4,523 research outputs found
How massless are massless fields in
Massless fields of generic Young symmetry type in space are analyzed.
It is demonstrated that in contrast to massless fields in Minkowski space whose
physical degrees of freedom transform in irreps of algebra,
massless mixed symmetry fields reduce to a number of irreps of
algebra. From the field theory perspective this means that not every massless
field in flat space admits a deformation to 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 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 .Comment: 23 pages, LaTeX, a few typos correcte
An AdS_3 Dual for Minimal Model CFTs
We propose a duality between the 2d W_N minimal models in the large N 't
Hooft limit, and a family of higher spin theories on AdS_3. The 2d CFTs can be
described as WZW coset models, and include, for N=2, the usual Virasoro unitary
series. The dual bulk theory contains, in addition to the massless higher spin
fields, two complex scalars (of equal mass). The mass is directly related to
the 't Hooft coupling constant of the dual CFT. We give convincing evidence
that the spectra of the two theories match precisely for all values of the 't
Hooft coupling. We also show that the RG flows in the 2d CFT agree exactly with
the usual AdS/CFT prediction of the gravity theory. Our proposal is in many
ways analogous to the Klebanov-Polyakov conjecture for an AdS_4 dual for the
singlet sector of large N vector models.Comment: 33 pages LaTe
Free totally (anti)symmetric massless fermionic fields in d-dimensional anti-de Sitter space
Free massless fermionic fields of arbitrary spins corresponding to
totally (anti)symmetric tensor-spinor representations of the compact
subgroup and in -dimensional anti-de Sitter space are investigated. We
propose the free equations of motion, subsidiary conditions and corresponding
gauge transformations for such fields. The equations obtained are used to
derive the lowest energy values for the above-mentioned representations. A new
representation for equations of motion and gauge transformations in terms of
generators of anti-de Sitter group is found. It is demonstrated
that in contrast to the symmetric case the gauge parameter of the antisymmetric
massless field is also a massless field.Comment: 9 pages, LaTe
Higher Spin Fields in Siegel Space, Currents and Theta Functions
Dynamics of four-dimensional massless fields of all spins is formulated in
the Siegel space of complex symmetric matrices. It is shown that
the unfolded equations of free massless fields, that have a form of
multidimensional Schrodinger equations, naturally distinguish between positive-
and negative-frequency solutions of relativistic field equations, i.e.
particles and antiparticles. Multidimensional Riemann theta functions are shown
to solve massless field equations in the Siegel space. We establish the
correspondence between conserved higher-spin currents in four-dimensional
Minkowski space and those in the ten-dimensional matrix space. It is shown that
global symmetry parameters of the current in the matrix space should be
singular to reproduce a nonzero current in Minkowski space. The \D-function
integral evolution formulae for 4d massless fields in the Fock-Siegel space are
obtained. The generalization of the proposed scheme to higher dimensions and
systems of higher ranks is considered.Comment: LaTeX, 38 pages, v.3: clarifications, acknowledgements and references
added, typos corrected, v.4: more comments and references added, typos
corrected, the version to appear in JHE
Mixed-symmetry massless gauge fields in AdS(5)
Free AdS(5) mixed-symmetry massless bosonic and fermionic gauge fields of
arbitrary spins are described by using su(2,2) spinor language. Manifestly
covariant action functionals are constructed and field equations are derived.Comment: 13 pages; v2: title changed, typos corrected, minor changes,
reference added; v3: minor changes, published versio
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.Comment: LaTeX, 10 pages. Corrected typo
Shadows, currents and AdS fields
Conformal totally symmetric arbitrary spin currents and shadow fields in flat
space-time of dimension greater than or equal to four are studied. Gauge
invariant formulation for such currents and shadow fields is developed. Gauge
symmetries are realized by involving the Stueckelberg fields. Realization of
global conformal boost symmetries is obtained. Gauge invariant differential
constraints for currents and shadow fields are obtained. AdS/CFT correspondence
for currents and shadow fields and the respective normalizable and
non-normalizable solutions of massless totally symmetric arbitrary spin AdS
fields is studied. The bulk fields are considered in modified de Donder gauge
that leads to decoupled equations of motion. We demonstrate that leftover
on-shell gauge symmetries of bulk fields correspond to gauge symmetries of
boundary currents and shadow fields, while the modified de Donder gauge
conditions for bulk fields correspond to differential constraints for boundary
conformal currents and shadow fields. Breaking conformal symmetries, we find
interrelations between the gauge invariant formulation of the currents and
shadow fields and the gauge invariant formulation of massive fields.Comment: v3: 31 pages, RevTeX4. Appendix D devoted to modified de Donder gauge
in AdS(d+1) x S(d+1) added. Footnotes 10, 21 added. Typos correcte
Lagrange Anchor for Bargmann-Wigner equations
A Poincare invariant Lagrange anchor is found for the non-Lagrangian
relativistic wave equations of Bargmann and Wigner describing free massless
fields of spin s > 1/2 in four-dimensional Minkowski space. By making use of
this Lagrange anchor, we assign a symmetry to each conservation law.Comment: A contribution to Proceedings of the XXXI Workshop on the Geometric
Methods in Physic
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