
We present an improved effective action for the D-brane-anti-D-brane system obtained from boundary superstring field theory. Although the action looks highly non-trivial, it has simple explicit multi-vortex (i.e. codimension-2 multi-BPS D-brane) multi-anti-vortex solutions. The solutions have a curious degeneracy corresponding to different ``magnetic'' fluxes at the core of each vortex. We also generalize the brane anti-brane effective action that is suitable for the study of the inflationary scenario and the production of defects in the early universe. We show that when a brane and anti-brane…
In a tachyon effective field theory of a non-BPS brane, we construct a classical solution representing a parallel brane-antibrane. The solution is made of a kink and an antikink placed at antipodal points of S^1. Estimation of the brane energy suggests an excitation of a string connecting the two branes, even though the theory is Abelian. We performed fluctuation analysis around the obtained solution, and find the structure of the supersymmetry breaking by the co-existence of the brane and the antibrane. We discuss possible processes of the pair-annihilation of the brane defect.
We derive the perturbative four-dimensional effective theory describing heterotic M-theory with branes and anti-branes in the bulk space. The back-reaction of both the branes and anti-branes is explicitly included. To first order in the heterotic strong-coupling expansion, we find that the forces on branes and anti-branes vanish and that the KKLT procedure of simply adding to the supersymmetric theory the probe approximation to the energy density of the anti-brane reproduces the correct potential. However, there are additional non-supersymmetric corrections to the gauge-kinetic functions and m…
Recently, some authors have considered the quantum spectrum of black holes . This consideration is extended to tachyonic black holes in a brane-anti-brane system. In this study, black holes are constructed from two branes which are connected by a tachyonic tube. As the branes come closer to each other, they evolve and make a transition to thermal black branes. It will be shown that the spectrum of these black holes depends on the tachonic potential and the separation distance between the branes. By decreasing the separation distance, more energy emerges and the spectrum of the black hole incre…
We investigate the static solutions of Callan and Maldecena and Gibbons to lowest order Dirac-Born-Infeld theory. Among them are charged wormhole solutions connecting branes to anti-branes. It is seen that there are no such solutions when the separation between the brane and anti-brane is smaller than some minimum value. The minimum distance coincides with the energy minimum, and depends monotonically on the charge. Making the charge sufficiently large, such that the minimum separation is much bigger than $ \sqrt{α'}$, may suppress known quantum processes leading to decay of the brane-anti-bra…
We describe a tachyon-free stable non-BPS brane configuration in type IIA string theory. The configuration is an elliptic model involving rotated NS5 branes, D4 branes and anti-D4 branes, and is dual to a fractional brane-antibrane pair placed at a conifold singularity. This configuration exhibits an interesting behaviour as we vary the radius of the compact direction. Below a critical radius the D4 and anti-D4 branes are aligned, but as the radius increases above the critical value the potential between them develops a minimum away from zero. This signals a phase transition to a configuration…
We study the dynamics of anti-M2 branes in a warped Stenzel solution with M2 charges dissolved in fluxes by taking into account their full backreaction on the geometry. The resulting supergravity solution has a singular magnetic four-form flux in the near-brane region. We examine the possible resolution of this singularity via the polarization of anti-M2 branes into M5 branes, and compute the corresponding polarization potential for branes smeared on the finite-size four-sphere at the tip of the Stenzel space. We find that the potential has no minimum. We then use the potential for smeared bra…
Anti-D-branes inserted in warped throat geometries (supported by fluxes that carry D-brane charges) develop unphysical singularities. It has been argued that these singularities could be resolved when one goes beyond the linearized approximation or includes the effects of brane polarization. In this paper we consider anti-D6 branes, whose singularities have been shown to exist at the full non-linear level, and demonstrate that there is no D8 brane polarization that can resolve the singularity. We comment on the potential implications of this result for the resolution of anti-D3 brane singulari…
Crossing symmetry appears in Dbrane-anti-Dbrane dynamics in the form of an analytic continuation from U(N) for N brane amplitudes to U(N-p,p) for the interactions of N-p branes with p anti-branes. I consider the consequences for supersymmetry and brane-anti-brane forces.
