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M. A. Vasiliev

Publications and source records attributed to M. A. Vasiliev.

At least 91 records · Page 5Linked to original sources

Higher Spin Gauge Theories in Various Dimensions

Properties of nonlinear higher spin gauge theories of totally symmetric massless higher spin fields in anti-de Sitter space of any dimension are discussed with the emphasize on the general aspects of the approach.

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Cubic Interactions of Bosonic Higher Spin Gauge Fields in $AdS_5$

The dynamics of totally symmetric free massless higher spin fields in $AdS_d$ is reformulated in terms of the compensator formalism for AdS gravity. The $AdS_5$ higher spin algebra is identified with the star product algebra with the $su(2,2)$ vector (i.e., $o(4,2)$ spinor) generating elements. Cubic interactions of the totally symmetric bosonic higher spin gauge fields in $AdS_5$, including the interaction with gravity, are formulated at the action level.

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On the Frame-Like Formulation of Mixed-Symmetry Massless Fields in (A)dS(d)

The frame-like covariant Lagrangian formulation of bosonic and fermionic mixed-symmetry type higher spin massless fields propagating on the AdS(d) background is proposed. Higher spin fields are described in terms of gauge p-forms which carry tangent indices representing certain traceless tensor or gamma transversal spinor-tensor representations of the AdS(d) algebra o(d-1,2) (or o(d,1) for bosonic fields in dS(d)). Manifestly gauge invariant Abelian higher spin field strengths are introduced for the general case. We describe the general framework and demonstrate how it works for the mixed-symmetry type fields associated with the three-cell "hook" and arbitrary two-row rectangular tableaux. The manifestly gauge invariant actions for these fields are presented in a simple form. The flat limit is also analyzed.

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J/Psi Polarization in 800-GeV p-Cu Interactions

We present measurements of the polarization of the $ J/ψ$ produced in 800-GeV proton interactions with a copper target. Polarization of the $ J/ψ$ is sensitive to the $ c \bar{c} $ production and hadronization processes. A longitudinal polarization is observed at large $ x_{F} $, while at small $ x_{F} $ the state is produced essentially unpolarized or slightly transversely polarized. No significant variation of the polarization is observed versus $ p_{T} $.

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Star-Product and Massless Free Field Dynamics in $AdS_4$

Generic solution of free equations for massless fields of an arbitrary spin in $AdS_4$ is built in terms of the star-product algebra with spinor generating elements. A class of "plane wave" solutions is described explicitly.

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Absolute Drell-Yan Dimuon Cross Sections in 800 GeV/c pp and pd Collisions

The Fermilab E866/NuSea Collaboration has measured the Drell-Yan dimuon cross sections in 800 GeV/$c$ $pp$ and $pd$ collisions. This represents the first measurement of the Drell-Yan cross section in $pp$ collisions over a broad kinematic region and the most extensive study to date of the Drell-Yan cross section in $pd$ collisions. The results indicate that recent global parton distribution fits provide a good description of the light antiquark sea in the nucleon over the Bjorken-$x$ range $0.03 \lesssim x < 0.15$, but overestimate the valence quark distributions as $x \to 1$.

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Higher-Spin Theories and $Sp(2M)$ Invariant Space--Time

Some methods of the ``unfolded dynamics'' machinery particularly useful for the analysis of higher spin gauge theories are summarized. A formulation of 4d conformal higher spin theories in Sp(8) invariant space-time with matrix coordinates and its extension to Sp(2M) invariant space-times are discussed. A new result on the global characterizaton of causality of physical events in the Sp(2M) invariant space-time is announced.

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Progress in Higher Spin Gauge Theories

General properties of the theory of higher spin gauge fields in $AdS_4$ are discussed. Some new results on the 4d conformal higher spin gauge theory are announced. Talk given at the International Conference "Quantization, Gauge Theory and Strings" in memory of E.S.Fradkin, Moscow, June 5-10, 2000.

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Conformal Higher Spin Symmetries of 4d Massless Supermultiplets and $osp(L,2M)$ Invariant Equations in Generalized (Super)Space

Realization of the conformal higher spin symmetry on the 4d massless field supermultiplets is given. The self-conjugated supermultiplets, including the linearized ${\cal N}=4$ SYM theory, are considered in some detail. Duality between non-unitary field-theoretical representations and the unitary doubleton--type representations of the 4d conformal algebra $su(2,2)$ is formulated in terms of a Bogolyubov transform. The set of 4d massless fields of all spins is shown to form a representation of $sp(8)$. The obtained results are extended to the generalized superspace invariant under $osp(L, 2M)$ supersymmetries. World line particle interpretation of the free higher spin theories in the $osp(2\N, 2M)$ invariant (super)space is given. Compatible with unitarity free equations of motion in the $osp(L,2M)$ invariant (super)space are formulated. A conjecture on the chain of $AdS_{d+1}/CFT_d \to AdS_{d}/CFT_{d-1} \to ...$ dualities in the higher spin gauge theories is proposed.

