Searcharxiv⌕ Search

arXiv subjects

M. A. Vasiliev

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

At least 73 records · Page 4Linked to original sources
arXiv2009

Unfolded Dynamics and Parameter Flow of Generic AdS(4) Black Hole

We present unfolded description of AdS(4) black hole with generic parameters of mass, NUT, magnetic and electric charges as well as two kinematical parameters one of which is angular momentum. A flow with respect to black hole parameters, that relates the obtained black hole unfolded system to the covariant constancy condition for an AdS(4) global symmetry parameter, is found. The proposed formulation gives rise to a coordinate-independent description of the black hole metric in AdS(4). The black hole charges are identified with flow evolution parameters while its kinematical constants are the first integrals of the black hole unfolded system expressed via invariants of the AdS(4) global symmetry parameter. It is shown how the proposed method reproduces various known forms of black hole metrics including the Carter and Kerr-Newman solutions. Free flow gauge parameters allow us to choose different metric representations such as Kerr-Schild, double Kerr-Schild or generalized Carter-Plebanski in the coordinate-independent way.

hep-th↗
arXiv2008

On Dimensional Degression in AdS(d)

We analyze the pattern of fields in d+1 dimensional anti-de Sitter space in terms of those in d dimensional anti-de Sitter space. The procedure, which is neither dimensional reduction nor dimensional compactification, is called dimensional degression. The analysis is performed group-theoretically for all totally symmetric bosonic and fermionic representations of the anti-de Sitter algebra. The field-theoretical analysis is done for a massive scalar field in AdS(d+d$^\prime$) and massless spin one-half, spin one, and spin two fields in AdS(d+1). The mass spectra of the resulting towers of fields in AdS(d) are found. For the scalar field case, the obtained results extend to the shadow sector those obtained by Metsaev in [1] by a different method.

hep-th↗
arXiv2008

Unfolded Description of $AdS_4$ Kerr Black Hole

It is shown that $AdS_4$ Kerr black hole is a solution of simple unfolded differential equations that form a deformation of the zero-curvature description of empty $AdS_4$ space-time. Our construction uses the Killing symmetries of the Kerr solution. All known and some new algebraic properties of the Kerr-Schild solution result from the obtained black hole unfolded system in the coordinate-independent way. Kerr Schild type solutions of free equations in $AdS_4$ for massless fields of any spin, associated to the proposed black hole unfolded system, are found.

gr-qc↗
arXiv2007

On Conformal, SL(4,R) and Sp(8,R) Symmetries of 4d Massless Fields

The $sp(8, R)$ invariant formulation of free field equations of massless fields of all spins in $AdS_4$ available previously in terms of gauge invariant field strengths is extended to gauge potentials. As a by-product, free field equations for a massless gauge field are shown to possess both $su(2,2)\sim o(4,2)$ and $sl(4,R)\sim o(3,3)$ symmetry. The proposed formulation is well-defined in the $AdS_4$ background but experiences certain degeneracy in the flat limit that does not allow conformal invariant field equations for spin $s>1$ gauge fields in Minkowski space. The basis model involves the doubled set of fields of all spins. It is manifestly invariant under U(1) electric-magnetic duality extended to higher spins. Reduction to a single massless field contains the equations that relate its electric and magnetic potentials which are mixed by the conformal transformations for s>1. We use the unfolded formulation approach recalled in the paper with some emphasis on the role of Chevalley-Eilenberg cohomology of a Lie algebra $g$ in $g$-invariant field equations. This method makes it easy to guess a form of the 4d $sp(8, R)$ invariant massless field equations and then to extend them to the ten dimensional $sp(8,R)$ invariant space-time. Dynamical content of the field equations is analyzed in terms of $σ_-$ cohomology.

hep-th↗
arXiv2007

BTZ Black Hole as Solution of 3d Higher Spin Gauge Theory

BTZ black hole is interpreted as exact solution of 3d higher spin gauge theory. Solutions for free massless fields in BTZ black hole background are constructed with the help of the star-product algebra formalism underlying the formulation of 3d higher spin theory. It is shown that a part of higher spin symmetries remains unbroken for special values of the BTZ parameters.

hep-th↗
arXiv2007

Transverse Invariant Higher Spin Fields

It is shown that a symmetric massless bosonic higher-spin field can be described by a traceless tensor field with reduced (transverse) gauge invariance. The Hamiltonian analysis of the transverse gauge invariant higher-spin models is used to control a number of degrees of freedom.

hep-th↗
arXiv2007

Free Field Dynamics in the Generalized AdS (Super)Space

Pure gauge representation for general vacuum background fields (Cartan forms) in the generalized $AdS$ superspace identified with $OSp(L,M)$ is found. This allows us to formulate dynamics of free massless fields in the generalized $AdS$ space-time and to find their (generalized) conformal and higher spin field transformation laws. Generic solution of the field equations is also constructed explicitly. The results are obtained with the aid of the star product realization of ortosymplectic superalgebras.

hep-th↗
arXiv2006

Higher Spin Conformal Currents in Minkowski Space

Using unfolded formulation of free equations for massless fields of all spins we obtain explicit form of higher-spin conformal conserved charges bilinear in 4d massless fields of arbitrary spins.

hep-th↗
arXiv2006

Geometric Formulation for Partially Massless Fields

The manifestly gauge invariant formulation for free symmetric partially massless fields in $(A)dS_d$ is given in terms of gauge connections and linearized curvatures that take values in the irreducible representations of $(o(d-1,2)) o(d,1)$ described by two-row Young tableaux, in which the lengths of the first and second row are, respectively, associated with spin and depth of partial masslessness.