An exact solution, in which a D2-brane and an anti-D2-brane are connected by an elliptically tubular D2-brane, is obtained without any junction condition. The solution is shown to preserve one quarter of the supersymmetries of the type-IIA Minkowski vacuum. We show that the configuration cannot be obtained by "blowing-up" from some inhomogeneously D0-charged superstrings. The BPS bound tells us that it is rather composed of D0-charged D2-brane-anti-D2-brane pair and a strip of superstrings connecting them. We obtain the correction to the charges of the string end points in the constant magneti…
We consider the Penrose limit of the solution of D5-brane given in the Anti-de Sitter space and analyse the shape of the D5-brane in the pp-wave background. We find that the D5-brane leads to the branes and the throats connecting the branes. The branes spread on R^4 with periodic values of the light-cone time x^+ and the throats lie along x^+. We also give some comments on holography.
In this paper we point out the inevitability of an explosive production of gauge field and gravity wave during an open string tachyon condensation in a cosmological setting. We will be particularly studying an example of brane-anti-brane inflation in a warped throat where inflation ends via tachyon condensation. We point out that a tachyonic instability helps fragmenting the homogeneous tachyon and excites gauge field and contributes to the stress energy tensor which also feeds into the gravity waves.
We argue that the early universe may be described by an initial state of space-filling branes and anti-branes. At high temperature this system is stable. At low temperature tachyons appear and lead to a phase transition, dynamics, and the creation of D-branes. These branes are cosmologically produced in a generic fashion by the Kibble mechanism. From an entropic point of view, the formation of lower dimensional branes is preferred and $D3$ brane-worlds are exponentially more likely to form than higher dimensional branes. Virtually any brane configuration can be created from such phase transiti…
A coincident D-brane - anti-D-brane pair has a tachyonic mode. We present an argument showing that at the classical minimum of the tachyonic potential the negative energy density associated with the potential exactly cancels the sum of the tension of the brane and the anti-brane, thereby giving a configuration of zero energy density and restoring space-time supersymmetry.
We compute the imaginary self-dual (ISD) and imaginary anti-self-dual (IASD) fluxes for the Klebanov-Strassler background perturbed by a stack of p anti-D3 branes. We show that, at linear order in p, they both have a singularity in the near-brane region. While one can argue that the IASD flux may disappear at full non-linear level, no such argument exists for the ISD mode. An analogy with anti-D6 backreaction suggests that such singularity may survive once full backreaction is taken into account and may be a universal feature of anti-brane solutions.
We suggest a duality invariant formula for the entropy and temperature of non-extreme black holes in supersymmetric string theory. The entropy is given in terms of the duality invariant parameter of the deviation from extremality and 56 SU(8) covariant central charges. It interpolates between the entropies of Schwarzschild solution and extremal solutions with various amount of unbroken supersymmetries and therefore serves for classification of black holes in supersymmetric string theories. We introduce the second auxiliary 56 via E(7) symmetric constraint. The symmetric and antisymmetric combi…
We examine the proposal for constructing the effective action of a D-brane-anti-D-brane system from the non-abelian extension of tachyon DBI action. We consider two prescriptions for the trace in the non-abelian tachyon DBI action. The usual trace and the symmetric trace prescription. The former gives an action for the D\bar{D} system which reduces to the action proposed by A.Sen for coincident branes. The latter gives a different action which is consistent with the S-matrix element calculations.
We improve on the understanding of the backreaction of anti-D6-branes in a flux background that is mutually BPS with D6-branes. This setup is analogous to the study of the backreaction of anti-D3-branes inserted in the KS throat, but does not require us to smear the anti-branes or do a perturbative analysis around the BPS background. We solve the full equations of motion near the anti-D6-branes and show that only two boundary conditions are consistent with the equations of motion. Upon invoking a topological argument we eliminate the boundary condition with regular H flux since it cannot lead …
We review the method of constructing dipole and string loop solutions from the higher-dimensional (Euclidean) Kerr black hole. We analyse the results in various dimensions, finding solutions earlier given in the literature. Then we construct a new heterotic dipole with non-trivial dilaton and gauge fields. This can, in turn, be describes as a brane/anti-brane pair which interpolates between the KK-dipole and the H-dipole. Finally an argument is presented on the tachyonic instability by analysing the string fluctuations on the dipole background.
The interaction between a parallel brane-antibrane and brane-antibrane is investigated by regarding the brane-antibrane pair as a kink or anti-kink type tachyon condensed state. As the kink-type tachyon condensed state is known as a non-BPS brane we expand the Lagrangian of tachyon effective field theory to the quadratic order in the off-diagonal fluctuation and then use the zeta-function regularization and Schwinger perturbative formula to evaluate the interaction within a kink-kink or a kink-antikink. The results show that while the kink and kink has repulsive force the kink and anti-kink ha…
From the requirement of continuous matching of bulk metric around the point of brane collision we derive a conservation law for collisions of p-branes in (p+2)-dimensional space-time. This conservation law relates energy densities on the branes before and after the collision. Using this conservation law we are able to calculate the amount of matter produced in the collision of orbifold-fixed brane with a bulk brane in the ``ekpyrotic/pyrotechnic type'' models of brane cosmologies.