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Higher Spin Conserved Currents in $Sp(2M)$ Symmetric Spacetime

Infinite set of higher spin conserved charges is found for the $sp(2M)$ symmetric dynamical systems in $\f{1}{2} M (M+1)$-dimensional generalized spacetime $\M_M$. Since the dynamics in $\M_M$ is equivalent to the conformal dynamics of infinite towers of fields in $d$-dimensional Minkowski spacetime with $d=3,4,6,10,...$ for $M=2,4,8,16, ...$, respectively, the constructed currents in $\M_M$ generate infinite towers of (mostly new) higher spin conformal currents in Minkowski spacetime. The charges have a form of integrals of $M$-forms which are bilinear in the field variables and are closed as a consequence of the field equations. Conservation implies independence of a value of charge of a local variation of a $M$-dimensional integration surface $Σ\subset \M_M$ analogous to Cauchy surface in the usual spacetime. The scalar conserved charge provides an invariant bilinear form on the space of solutions of the field equations that gives rise to a positive definite norm on the space of quantum states.

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Relativity, Causality, Locality, Quantization and Duality in the $Sp(2M)$ Invariant Generalized Space-Time

We analyze properties of the Sp(2M) conformally invariant field equations in the recently proposed generalized $\half M(M+1)$-dimensional space-time $\M_M$ with matrix coordinates. It is shown that classical solutions of these field equations define a causal structure in $\M_M$ and admit a well-defined decomposition into positive and negative frequency solutions that allows consistent quantization in a positive definite Hilbert space. The effect of constraints on the localizability of fields in the generalized space-time is analyzed. Usual d-dimensional Minkowski space-time is identified with the subspace of the matrix space $\M_M$ that allows true localization of the dynamical fields. Minkowski coordinates are argued to be associated with some Clifford algebra in the matrix space $\M_M$. The dynamics of a conformal scalar and spinor in $\M_2$ and $\M_4$ is shown to be equivalent, respectively, to the usual conformal field dynamics of a scalar and spinor in the 3d Minkowski space-time and the dynamics of massless fields of all spins in the 4d Minkowski space-time. An extension of the electro-magnetic duality transformations to all spins is identified with a particular generalized Lorentz transformation in $\M_4$. The M=8 case is shown to correspond to a 6d chiral higher spin theory. The cases of M=16 (d=10) and M=32 (d=11) are discussed briefly.

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Higher Spin Conformal Symmetry for Matter Fields in 2+1 Dimensions

A simple realization of the conformal higher spin symmetry on the free $3d$ massless matter fields is given in terms of an auxiliary Fock module both in the flat and $AdS_3$ case. The duality between non-unitary field-theoretical representations of the conformal algebra and the unitary (singleton--type) representations of the $3d$ conformal algebra $sp(4,\R)$ is formulated explicitly in terms of a certain Bogolyubov transform.

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Observation of Polarization in Bottomonium Production at sqrt(s)=38.8 GeV

We present a measurement of the polarization observed for bottomonium states produced in p-Cu collisions at sqrt(s)=38.8 GeV. The angular distribution of the decay dimuons of the Upsilon(1S) state show no polarization at small xF and pT but significant positive transverse production polarization for either pT > 1.8 GeV/c or for xF > 0.35. The Upsilon(2S+3S) unresolved states show a large transverse production polarization at all values of xF and pT measured. These observations are compared with an NRQCD calculation that predicts a transverse polarization in bottomonium production arising from quark-antiquark fusion and gluon-gluon fusion diagrams.

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Conformal Higher Spin Currents in Any Dimension and AdS/CFT Correspondence

The full list of conserved conformal higher spin currents built from massless scalar and spinor fields is presented. It is shown that, analogously to the relationship between usual conformal and AdS symmetries, the set of the conformal higher spin symmetry parameters associated with the conformal conserved currents in d dimensions is in the one-to-one correspondence with the result of the dimensional reduction of the usual (i.e., non-conformal) higher spin symmetry parameters in d+1 dimensions.

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How massless are massless fields in $AdS_d$

Massless fields of generic Young symmetry type in $AdS_d$ space are analyzed. It is demonstrated that in contrast to massless fields in Minkowski space whose physical degrees of freedom transform in irreps of $o(d-2)$ algebra, $AdS$ massless mixed symmetry fields reduce to a number of irreps of $o(d-2)$ algebra. From the field theory perspective this means that not every massless field in flat space admits a deformation to $AdS_d$ with the same number of degrees of freedom, because it is impossible to keep all of the flat space gauge symmetries unbroken in the AdS space. An equivalent statement is that, generic irreducible AdS massless fields reduce to certain reducible sets of massless fields in the flat limit. A conjecture on the general pattern of the flat space limit of a general $AdS_d$ massless field is made. The example of the three-cell ``hook'' Young diagram is discussed in detail. In particular, it is shown that only a combination of the three-cell flat-space field with a graviton-like field admits a smooth deformation to $AdS_d$.

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