1,720 research outputs found
Letter from G.W. Johnson to James B. Finley
The New Plymouth Division, Sons of Temperance, has erected a building which they badly needed. Unfortunately, the division has not been able to fully cover the cost. As a last resort, members are soliciting aid from other divisions. They ask for Finley\u27s help to raise the money. Abstract Number - 1199https://digitalcommons.owu.edu/finley-letters/2179/thumbnail.jp
Generalized Complex Spherical Harmonics, Frame Functions, and Gleason Theorem
Consider a finite dimensional complex Hilbert space \cH, with dim(\cH)
\geq 3, define \bS(\cH):= \{x\in \cH \:|\: ||x||=1\}, and let \nu_\cH be
the unique regular Borel positive measure invariant under the action of the
unitary operators in \cH, with \nu_\cH(\bS(\cH))=1. We prove that if a
complex frame function f : \bS(\cH)\to \bC satisfies f \in \cL^2(\bS(\cH),
\nu_\cH), then it verifies Gleason's statement: There is a unique linear
operator A: \cH \to \cH such that for every u \in
\bS(\cH). is Hermitean when is real. No boundedness requirement is
thus assumed on {\em a priori}.Comment: 9 pages, Accepted for publication in Ann. H. Poincar\'
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Precipitation and latent heating distributions from satellite passive microwave radiometry. Part I: improved method and uncertainties
A revised Bayesian algorithm for estimating surface rain rate, convective rain proportion, and latent heating profiles from satellite-borne passive microwave radiometer observations over ocean backgrounds is described. The algorithm searches a large database of cloud-radiative model simulations to find cloud profiles that are radiatively consistent with a given set of microwave radiance measurements. The properties of these radiatively consistent profiles are then composited to obtain best estimates of the observed properties. The revised algorithm is supported by an expanded and more physically consistent database of cloud-radiative model simulations. The algorithm also features a better quantification of the convective and nonconvective contributions to total rainfall, a new geographic database, and an improved representation of background radiances in rain-free regions. Bias and random error estimates are derived from applications of the algorithm to synthetic radiance data, based upon a subset of cloud-resolving model simulations, and from the Bayesian formulation itself. Synthetic rain-rate and latent heating estimates exhibit a trend of high (low) bias for low (high) retrieved values. The Bayesian estimates of random error are propagated to represent errors at coarser time and space resolutions, based upon applications of the algorithm to TRMM Microwave Imager (TMI) data. Errors in TMI instantaneous rain-rate estimates at 0.5°-resolution range from approximately 50% at 1 mm h−1 to 20% at 14 mm h−1. Errors in collocated spaceborne radar rain-rate estimates are roughly 50%–80% of the TMI errors at this resolution. The estimated algorithm random error in TMI rain rates at monthly, 2.5° resolution is relatively small (less than 6% at 5 mm day−1) in comparison with the random error resulting from infrequent satellite temporal sampling (8%–35% at the same rain rate). Percentage errors resulting from sampling decrease with increasing rain rate, and sampling errors in latent heating rates follow the same trend. Averaging over 3 months reduces sampling errors in rain rates to 6%–15% at 5 mm day−1, with proportionate reductions in latent heating sampling errors
Effect of “starter” N and P on nodulation and seed yield in field pea, lentil, and chickpea in semiarid Canadian prairies
Non-Peer Reviewe
Supersymmetry and Stationary Solutions in Dilaton-Axion Gravity
New stationary solutions of -dimensional dilaton-axion gravity are
presented, which correspond to the charged Taub-NUT and Israel-Wilson-Perjes
(IWP) solutions of Einstein-Maxwell theory. The charged axion-dilaton Taub-NUT
solutions are shown to have a number of interesting properties: i) manifest
symmetry, ii) an infinite throat in an extremal limit, iii) the
throat limit coincides with an exact CFT construction.
The IWP solutions are shown to admit supersymmetric Killing spinors, when
embedded in supergravity. This poses a problem for the interpretation
of supersymmetric rotating solutions as physical ground states. In the context
of -dimensional geometry, we show that dimensionally lifted versions of the
IWP solutions are dual to certain gravitational waves in string theory.Comment: 23 pages (latex), SU-ITP-94-12, UMHEP-407, QMW-PH-94-1
Recoil correction to the ground state energy of hydrogenlike atoms
The recoil correction to the ground state energy of hydrogenlike atoms is
calculated to all orders in \alpha Z in the range Z = 1-110. The nuclear size
corrections to the recoil effect are partially taken into account. In the case
of hydrogen, the relativistic recoil correction beyond the Salpeter
contribution and the nonrelativistic nuclear size correction to the recoil
effect, amounts to -7.2(2) kHz. The total recoil correction to the ground state
energy in hydrogenlike uranium (^{238}U^{91+}) constitutes 0.46 eV.Comment: 16 pages, 1 figure (eps), Latex, submitted to Phys.Rev.
Exact SU(2)*U(1) Stringy Black Holes
Extreme magnetic dilaton black holes are promoted to exact solutions of
heterotic string theory with unbroken supersymmetry. With account taken of
alpha' corrections this is accomplished by supplementing the known solutions
with SU(2) Yang-Mills vectors and scalars in addition to the already existing
Abelian U(1) vector field. The solution has a simple analytic form and includes
multi-black-holes. The issue of exactness of other black-hole-type solutions,
including extreme dilaton electrically charged black holes and Taub-NUT
solutions is discussed.Comment: 10 pages, SU-ITP-94-27 and QMW-PH-94-34 (version accepted for
publication in Phys. Rev., contains a discussion of (4.1) supersymmetry of
the black hole sigma model
Branes, Rings and Matrix Models in Minimal (Super)string Theory
We study both bosonic and supersymmetric (p,q) minimal models coupled to
Liouville theory using the ground ring and the various branes of the theory.
From the FZZT brane partition function, there emerges a unified, geometric
description of all these theories in terms of an auxiliary Riemann surface
M_{p,q} and the corresponding matrix model. In terms of this geometric
description, both the FZZT and ZZ branes correspond to line integrals of a
certain one-form on M_{p,q}. Moreover, we argue that there are a finite number
of distinct (m,n) ZZ branes, and we show that these ZZ branes are located at
the singularities of M_{p,q}. Finally, we discuss the possibility that the
bosonic and supersymmetric theories with (p,q) odd and relatively prime are
identical, as is suggested by the unified treatment of these models.Comment: 72 pages, 3 figures, improved treatment of FZZT and ZZ branes, minor
change
The Enhancon, Black Holes, and the Second Law
We revisit the physics of five-dimensional black holes constructed from D5-
and D1-branes and momentum modes in type IIB string theory compactified on K3.
Since these black holes incorporate D5-branes wrapped on K3, an enhancon locus
appears in the spacetime geometry. With a `small' number of D1-branes, the
entropy of a black hole is maximised by including precisely half as many
D5-branes as there are D1-branes in the black hole. Any attempts to introduce
more D5-branes, and so reduce the entropy, are thwarted by the appearance of
the enhancon locus above the horizon, which then prevents their approach. The
enhancon mechanism thereby acts to uphold the Second Law of Thermodynamics.
This result generalises: For each type of bound state object which can be made
of both types of brane, we show that a new type of enhancon exists at
successively smaller radii in the geometry, again acting to prevent any
reduction of the entropy just when needed. We briefly explore the appearance of
the enhancon in the black hole interior.Comment: 22 pages, 2 figures, latex, epsfig (v2: Fixed trivial typos.
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