3,870 research outputs found
Free Field Dynamics in the Generalized AdS (Super)Space
Pure gauge representation for general vacuum background fields (Cartan forms)
in the generalized superspace identified with is found. This
allows us to formulate dynamics of free massless fields in the generalized
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.Comment: Some notes added, corrected typo
Test of the local form of higher-spin equations via AdS/CFT
The local form of higher-spin equations found recently to the second order
[1] is shown to properly reproduce the anticipated correlators for
appropriate boundary conditions. It is argued that consistent
holography for the parity-broken boundary models needs a nontrivial
modification of the bosonic truncation of the original higher-spin theory with
the doubled number of fields, as well as a nonlinear deformation of the
boundary conditions in the higher orders.Comment: 18 pages, Typos and acknowledgement corrected. Misleading notation in
Section 4.2 changed. References correcte
A Higgs Mechanism for Gravity. Part II: Higher Spin Connections
We continue the work of hep-th/0503024 in which gravity is considered as the
Goldstone realization of a spontaneously broken diffeomorphism group. We
complete the discussion of the coset space Diff(d,R)/SO(1,d-1) formed by the
d-dimensional group of analytic diffeomorphisms and the Lorentz group. We find
that this coset space is parameterized by coordinates, a metric and an infinite
tower of higher-spin-like or generalized connections. We then study effective
actions for the corresponding symmetry breaking which gives mass to the higher
spin connections. Our model predicts that gravity is modified at high energies
by the exchange of massive higher spin particles.Comment: 17 pages; discussion on local Poincare invariance and matter currents
added; references adde
Multi-field approach in mechanics of structural solids
We overview the basic concepts, models, and methods related to the
multi-field continuum theory of solids with complex structures. The multi-field
theory is formulated for structural solids by introducing a macrocell
consisting of several primitive cells and, accordingly, by increasing the
number of vector fields describing the response of the body to external
factors. Using this approach, we obtain several continuum models and explore
their essential properties by comparison with the original structural models.
Static and dynamical problems as well as the stability problems for structural
solids are considered. We demonstrate that the multi-field approach gives a way
to obtain families of models that generalize classical ones and are valid not
only for long-, but also for short-wavelength deformations of the structural
solid. Some examples of application of the multi-field theory and directions
for its further development are also discussed.Comment: 25 pages, 18 figure
Charges in nonlinear higher-spin theory
Nonlinear higher-spin equations in four dimensions admit a closed two-form
that defines a gauge-invariant global charge as an integral over a
two-dimensional cycle. In this paper we argue that this charge gives rise to
partitions depending on various lower- and higher-spin chemical potentials
identified with modules of topological fields in the theory. The vacuum
contribution to the partition is calculated to the first nontrivial order for a
solution to higher-spin equations that generalizes AdS4 Kerr black hole of
General Relativity. The resulting partition is non-zero being in parametric
agreement with the ADM-like behavior of a rotating source. The linear response
of chemical potentials to the partition function is also extracted. The
explicit unfolded form of 4d GR black holes is given. An explicit formula
relating asymptotic higher-spin charges expressed in terms of the generalized
higher-spin Weyl tensor with those expressed in terms of Fronsdal fields is
obtained.Comment: 23 pages; V3: typos corrected; references and acknowledgement added;
example of the topological contribution to spin-4 charge added; new Section
3.1 added establishing relation of our construction for asymptotic charges
with the canonical one. Version published in JHE
Lorentz covariant form of extended higher-spin equations
The extension of nonlinear higher-spin equations in d=4 proposed in
[arXiv:1504.07289] for the construction of invariant functional is shown to
respect local Lorentz symmetry. The equations are rewritten in a manifestly
Lorentz covariant form resulting from some Stueckelberg-like field
transformation. We also show that the two field-independent central terms
entering higher-spin equations which are not entirely fixed by the consistency
alone get fixed unambiguously by the requirement of Lorentz symmetry. One of
the important advantages of the proposed approach demonstrated in the paper is
the remarkable simplification of the perturbative analysis.Comment: V2: 20 pages, typos corrected, references added. Version published in
JHE
Deformed Oscillator Algebras and Higher-Spin Gauge Interactions of Matter Fields in 2+1 Dimensions
We formulate a non-linear system of equations which describe higher-spin
gauge interactions of massive matter fields in 2+1 dimensional space-time and
explain some properties of the deformed oscillator algebra which underlies this
formulation. In particular we show that the parameter of mass of matter
fields is related to the deformation parameter in this algebra.Comment: LaTex, 12 pages, no figures; Invited talk at the International
Seminar Supersymmetry and Quantum Field Theory dedicated to the memory of
Dmitrij V. Volkov; Kharkov, January 1997; to appear in the proceeding
Superbroad Component in Emission Lines of SS 433
We have detected new components in stationary emission lines of SS 433; these
are the superbroad components that are low-contrast substrates with a width of
2000--2500 km s-1 in He I and H and 4000--5000 km s-1 in
He II . Based on 44 spectra taken during four years of
observations from 2003 to 2007, we have found that these components in the He
II and He I lines are eclipsed by the donor star; their behavior with
precessional and orbital phases is regular and similar to the behavior of the
optical brightness of SS 433. The same component in H shows neither
eclipses nor precessional variability. We conclude that the superbroad
components in the helium and hydrogen lines are different in origin. Electron
scattering is shown to reproduce well the superbroad component of H at a
gas temperature of 20--35 kK and an optical depth for Thomson scattering 0.25--0.35. The superbroad components of the helium lines are probably
formed in the wind from the supercritical accretion disk. We have computed a
wind model based on the concept of Shakura-Sunyaev supercritical disk
accretion. The main patterns of the He II line profiles are well reproduced in
this model: not only the appearance of the superbroad component but also the
evolution of the central two-component part of the profile of this line during
its eclipse by the donor star can be explained.Comment: 17 pages, 13 figures, 2 tables, published in Astronomy Letters, 2013,
vol. 39, N 12, pp. 826 - 84
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