629 research outputs found
Towards a quantum field theory of primitive string fields
We denote generating functions of massless even higher spin fields "primitive
string fields" (PSF's). In an introduction we present the necessary definitions
and derive propagators and currents of these PDF's on flat space. Their
off-shell cubic interaction can be derived after all off-shell cubic
interactions of triplets of higher spin fields have become known [2],[3]. Then
we discuss four-point functions of any quartet of PSF's. In subsequent sections
we exploit the fact that higher spin field theories in are
determined by AdS/CFT correspondence from universality classes of critical
systems in dimensional flat spaces. The O(N) invariant sectors of the O(N)
vector models for play for us the role of "standard
models", for varying , they contain e.g. the Ising model for N=1 and the
spherical model for . A formula for the masses squared that break
gauge symmetry for these O(N) classes is presented for d = 3. For the PSF on
space it is shown that it can be derived by lifting the PSF on flat space
by a simple kernel which contains the sum over all spins. Finally we use an
algorithm to derive all symmetric tensor higher spin fields. They arise from
monomials of scalar fields by derivation and selection of conformal
(quasiprimary) fields. Typically one monomial produces a multiplet of spin
conformal higher spin fields for all , they are distinguished by
their anomalous dimensions (in ) or by their mass (in ). We sum
over these multiplets and the spins to obtain "string type fields", one for
each such monomial.Comment: 16 pages,Late
ST-HM equipment consolidation
In general all kind of equipment must be maintained if it is to fulfil its function for a useful life. This can be achieved using one of the four key maintenance strategies - on failure maintenance, fixed time maintenance, condition based maintenance and design out maintenance. Each of these strategies has a place within an optimised maintenance plan. The first three maintenance strategies are mostly applied and implemented in the various ST maintenance plans. The fourth strategy in contrast, design out maintenance (also referred to as equipment consolidation / replacement), is rather applied in an ad-hoc strategy than in an organised way. This paper shall outline the general factors that must be considered in order to implement design out maintenance. Furthermore this paper shall demonstrate a possible approach for the application of design out maintenance regarding transport and handling equipment
Exact solvability of the Calogero and Sutherland models
Translationally invariant symmetric polynomials as coordinates for n-body problems with identical particles are proposed. It is shown that in those coordinates the Calogero and Sutherland n-body Hamiltonians after appropriate gauge transformations can be presented as a {\it quadratic} polynomial in the generators of the algebra sl_n in finite-dimensional degenerate representations. The exact solvability of these models follows from the existence of the infinite flags of such representation spaces preserved by above Hamiltonians
Exactly solvable potentials of Calogero type for q-deformed Coxeter groups
We establish that by parameterizing the configuration space of a
one-dimensional quantum system by polynomial invariants of q-deformed Coxeter
groups it is possible to construct exactly solvable models of Calogero type. We
adopt the previously introduced notion of solvability which consists of
relating the Hamiltonian to finite dimensional representation spaces of a Lie
algebra. We present explicitly the -case for which we construct the
potentials by means of suitable gauge transformations.Comment: 22 pages Late
Multiple algebraisations of an elliptic Calogero-Sutherland model
Recently, Gomez-Ullate et al. (1) have studied a particular N-particle
quantum problem with an elliptic function potential supplemented by an external
field. They have shown that the Hamiltonian operator preserves a finite
dimensional space of functions and as such is quasi exactly solvable (QES). In
this paper we show that other types of invariant function spaces exist, which
are in close relation to the algebraic properties of the elliptic functions.
Accordingly, series of new algebraic eigenfunctions can be constructed.Comment: 9 Revtex pages, 3 PS-figures; Summary, abstract and conclusions
extende
Structural motifs of pre-nucleation clusters
Structural motifs of pre-nucleation clusters prepared in single, optically
levitated supersaturated aqueous aerosol microparticles containing CaBr2 as a
model system are reported. Cluster formation is identified by means of X-ray
absorption in the Br K-edge regime. The salt concentration beyond the
saturation point is varied by controlling the humidity in the ambient
atmosphere surrounding the 15–30 μm microdroplets. This leads to the formation
of metastable supersaturated liquid particles. Distinct spectral shifts in
near-edge spectra as a function of salt concentration are observed, in which
the energy position of the Br K-edge is red-shifted by up to 7.1 ± 0.4 eV if
the dilute solution is compared to the solid. The K-edge positions of
supersaturated solutions are found between these limits. The changes in
electronic structure are rationalized in terms of the formation of pre-
nucleation clusters. This assumption is verified by spectral simulations using
first-principle density functional theory and molecular dynamics calculations,
in which structural motifs are considered, explaining the experimental
results. These consist of solvated CaBr2 moieties, rather than building blocks
forming calcium bromide hexahydrates, the crystal system that is formed by
drying aqueous CaBr2 solutions
Basis States for Relativistic, Dynamically-Entangled Particles
In several recent papers on entanglement in relativistic quantum systems and
relativistic Bell's inequalities, relativistic Bell-type two-particle states
have been constructed in analogy to non-relativistic states. These
constructions do not have the form suggested by relativistic invariance of the
dynamics. Two relativistic formulations of Bell-type states are shown for
massive particles, one using the standard Wigner spin basis and one using the
helicity basis. The construction hinges on the use of Clebsch-Gordan
coefficients of the Poincar\'e group to reduce the direct product of two
unitary irreducible representations (UIRs) into a direct sum of UIRs.Comment: 19 pages, three tables, revte
Local Interactions of Higher-Spin Potentials That are Gauge Invariant in Linear Approximation
We study connected Wightman functions of conserved currents, each of
which is formed from a scalar field and has even spin . The UV
divergence of this vertex function is regularized by the analytic continuation
in the space dimension . We evaluate the residue
of only, which is a local interaction Lagrangian density and
gauge invariant in linearComment: Talk given at Group XXVII Yerevan, Armenia, August 13-29, 2008, v.2
published in Yadernaya Fizika 73 (2010) 518-52
Gravitation on a Homogeneous Domain
Among all plastic deformations of the gravitational Lorentz vacuum \cite{wr1}
a particular role is being played by conformal deformations. These are
conveniently described by using the homogeneous space for the conformal group
SU(2,2)/S(U(2)x U(2)) and its Shilov boundary - the compactified Minkowski
space \tilde{M} [1]. In this paper we review the geometrical structure involved
in such a description. In particular we demonstrate that coherent states on the
homogeneous Kae}hler domain give rise to Einstein-like plastic conformal
deformations when extended to \tilde{M} [2].Comment: 10 pages, 1 figure; four misprints in the original version corrected:
one lacking closing parenthesis, two letters, and an overall sign in front of
the primitive function on p.
The minimal conformal O(N) vector sigma model at d=3
For the minimal O(N) sigma model, which is defined to be generated by the
O(N) scalar auxiliary field alone, all n-point functions, till order 1/N
included, can be expressed by elementary functions without logarithms.
Consequently, the conformal composite fields of m auxiliary fields possess at
the same order such dimensions, which are m times the dimension of the
auxiliary field plus the order of differentiation.Comment: 15 page
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