arXiv subjects

Igor A. Bandos

Publications and source records attributed to Igor A. Bandos.

At least 37 records · Page 2Linked to original sources

arXiv2010

On multiple M2-brane model(s) and its N=8 superspace formulation(s)

We give a brief review of Bagger-Lambert-Gustavsson (BLG) model, with emphasis on its version invariant under the volume preserving diffeomorphisms (SDiff3) symmetry. We describe the on-shell superfield formulation of this SDiff3 BLG model in standard N=8, d=3 superspace, as well as its superfield action in the pure spinor N=8 superspace. We also briefly address the Aharony-Bergman-Jafferis-Maldacena (ABJM/ABJ) model invariant under $SU(M)_{k}\times SU(N')_{-k}$ gauge symmetry, and discuss the possible form of their N=6 and, for the case of Chern-Simons level k=1,2, N=8 superfield equations.

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arXiv2010

Superembedding approach to M0-brane and multiple M0-brane system

We study the possibility to describe multiple M0-brane system in the frame of superembedding approach. The simplest framework is provided by the maximally supersymmetric non-Abelian SU(N) Yang-Mills supermultiplet on the d=1 N=16 superspace the embedding of which to the target D=11 supergravity superspace is determined by the so-called superembedding equation, characteristic of the worldline superspace of a single M0-brane. We use it to obtain a covariant generalization of the Matrix model equations describing the multiple M0-system in flat target superspace.

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arXiv2010

Spacetime Brout-Englert-Higgs effect in General Relativity interacting with p-brane matter

We review the manifestation of the Brout-Englert-Higgs effect in general relativity interacting with point-like and extended objects (p-branes including string for p=1 and membrane for p=2), which manifests itself in the appearance of the brane source in the Einstein equation while the graviton remains massless (hep-th/0112207, hep-th/0507197 and refs therein), and discuss briefly its relation and differences with the model for massive spin 2 field proposed recently by G. t'Hooft in [arXiv:0708.3184 [hep-th]].

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arXiv2009

On superembedding approach to multiple D-brane system. D0 story

We develop superembedding approach to multiple D-particle (D0-brane) system. In flat target D=10 type IIA superspace this produces the supersymmetric and Lorentz covariant version of the Matrix model equations. The equations following from our superembedding approach to multiple D0 in curved type IIA superspace shows the Myers 'dielectric brane effect', i.e. interaction with higher form gauge fields which do not interact with a single D0-brane.

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arXiv2009

Superembedding approach to superstring in AdS(5)xS*5 superspace

We review the spinor moving frame formulations and generalized action principle for super-p-branes, describe in detail the superembedding approach to superstring in general type IIB supergravity background and present the complete superembedding description of type IIB superstring in the AdS(5)xS*5 superspace.

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arXiv2009

On superembedding approach to type IIB 7-branes

In search for a dynamical description of Q7-branes, which were known as solutions of supergravity equations and then conjectured to be dynamical objects of type IIB string theory, we study the superembedding description of 7-branes in curved type IIB supergravity superspace. With quite minimal and natural assumptions we have found that there is no place for Q7-branes as dynamical branes in superembedding approach. Our study might give implications for the old-standing problem of the covariant and supersymmetric description of multiple Dp-brane systems.

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arXiv2009

SDiff Gauge Theory and the M2 Condensate

We develop a general formalism for the construction, in $D$-dimensional Minkowski space, of gauge theories for which the gauge group is the infinite-dimensional group SDiff$_n$ of volume-preserving diffeomorphisms of some closed $n$-dimensional manifold. We then focus on the D=3 SDiff$_3$ superconformal gauge theory describing a condensate of M2-branes; in particular, we derive its ${\cal N}=8$ superfield equations from a pure-spinor superspace action, and we describe its relationship to the D=3 SDiff$_2$ super-Yang-Mills theory describing a condensate of D2-branes.

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arXiv2008

NB BLG model in N=8 superfields

We develop the N=8 superfield description of the Bagger-Lambert-Gustavsson (BLG) model in its Nambu bracket (NB) realization. The basic ingredient is the octet of scalar d=3 N=8 superfields depending also on the coordinates of a compact three dimensional space M. It is restricted by the 'superembedding-like' equation, which can be treated as covariantization of the linearized superembedding equation for supermembrane (M2-brane) with respect volume preserving diffeomorphisms SDiff3 of M. The curvatures of SDiff3 connection are expressed through the scalar superfields by the N=8 superfield generalization of the Chern-Simons equation (super-CS equation). We show how the dynamical BLG equations appear when studying consistency of these basic equations.

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arXiv2008

Light-cone M5 and multiple M2-branes

We present the light-cone gauge fixed Lagrangian for the M5-brane; it has a residual `exotic' gauge invariance with the group of 5-volume preserving diffeomorphisms, SDiff(5), as gauge group. For an M5-brane of topology R2 x M3, for closed 3-manifold M3, we find an infinite tension limit that yields an SO(8)-invariant (1+2)-dimensional field theory with `exotic' SDiff(3) gauge invariance. We show that this field theory is the Carrollian limit of the Nambu bracket realization of the `BLG' model for multiple M2-branes.