hep-th↗
arXiv2006

Measurement of P_{mu}xi in Polarized Muon Decay

The quantity P_{mu}^{pi}xi, where xi is one of the muon decay parameters and $P_μ^π$ is the degree of muon polarization in pion decay, has been measured. The value P_{mu}^{pi}xi = 1.0003 +- 0.0006 stat. +- 0.0038 syst. was obtained. This result agrees with previous measurements but is over a factor of two more precise. It also agrees with the Standard Model prediction for P_{mu}^{pi}xi and thus leads to restrictions on left-right symmetric models.

hep-ex↗
arXiv2006

Unfolded form of conformal equations in M dimensions and o(M+2)-modules

A constructive procedure is proposed for formulation of linear differential equations invariant under global symmetry transformations forming a semi-simple Lie algebra f. Under certain conditions f-invariant systems of differential equations are shown to be associated with f-modules that are integrable with respect to some parabolic subalgebra of f. The suggested construction is motivated by the unfolded formulation of dynamical equations developed in the higher spin gauge theory and provides a starting point for generalization to the nonlinear case. It is applied to the conformal algebra o(M,2) to classify all linear conformally invariant differential equations in Minkowski space. Numerous examples of conformal equations are discussed from this perspective.

hep-th↗
arXiv2005

Actions, Charges and Off-Shell Fields in the Unfolded Dynamics Approach

Within unfolded dynamics approach, we represent actions and conserved charges as elements of cohomology of the $L_\infty$ algebra underlying the unfolded formulation of a given dynamical system. The unfolded off-shell constraints for symmetric fields of all spins in Minkowski space are shown to have the form of zero curvature and covariant constancy conditions for 1-forms and 0-forms taking values in an appropriate star product algebra. Unfolded formulation of Yang-Mills and Einstein equations is presented in a closed form.

hep-th↗
arXiv2005

Lagrangian Formulation for Free Mixed-Symmetry Bosonic Gauge Fields in (A)dS(d)

Covariant Lagrangian formulation for free bosonic massless fields of arbitrary mixed-symmetry type in (A)dS(d) space-time is presented. The analysis is based on the frame-like formulation of higher-spin field dynamics [1] with higher-spin fields described as p-forms taking values in appropriate modules of the (A)dS(d). The problem of finding free field action is reduced to the analysis of an appropriate differential complex, with the derivation Q associated with the variation of the action. The constructed action exhibits additional gauge symmetries in the flat limit in agreement with the general structure of gauge symmetries for mixed-symmetry fields in Minkowski and (A)dS(d) spaces.

hep-th↗
arXiv2005

Higher Rank Conformal Fields in the $Sp(2M)$ Symmetric Generalized Space-Time

We study various $Sp(2M)$ invariant field equations corresponding to rank $r$ tensor products of the Fock (singleton) representation of $Sp(2M)$. These equations are shown to describe localization on ``branes'' of different dimensions embedded into the generalized space-time $\M_M$ with matrix (i.e., ``central charge'') coordinates. The case of bilinear tensor product is considered in detail. The conserved currents built from bilinears of rank 1 fields in $\M_M$ are shown to satisfy the field equations of the rank 2 fields in $\M_M$. Also, the rank 2 fields in $\M_M$ are shown to be equivalent to the rank 1 fields in $\M_{2M}$.

hep-th↗
arXiv2005

Measurement of the Muon Decay Parameter delta

The muon decay parameter delta has been measured by the TWIST collaboration. We find delta = 0.74964 +- 0.00066(stat.) +- 0.00112(syst.), consistent with the Standard Model value of 3/4. This result implies that the product Pmuxi of the muon polarization in pion decay, Pmu, and the muon decay parameter xi falls within the 90% confidence interval 0.9960 < Pmuxi < xi < 1.0040. It also has implications for left-right-symmetric and other extensions of the Standard Model.

hep-ex↗
arXiv2005

Higher Spin Superalgebras in any Dimension and their Representations

Fock module realization for the unitary singleton representations of the $d-1$ dimensional conformal algebra $o(d-1,2)$, which correspond to the spaces of one-particle states of massless scalar and spinor in $d-1$ dimensions, is given. The pattern of the tensor product of a pair of singletons is analyzed in any dimension. It is shown that for $d>3$ the tensor product of two boson singletons decomposes into a sum of all integer spin totally symmetric massless representations in $AdS_d$, the tensor product of boson and fermion singletons gives a sum of all half-integer spin symmetric massless representations in $AdS_d$, and the tensor product of two fermion singletons in $d>4$ gives rise to massless fields of mixed symmetry types in $AdS_d$ depicted by Young tableaux with one row and one column together with certain totally antisymmetric massive fields. In the special case of $o(2,2)$, tensor products of 2d massless scalar and/or spinor modules contain infinite sets of 2d massless conformal fields of different spins. The obtained results extend the 4d result of Flato and Fronsdal \cite{FF} to any dimension and provide a nontrivial consistency check for the recently proposed higher spin model in $AdS_d$ \cite{d}. We define a class of higher spin superalgebras which act on the supersingleton and higher spin states in any dimension. For the cases of $AdS_3$, $AdS_4$, and $AdS_5$ the isomorphisms with the higher spin superalgebras defined earlier in terms of spinor generating elements are established.

hep-th↗
arXiv2004

On Dual Formulation for Higher Spin Gauge Fields in $(A)dS_d$

We obtain dual actions for spin $s \geq 2$ massless fields in $(A)dS_d$ by solving different algebraic constraints in the same first-order theory. Flat space dual higher spin actions obtained by Boulanger, Cnockaert and Henneaux \cite{BH} by solving differential constraints are shown to result from our formulation in a sort of quasi-classical approximation for the flat limit. The case of $s=2$ is considered in detail.

hep-th↗