4,743 research outputs found
Properties of air and combustion products of fuels with air
Thermodynamic and transport properties include ratio of specific heats, molecular weight, viscosity, heat capacity, thermal conductivity, and Prandtl number. Properties are calculated from 300 to 2500 degrees K and for pressures of three and ten atmospheres
A Manifestly Gauge-Invariant Approach to Quantum Theories of Gauge Fields
In gauge theories, physical histories are represented by space-time
connections modulo gauge transformations. The space of histories is thus
intrinsically non-linear. The standard framework of constructive quantum field
theory has to be extended to face these {\it kinematical} non-linearities
squarely. We first present a pedagogical account of this problem and then
suggest an avenue for its resolution.Comment: 27 pages, CGPG-94/8-2, latex, contribution to the Cambridge meeting
proceeding
Edmund D. Lewandowski Collection - Accession 1522
The Edmund D. Lewandowski Collection consists of correspondence, notes, emails, newspaper clippings, exhibit catalogues, a signed print, and other material relating to Edmund D. Lewandowski (1914-1998), artist and Chairman of the Winthrop Art Department from 1973-1984.https://digitalcommons.winthrop.edu/manuscriptcollection_findingaids/2544/thumbnail.jp
Decoherence-driven Cooling of a Degenerate Spinor Bose Gas
We investigate the relationship between the coherence of a partially
Bose-condensed spinor gas and its temperature. We observe cooling of the normal
component driven by decoherence as well the effect of temperature on
decoherence rates.Comment: 4 pages, 2 figure
The Mystery of the Ramsey Fringe that Didn't Chirp
We use precision microwave spectroscopy of magnetically trapped, ultra-cold
87Rb to characterize intra- and inter-state density correlations. The cold
collision shifts for both normal and condensed clouds are measured. The results
verify the presence of the sometimes controversial "factors of two", in
normal-cloud mean-field energies, both within a particular state and between
two distinct spin species. One might expect that as two spin species decohere,
the inter-state factor of two would revert to unity, but the associated
frequency chirp one naively expects from such a trend is not observed in our
data.Comment: Proceedings of the 18th International Conference on Atomic Physics
(ICAP 2002
Geometry of Generic Isolated Horizons
Geometrical structures intrinsic to non-expanding, weakly isolated and
isolated horizons are analyzed and compared with structures which arise in
other contexts within general relativity, e.g., at null infinity. In
particular, we address in detail the issue of singling out the preferred
normals to these horizons required in various applications. This work provides
powerful tools to extract invariant, physical information from numerical
simulations of the near horizon, strong field geometry. While it complements
the previous analysis of laws governing the mechanics of weakly isolated
horizons, prior knowledge of those results is not assumed.Comment: 37 pages, REVTeX; Subsections V.B and V.C moved to a new Appenedix to
improve the flow of main argument
Multi-frequency observations and spectral analysis of two gigahertz-peaked spectra pulsars
We report the multi-frequency observations of two pulsars: J1740+1000 and
B1800-21, using the Giant Metrewave Radio Telescope and the Green Bank
Telescope. The main aim of these observations was to estimate the flux density
spectrum of these pulsars, as both of them were previously reported to exhibit
gigahertz-peaked spectra. J1740+1000 is a young pulsar far from the Galactic
plane and the interpretation of its spectrum was inconclusive in the light of
the recent flux density measurements. Our result supports the gigahertz-peaked
interpretation of the PSR J1740+1000 spectrum. B1800-21 is a Vela-like pulsar
near the W30 complex, whose spectrum exhibit a significant change between 2012
and 2014 year. Our analysis shows that the current shape of the spectrum is
similar to that observed before 2009 and confirms that the observed spectral
change happen in a time-scale of a few years.Comment: 9 pages, 7 figure
Quasi-local rotating black holes in higher dimension: geometry
With a help of a generalized Raychaudhuri equation non-expanding null
surfaces are studied in arbitrarily dimensional case. The definition and basic
properties of non-expanding and isolated horizons known in the literature in
the 4 and 3 dimensional cases are generalized. A local description of horizon's
geometry is provided. The Zeroth Law of black hole thermodynamics is derived.
The constraints have a similar structure to that of the 4 dimensional spacetime
case. The geometry of a vacuum isolated horizon is determined by the induced
metric and the rotation 1-form potential, local generalizations of the area and
the angular momentum typically used in the stationary black hole solutions
case.Comment: 32 pages, RevTex
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