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arXiv2008

BPS preons and the AdS-M-algebra

We present here the AdS generalization of BPS preons, which were introduced as the hypothetical constituents of M-theory preserving all but one supersymmetries. Our construction, suggested by the relation of `lower dimensional preons' with higher spin theories, can be considered as a deformation of the M-algebraic description of the single supersymmetry broken by a preon, and provides another reason to identify the AdS generalization of the M-algebra, which we call the AdS-M-algebra, with osp(1|32).

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arXiv2008

D=11 massless superparticle covariant quantization, pure spinor BRST charge and hidden symmetries

We consider the covariant quantization of the D=11 massless superparticle (M0-brane) in the spinor moving frame or twistor-like Lorentz harmonics formulation. The action involves the set of 16 constrained 32 component Majorana spinors, the spinor Lorentz harmonics parametrizing (as homogeneous coordinates, modulo gauge symmetries) the celestial sphere S9. There presence allows us to separate covariantly the first and the second class constraints of the model. After taking into account the second class constraints by means of Dirac brackets and after further reducing the first class constraints algebra, the system is described in terms of a simple BRST charge associated to the d=1, n=16 supersymmetry algebra. The study of the cohomology of this BRST operator requires a regularization by complexifying the bosonic ghosts for the kappa-symmetry and further reduction of the regularized cohomology problem to the one for a simpler complex BRST charge which is essentially the pure spinor BRST operator by Berkovits, but with a composite pure spinor. This exhibits a possible origin of the complexity (non-hermiticity) characteristic of the Berkovits pure spinor approach. The simple structure of the nontrivial cohomology of the M0-brane BRST charge finds explanation in the properties that the superparticle action exhibits in the so-called `covariantized light-cone' basis. The the covariant quantization in this basis hints possible hidden symmetries of D=11 supergravity. Besides SO(16), we discuss also some indirect arguments in favor of the possible E8 symmetry.

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arXiv2008

On covariant quantization of M0-brane. Spinor moving frame, pure spinor formalism and hidden symmetries of D=11 supergravity

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.

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arXiv2007

Spinor moving frame, M0-brane covariant BRST quantization and intrinsic complexity of the pure spinor approach

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 cohomology of a simple BRST charge associated to the d=1, n=16 supersymmetry algebra. The calculation of the cohomology of this BRST operator requires a regularization which implies the complexification of the bosonic ghost associated to the kappa-symmetry and further leads to a complex (non-Hermitian) BRST charge which is essentially the `pure spinor' BRST operator by Berkovits, but with a composite pure spinor.

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arXiv2007

Twistor string as tensionless superstring

We give a brief review of the twistor string approach to supersymmetric Yang-Mills theories with an emphasis on the different formulations of (super)string models in supertwistor space and their superspace form. We discuss the classical equivalence among the Siegel closed twistor string and the Lorentz harmonics formulation of the (N=4) tensionless superstring, and notice the possible relation of the twistor string to the D=10 Green-Schwarz superstring action, as well as to models in the enlarged, tensorial superspaces that are relevant in higher spin theories.

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arXiv2007

On D=11 supertwistors, superparticle quantization and a hidden SO(16) symmetry of supergravity

We consider a covariant quantization of the D=11 massless superparticle in the supertwistor framework. D=11 supertwistors are highly constrained, but the interpretation of their bosonic components as Lorentz harmonic variables and their momenta permits to develop a classical and quantum mechanics without much difficulties. A simple, heuristic `twistor' quantization of the superparticle leads to the linearized D=11 supergravity multiplet. In the process, we observe hints of a hidden SO(16) symmetry of D=11 supergravity.

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arXiv2006

BPS preons and higher spin theory in D=4, 6, 10

We briefly review here the notion of BPS preons, the hypothetical constituents of M-theory, emphasizing its generalization to arbitrary dimensions D and its relation to higher spin theories in D=4,6 and 10.

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arXiv2006

On the absence of BPS preonic solutions in IIA and IIB supergravities

We consider the present absence of 31 out of 32 supersymmetric solutions in supergravity i.e., of solutions describing BPS preons. A recent result indicates that (bosonic) BPS preonic solutions do not exist in type IIB supergravity. We reconsider this analysis by using the G-frame method, extend it to the IIA supergravity case, and show that there are no (bosonic) preonic solutions for type IIA either. For the classical D=11 supergravity no conclusion can be drawn yet, although the negative IIA results permit establishing the conditions that preonic solutions would have to satisfy. For supergravities with `stringy' corrections, the existence of BPS preonic solutions remains fully open.

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arXiv2006

Superspace formulations of the (super)twistor string

The superspace formulation of the worldvolume action of twistor string models is considered. It is shown that for the Berkovits-Siegel closed twistor string such a formulation is provided by a N=4 twistor-like action of the tensionless superstring. A similar inverse twistor transform of the open twistor string model (Berkovits model) results in a dynamical system containing two copies of the D=4, N=4 superspace coordinate functions, one left-moving and one right-moving, that are glued by the boundary conditions. We also discuss possible candidates for a tensionful superstring action leading to the twistor string in the tensionless limit as well as multidimensional counterparts of twistor strings in the framework of both `standard' superspace and superspace enlarged by tensorial coordinates (tensorial superspaces), which constitute a natural framework for massless higher spin theories.

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