546 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
Supersymmetric Distributions, Hilbert Spaces of Supersymmetric Functions and Quantum Fields
The recently investigated Hilbert-Krein and other positivity structures of
the superspace are considered in the framework of superdistributions. These
tools are applied to problems raised by the rigorous supersymmetric quantum
field theory.Comment: 24 page
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
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 15â30 ÎŒm 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
Steroid concentrations in atopic dermatitis patients: Reduced plasma DHEAS and increased cortisone levels.
Atopic dermatitis (AD) is a chronically relapsing inflammatory skin disease, which is characterized by a disrupted epidermal barrier function present both in affected skin and in non-affected skin. Mainly glucocorticosteroids were used in topical and systemic atopy treatments because of their potent anti-inflammatory effects, unfortunately with strong side effects. In this study we determined that 2 out of 16 steroids were significantly different in healthy volunteers vs AD-patients. Cortisone, which is higher in AD-patients plasma, is a direct precursor of the bioactive corticosteroid cortisol, which just displays a higher tendency and is known for its potent anti-inflammatory effects. In addition a tendency of reduced levels of the anti-inflammatory ER ligand estrone was found in AD-patients. DHEA is a precursor of testosterone, its levels just display a lower tendency in male AD-patients, while its sulfonation metabolite DHEAS is lower in male and female AD-patients. We found and conclude that altered steroid levels in the plasma of AD-patients indicate altered vitamin D signaling (based on reduced DHEA sulfonation) and increased feedback for anti-inflammatory signaling (increased levels of cortisone) present in AD-patients. This article is protected by copyright. All rights reserved
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.
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
Untersuchungen zum Gaswechsel der Rebe I. EinfluĂ von Temperatur, Blattalter und Tageszeit auf Nettophotosynthese und Transpiration
An verschiedenen Rebsorten wurde unter Laborbedingungen (30 klx, 50 % ) der EinfluĂ von Temperatur, Blattalter und Tageszeit auf die Nettophotosyntheserate (NPR) und Transpirationsrate (TR) an GewĂ€chshauspflanzen ermittelt. Das Optimum der NPR lag bei 25 °C, wĂ€hrend die TR von 10 °C bis 30 °C annĂ€hernd linear anstieg.Die höchste NPR hatten gerade ausgewachsene BlĂ€tter; Ă€ltere BlĂ€tter zeigten eine etwas geringere, jĂŒngere eine deutlich verminderte NPR. Die VerhĂ€ltnisse bei der TR waren Ă€hnlich, aber weniger ausgeprĂ€gt und zu den jĂŒngeren BlĂ€ttern hin verschoben.Bei trocken kultivierten Pflanzen kam es im Laufe des Tages zu einer starken Reduktion der NPR and TR um etwa 2/a der Werte des Vormittags, nicht dagegen bei ausreichender Wasserversorgung.Investigations on gas exchange in grapevine I. Influence of temperature, leaf age and daytime on net photosynthesis and transpirationThe influence of temperature, leaf age and daytime on the rates of net photosynthesis and transpiration was measured under constant environmental conditions in greenhouse-grown plants of different varieties.The temperature optimum of net photosynthesis was at 25 °C whereas transpiration increased nearly linear from 10 °C to 30 °C.The highest rates of net photosynthesis possessed just fully grown leaves; older leaves showed a minor, younger leaves a more pronounced reduction. The pattern of transpiration rates was nearly the same, but not that distinct.Plants grown under drought conditions reduced their rates of net photosynthesis and transpiration during daytime very strongly (by 2/3 of the rates early in the morning). whereas in watered plants this influence could not be observed
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