Placing D3 or anti-D3-branes at the tip of the Klebanov-Strassler background results in uplifting the baryonic branch of the moduli space of the dual field theory. In this paper we derive a mass formula for the scalar particle associated with the motion along the baryonic branch, from both open and closed string points of view. We show that both methods give the same mass at linear order in number of (anti)D3-branes, thus providing a comprehensive check for the recently found linearized supergravity solution describing backreacting anti-D3-branes at the tip.
We revisit the effective low-energy dynamics of the volume modulus in warped flux compactifications with anti-D3-branes in order to analyze the prospects for meta-stable de Sitter vacua and brane inflation along the lines of KKLT/KKLMMT. At the level of the 10d supergravity solution, anti-branes in flux backgrounds with opposite charge are known to source singular terms in the energy densities of the bulk fluxes, which led to a debate on the consistency of such constructions in string theory. A straightforward yet non-trivial check of the singular solution is to verify that its dimensional red…
In this paper the hybrid-NLIE approach of [38] is extended to the ground state of a D-brane anti-D-brane system in AdS/CFT. The hybrid-NLIE equations presented in the paper are finite component alternatives of the previously proposed TBA equations and they admit an appropriate framework for the numerical investigation of the ground state of the problem. Straightforward numerical iterative methods fail to converge, thus new numerical methods are worked out to solve the equations. Our numerical data confirm the previous TBA data. In view of the numerical results the mysterious L = 1 case is also…
We investigate the 3-form singularities that are typical to anti-brane solutions in supergravity and check whether they can be cloaked by a finite temperature horizon. For anti-D3-branes in the Klebanov-Strassler background, this was already shown numerically to be impossible when the branes are partially smeared. In this paper, we present analytic arguments that also localised branes remain with singular 3-form fluxes at both zero and finite temperature. These results may have important, possibly fatal, consequences for constructions of meta-stable de Sitter vacua through uplifting.
We investigate the leading contribution to open string production in the time dependent background of the Brane Anti-Brane. This is a 1-loop diagram and we use Boundary Conformal Field Theory (BCFT) techniques to study it. We show that the amplitude to a single open string naively diverges when one looks at it as an expansion in oscillator levels. Nevertheless, we show that once we sum over all oscillator levels we get a finite result. We also clarify where to perform the inverse Wick rotation in this kind of problems. This calculation could have important consequences for the theory of reheat…
We study the stability of a special form of D brane embedding which is regarded as a bound state of D$_n$ and anti-D$_n$-brane embedded in a 10D supergravity background which is dual to a confining gauge theory. For D5 branes with $U(1)$ flux, their bound state configuration can be regarded as the baryonium vertex. For D branes of $n=6$ and 8 without the $U(1)$ flux, their bound states have been used to introduce flavor quarks in the dual supersymmetric Yang-Mills theory. In any case, it would be important to assure that they are free from tachyon instability. For all these cases, we could sho…
We calculate static Wilson loops for a heavy quark anti-quark pair in different positions in the space generated by a large number of coincident D3-branes. Simple results are obtained from limiting cases of the geodesic shape. In particular, quark anti-quark static potentials for flat and AdS spaces are reproduced.
We investigate the thermodynamic properties of D-brane-anti-D-brane pairs and non-BPS D-branes on the basis of boundary string field theory. We calculate the finite temperature effective potential of N D-brane-anti-D-brane pairs in a non-compact background and in a toroidal background. In the non-compact background case, a phase transition occurs slightly below the Hagedorn temperature, and the D9-anti-D9 pairs become stable. Moreover, the total energy at the critical temperature is a decreasing function of N as long as the 't Hooft coupling is very small. This leads to the conclusion that a l…
We elaborate on the decay of branes inside throat geometries that are supported by flux carrying charges opposite to the brane. Our main point is that such backgrounds necessarily have a local, possibly diverging, pile up of brane-charges dissolved in flux around the anti-brane due to the (fatal) attraction of the flux towards the brane. We explain that this causes enhanced brane-flux annihilation and is in tension with the idea that anti-branes can be used to construct meta-stable vacua. We argue that stable configurations -- if they at all exist -- are not obtainable within SUGR. The problem…
We study the anti-de Sitter D-brane dynamics in Hamiltonian formulation. By exploiting the existence of certain conserved charges, we solve the equation of motion for a D1-brane in the AdS3 background and find the space-time dependent solutions. We further study the dynamics by mapping the problem to that of the open string tachyon, and examine the time dependent solutions in some detail.
