127 research outputs found
On gravitational interactions for massive higher spins in
In this paper we investigate gravitational interactions of massive higher
spin fields in three dimensional space with arbitrary value of
cosmological constant including flat Minkowski space. We use frame-like gauge
description for such massive fields adopted to three-dimensional case. At
first, we carefully analyze the procedure of switching on gravitational
interactions in the linear approximation on the example of massive spin-3 field
and then proceed with the generalization to the case of arbitrary integer spin
field. As a result we construct a cubic interaction vertex linear in spin-2
field and quadratic in higher spin field on background. As in the
massless case the vertex does not contain any higher derivative corrections to
the Lagrangian and/or gauge transformations. Thus, even after switching on
gravitational interactions, one can freely consider any massless or partially
massless limits as well as the flat one.Comment: 21 pages. Some clarifications and 1 new reference added. Version to
appear in the J.Phys.A special volume on "Higher Spin Theories and AdS/CFT"
edited by Matthias Gaberdiel and Mikhail Vasilie
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.Comment: 17 pages, v2: clarifications added, misprints corrected; v3: minor
changes, typos correcte
Mixed-symmetry massive fields in AdS(5)
Free mixed-symmetry arbitrary spin massive bosonic and fermionic fields
propagating in AdS(5) are investigated. Using the light-cone formulation of
relativistic dynamics we study bosonic and fermionic fields on an equal
footing. Light-cone gauge actions for such fields are constructed. Various
limits of the actions are discussed.Comment: v3: 24 pages, LaTeX-2e; typos corrected, footnote 7 and 2 references
added, published in Class. Quantum Gra
Cooperative Recombination of a Quantized High-Density Electron-Hole Plasma
We investigate photoluminescence from a high-density electron-hole plasma in
semiconductor quantum wells created via intense femtosecond excitation in a
strong perpendicular magnetic field, a fully-quantized and tunable system. At a
critical magnetic field strength and excitation fluence, we observe a clear
transition in the band-edge photoluminescence from omnidirectional output to a
randomly directed but highly collimated beam. In addition, changes in the
linewidth, carrier density, and magnetic field scaling of the PL spectral
features correlate precisely with the onset of random directionality,
indicative of cooperative recombination from a high density population of free
carriers in a semiconductor environment
BRST approach to Lagrangian formulation of bosonic totally antisymmeric tensor fields in curved space
We apply the BRST approach, previously developed for higher spin field
theories, to gauge invariant Lagrangian construction for antisymmetric massive
and massless bosonic fields in arbitrary d-dimensional curved space. The
obtained theories are reducible gauge models both in massless and massive cases
and the order of reducibility grows with the value of the rank of the
antisymmetric field. In both the cases the Lagrangians contain the sets of
auxiliary fields and possess more rich gauge symmetry in comparison with
standard Lagrangian formulation for the antisymmetric fields. This serves
additional demonstration of universality of the BRST approach for Lagrangian
constructions in various field models.Comment: 12 page
Massive Gravity on de Sitter and Unique Candidate for Partially Massless Gravity
We derive the decoupling limit of Massive Gravity on de Sitter in an
arbitrary number of space-time dimensions d. By embedding d-dimensional de
Sitter into d+1-dimensional Minkowski, we extract the physical helicity-1 and
helicity-0 polarizations of the graviton. The resulting decoupling theory is
similar to that obtained around Minkowski. We take great care at exploring the
partially massless limit and define the unique fully non-linear candidate
theory that is free of the helicity-0 mode in the decoupling limit, and which
therefore propagates only four degrees of freedom in four dimensions. In the
latter situation, we show that a new Vainshtein mechanism is at work in the
limit m^2\to 2 H^2 which decouples the helicity-0 mode when the parameters are
different from that of partially massless gravity. As a result, there is no
discontinuity between massive gravity and its partially massless limit, just in
the same way as there is no discontinuity in the massless limit of massive
gravity. The usual bounds on the graviton mass could therefore equivalently
well be interpreted as bounds on m^2-2H^2. When dealing with the exact
partially massless parameters, on the other hand, the symmetry at m^2=2H^2
imposes a specific constraint on matter. As a result the helicity-0 mode
decouples without even the need of any Vainshtein mechanism.Comment: 30 pages. Some clarifications and references added. New subsection
'Symmetry and Counting in the Full Theory' added. New appendix 'St\"uckelberg
fields in the Na\"ive approach' added. Matches version published in JCA
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