Dmitriy V. Uvarov

An Inverse Penrose Limit and Supersymmetry Enhancement in the Presence of Tensor Central Charges

A connection between weak and strong tension limits and their perturbative corrections is discussed. New twistor-like models based on D = 4, N = 1 tensionless superstring and superbrane with tensor central charges are studied. The presence of three, two or less preserved fractions of κ-symmetry in the actions free of the Wess-Zumino terms is shown. A correlation of extra κ-symmetry with the R-symmetry is established. The equations of the superstring and superbrane models preserving 3/4 supersymmetry are exactly solved. The general solution for the Goldstone fermion is pure static, but for the Goldstone bosons it also includes a term describing string/brane motions along the fixed directions given by the initial data. These solutions correspond to the partial spontaneous breaking of the D = 4, N = 1 global supersymmetry and can be associated with a static closed magnetic Nielsen-Olesen vortex or a p-dimensional vortex.

LIGHT-CONE GAUGE HAMILTONIAN FOR AdS4 × ℂℙ3 SUPERSTRING

We develop the phase-space formulation for the Type IIA superstring on the AdS4 × ℂℙ3 background in the κ-symmetry light-cone gauge for which the light-like directions are taken from the D = 3 Minkowski boundary of AdS4. After fixing bosonic light-cone gauge, the superstring Hamiltonian is expressed as a function of the transverse physical variables and in the quadratic approximation corresponds to the light-cone gauge-fixed IIA superstring in flat space.

Exactly solvable p-brane model with extra supersymmetry

Abstract Effect of the supersymmetry enhancement due to the presence of tensor central charge coordinates in the models of tensionless superstring and superbrane is studied. Exactly solvable super p -brane model preserving 3/4 of the D =4, N =1 supersymmetry is presented. The fine tuning of extra κ -symmetry with the R -symmetry is observed. We show that the general solution for the Goldstone fermion is pure static.

Extra gauge symmetry for extra supersymmetry

Abstract It is shown that the extra supersymmetry of tensionless superstring and super p -brane is accompanied by the presence of new bosonic gauge symmetries. It permits to use composed coordinates encoding all physical degrees of freedom of the model and invariant under these gauge symmetries and the enhanced κ -symmetry. It is proved that the composed gauge invariant coordinates coincide with the components of symplectic supertwistor realizing a linear representation of the hidden OSp (1,2 M ) symmetry of the super p -brane Lagrangian. A connection of the presented gauge symmetries with massless higher spin gauge theories and a symmetric phase of M/string-theory is discussed.

Ambitwistors, oscillators and massless fields on AdS5

Abstract Positive energy unitary irreducible representations of S U ( 2 , 2 ) can be constructed with the aid of bosonic oscillators in (anti)fundamental representation of S U ( 2 ) L × S U ( 2 ) R that are closely related to Penrose twistors. Starting with the correspondence between the doubleton representations, homogeneous functions on projective twistor space and on-shell generalized Weyl curvature S L ( 2 , C ) spinors and their low-spin counterparts, we study in the similar way the correspondence between the massless representations, homogeneous functions on ambitwistor space and, via the Penrose transform, with the gauge fields on Minkowski boundary of AdS 5 . The possibilities of reconstructing massless fields on AdS 5 and some applications are also discussed.

Hamiltonian structure and noncommutativity in p-brane models with exotic supersymmetry

The hamiltonian of the simplest twistor super p-brane model preserving 3/4 of the D = 4 N = 1 supersymmetry in the centrally extended symplectic superspace is derived and its symmetries are described. The constraints of the model are covariantly separated into the first- and the second-class sets and the Dirac brackets (D.B.) are constructed. We show the D.B. noncommutativity of the super p-brane coordinates in extended twistor superspace and find the D.B. realization of the OSp(1|8) superalgebra. Established is the coincidence of the D.B. and Poisson bracket realizations of the OSp(1|8) superalgebra on the constraint surface and the absence there of anomaly terms in the commutation relations for the quantized generators of the superalgebra.

N = 2 Supersymmetric Yang–Mills Theory and the Superparticle: Twistor Transform and κ-Symmetry

Lagrangian and Hamiltonian dynamics of de Azcarraga-Lukierski N=2 massive superparticle is considered in the framework of twistor-like Lorentz-harmonic approach. The emphasis is on the study of the interaction with external Abelian gauge superfield. The requirement of preservation of all gauge symmetries of the free model including kappa-symmetry yields correct expressions for the superfield strength constraints and determines the form of nonminimal interaction. We also show that for de Azcarraga-Lukierski N=2 massive superparticle the pullback of field strength 2-superform to the superworld line is not integrable in contrast to the massless superparticle.

New Superembeddings for Type II Superstrings

Possible ways of generalization of the superembedding approach for the supersurfaces with the number of Grassmann directions being less than the half of that for the target superspace are considered on example of Type II superstrings. Focus is on n=(1,1) superworldsheet embedded into D=10 Type II superspace that is of the interest for establishing a relation with the NSR string.

Covariant κ—symmetry gauge fixing and the classical relation between physical variables of the NSR string and the type II GS superstring

Abstract The main goal of this paper is the manifestly covariant derivation of the classical relation between the gauge-fixed Grassmann variables of the NSR string and the Type II GS superstring. To this end we analyze the superembedding equation for the Type II superstring to derive the relation between the original variables of the NSR string and the Type II GS superstring and, further, by means of Lorentz harmonic variables we fix κ—symmetry of the GS superstring in the manifestly Lorentz covariant way.

Quantum BRST Charge and OSp(1|8) Superalgebra of Twistor‐Like p‐branes with Exotic Supersymmetry and Weyl Symmetry

Classical and quantum realizations of the BRST charge and unified superalgebra of the global superconformal OSp(1|8) and generalized Virasoro and Weyl symmetries, generated by p−branes preserving 34 fraction of D = 4 N = 1 supersymmetry, are presented and their possible anomalies are described.