We construct analytically a perturbative supergravity solution that captures the backreaction of a metastable state of anti-branes in the background of a particular modification of the Klebanov-Strassler throat in a long-wavelength approximation. Our solution, which has no unphysical singularities, describes how non-supersymmetric spherical NS5-branes with dissolved anti-D3 brane charge backreact in a fluxed throat geometry. It supports previous claims that there is a well-behaved supergravity description of the metastable state of wrapped NS5-branes proposed years ago by Kachru, Pearson, and …
Using world-sheet parity we show that mixed D and N components of D-strings are dual to the anti-symmetric $B_{μν}$ field. The contribution of the latter is responsible for the reduction and even removal of all the interactions between two dissimilar D-branes.
We review some facts about AdS2xS2 branes in AdS3xS3 with a Neveu-Schwarz background, and consider the case of Ramond-Ramond backgrounds. We compute the spectrum of quadratic fluctuations in the low-energy approximation and discuss the open-string geometry.
We use a D5-brane with electric flux in AdS_5 x S^5 background to calculate the circular Wilson loop of anti-symmetric representation in N=4 super Yang-Mills theory in 4 dimensions. The result agrees with the Gaussian matrix model calculation.
We study the dynamics of localized and fully backreacting anti-D3 branes at the tip of the Klebanov-Strassler geometry. We use a non-supersymmetric version of the Polchinski-Strassler analysis to compute the potential for anti-D3 branes to polarize into all kinds of five-brane shells in all possible directions. We find that generically there is a direction along which the brane-brane interaction is repulsive, which implies that anti-D3 branes are tachyonic. Hence, even though anti-D3 branes can polarize into five-branes, the solution will most likely be unstable. This indicates that anti-D3 br…
We construct the SO(32) spinor state in weakly coupled type I string theory as a kink solution of the tachyon field on the D-string - anti-D-string pair and calculate its mass. We also give a description of this system in terms of an exact boundary conformal field theory and show that in this description this state can be regarded as a non-supersymmetric D0-brane in type I string theory. This construction can be generalised to represent the D0-brane in type IIA string theory as a vortex solution of the tachyon field on the membrane anti-membrane pair, and the D-string of type I string theory a…
Compactifications of type IIB string theory on AdS5 x X5, where X5 is an Einstein space, can have one-fourth or half maximal supersymmetry for certain choices of X5. Some of these theories admit exotic domain walls arising from 5-branes wrapping 2-cycles in X5. We explore the relationship among these domain walls, fractional branes and branes stretched on intervals. World-volume fluxes in the wrapped branes play an important role in the analysis. We draw some parallels between the AdS background with exotic domain walls and N=1 supersymmetric MQCD, and identify other extended objects on the Ad…
We present some preliminary investigations about the AdS2*S2 D3-branes in AdS3*S3. We analyse the quadratic fluctuations of Dirac-Born-Infeld action around a given semi-classical D-brane configuration and compare them with results obtained by using conformal field theory techniques. We finally study classical motions of open strings attached to those D-branes and analyse the role of the spectral flow in this context.
We study the effect of brane polarization on the supersymmetry transformations of probe anti-D3-branes at the tip of a Klebanov-Strassler throat geometry. As is well known, the probe branes can polarize into NS5-branes and decay to a supersymmetric state by brane-flux annihilation. The effective potential has a metastable minimum as long as the number of anti-D3-branes is small compared to the number of flux quanta. We study the reduced four-dimensional effective NS5-brane theory and show that in the metastable minimum supersymmetry is non-linearly realized to leading order, as expected for sp…
A simple, KKLT-like construction of de Sitter vacua in type IIA string theory is presented in an STU model with guidance from string theory U-duality and with an uplifting anti-D6-brane. In four dimensions the model is reduced to $\mathcal{N}=1$ supergravity with three chiral multiplets, namely $S$, $T$ and $U$, as well as one nilpotent multiplet representing the anti-D6-brane.
