4,506 research outputs found
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
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
Interferometry of hyper-Rayleigh scattering by inhomogeneous thin films
The use of specific symmetry properties of the optical second-harmonic
generation (the s,s-exclusion rule) has allowed us to observe high-contrast
hyper-Rayleigh interference patterns in a completely diffuse light - an effect
having no analog in case of linear (Rayleigh) scattering.Comment: 8 pages, 3 figure
On -dominance, shift symmetry and spin locality in higher-spin theory
The paper aims at the qualitative criterion of higher-spin locality.
Perturbative analysis of the Vasiliev equations gives rise to the so-called
-dominated non-localities which nevertheless disappear from interaction
vertices leaving the final result spin-local in all known cases. This has led
one to the -- dominance conjecture that suggests universality of the
observed cancellations. Here we specify conditions which include observation of
the higher-spin shift symmetry and prove validity of this recently proposed
conjecture. We also define a class of spin-local and shift-symmetric field
redefinitions which is argued to be the admissible one with respect to
spin-locality.Comment: 31 page
On interaction of symmetric higher-spin gauge fields
We show that the recently proposed equations for holomorphic sector of
higher-spin theory in , also known as chiral, can be naturally extended to
describe interacting symmetric higher-spin gauge fields in any dimension. This
is achieved with the aid of Vasiliev's off-shell higher-spin algebra. The
latter contains ideal associated to traces that has to be factored out in order
to set the equations on-shell. To identify the ideal in interactions we observe
the global that underlies it to all orders. The field dependent
generators are found in closed form and appear to be remarkably simple. The
traceful higher-spin vertices are analyzed against locality and shown to be
all-order space-time spin-local in the gauge sector, as well as spin-local in
the Weyl sector. The vertices are found manifestly in the form of curious
integrals over hypersimplices. We also extend to any the earlier observed
in higher-spin shift symmetry known to be tightly related to
spin-locality.Comment: 34 page
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
Correcting for Distortions due to Ionization in the STAR TPC
Physics goals of the STAR Experiment at RHIC in recent (and future) years
drive the need to operate the STAR TPC at ever higher luminosities, leading to
increased ionization levels in the TPC gas. The resulting ionic space charge
introduces field distortions in the detector which impact tracking performance.
Further complications arise from ionic charge leakage into the main TPC volume
from the high gain anode region. STAR has implemented corrections for these
distortions based on measures of luminosity, which we present here.
Additionally, we highlight a novel approach to applying the corrections on an
event-by-event basis applicable in conditions of rapidly varying ionization
sources.Comment: 6 pages, 7 figures, proceedings of the Workshop on Tracking in High
Multiplicity Environments (TIME 05) in Zurich, Switzerland, submitted to
Nucl. Instr. and Meth.
- …