Using the tachyon DBI action proposal for the effective theory of non-coincident D$_p$-brane-anti-D$_p$-brane system, we study the decay of this system in the tachyon channel. We assume that the branes separation is held fixed, i.e. no throat formation, and then find the bounce solution which describe the decay of the system from false to the true vacuum of the tachyon potential. We shall show that due to the non-standard form of the kinetic term in the effective action, the thin wall approximation for calculating the bubble nucleation rate gives a result which is independent of the branes sep…
It has been recently argued that inserting a probe anti-D3-brane in a flux background breaks supersymmetry spontaneously instead of explicitly, as previously thought. In this paper we argue that such spontaneous breaking of supersymmetry persists even when the probe anti-D3-brane is kept in a curved background with an internal space that doesn't have to be a Calabi-Yau manifold. To show this we take a specific curved background generated by fractional three-branes and fluxes on a non-Kahler resolved conifold where supersymmetry breaking appears directly from certain world-volume fermions becom…
We revisit necessary conditions for gluing local (anti-)D3 throats into flux throats with opposite charge. These consistency conditions typically reveal singularities in the three-form fluxes whose meaning is being debated. In this note we prove, under well-motivated assumptions, that unphysical singularities can potentially be avoided when the anti-branes polarise into spherical NS5 branes with a specific radius. If a consistent solution can then indeed be found, our analysis seems to suggests a rather large correction to the radius of the polarization sphere compared to the probe result. We …
We study D-branes of the ${SL(2,\bR)}$ WZW model, and of its discrete orbifolds. Gluing the currents by group automorphisms leads to three types of D-branes: two-dimensional hyperbolic planes ($H_2$), de Sitter branes (dS$_2$), or anti-de-Sitter branes (AdS$_2$). We explain that the dS$_2$ branes are unphysical, because the electric field on their worldvolume is supercritical. By combining ${SL(2,\bR)}$ and SU(2), we exhibit a class of supersymmetric AdS$_2\times S^2$ three-brane worldvolumes, and consider their possible embeddings in the near-horizon region of stringy black holes. We point ou…
We construct the effective action of a $D_p$-brane-anti-$D_p$-brane system by making use of the non-abelian extension of tachyonic DBI action. We succeed the construction by restricting the Chan-Paton factors of two non-BPS $D_p$-branes in the action to the Chan-Paton factors of a $D_p\bar{D}_p$ system. For the special case that both branes are coincident, the action reduces to the one proposed by A. Sen. \\The effective $D_p\bar{D}_p$ potential indicates that when branes separation is larger than the string length scale, there are two minima in the tachyon direction. As branes move toward eac…
We find the superpotential governing the supersymmetric warped M-theory solution with a transverse Stenzel space found by Cvetic, Gibbons, Lu and Pope in hep-th/0012011, and use this superpotential to extract and solve the twelve coupled equations underlying the first-order backreacted solution of a stack of anti-M2 branes in this space. These anti-M2 branes were analyzed recently in a probe approximation by Klebanov and Pufu, who conjectured that they should be dual to a metastable vacuum of a supersymmetric 2+1 dimensional theory. We find that the would-be supergravity dual to such a metasta…
We present the potential energy due to flux and gaugino condensation in heterotic M-theory compactifications with anti-branes in the vacuum. For reasons which we explain in detail, the contributions to the potential due to flux are not modified from those in supersymmetric contexts. The discussion of gaugino condensation is, however, changed by the presence of anti-branes. We show how a careful microscopic analysis of the system allows us to use standard results in supersymmetric gauge theory in describing such effects - despite the explicit supersymmetry breaking which is present. Not surpris…
We argue that a modification of the super-AdS algebras which accounts for the presence of D-branes requires not only the inclusion of bosonic brane charges, but also the inclusion of new fermionic ones. We show that such fermionic brane charges are indeed present in the matrix model and the supermembrane in the pp-wave limit of the corresponding backgrounds. We briefly comment on an AdS version of Sezgin's M-algebra inspired by this observation.
We consider explicit type II string constructions of backgrounds containing warped and squashed anti de Sitter spaces. These are obtained via T duality from brane intersections including dyonic black strings, plane waves and monopoles. We also study the supersymmetry of these solutions and discuss special values of the deformation parameters.
The force between like sign BPS saturated objects generally vanishes. This is a reflection of the fact that BPS states are really massless uncharged particles with nonvanishing momenta in compactified directions. Two like sign BPS objects with zero relative velocity can be viewed as a boosted state of two neutral massless particles in a state of vanishing relative motion. By contrast two unlike sign BPS particles may be thought of as colliding objects moving in opposite directions in compact space. This leads to complicated interactions which are totally intractable at present. We illustrate t…
