7,351 research outputs found
Bell's Theorem from Moore's Theorem
It is shown that the restrictions of what can be inferred from
classically-recorded observational outcomes that are imposed by the no-cloning
theorem, the Kochen-Specker theorem and Bell's theorem also follow from
restrictions on inferences from observations formulated within classical
automata theory. Similarities between the assumptions underlying classical
automata theory and those underlying universally-unitary quantum theory are
discussed.Comment: 12 pages; to appear in Int. J. General System
Neutron activation analysis traces copper artifacts to geographical point of origin
Impurities remaining in the metallic copper are identified and quantified by spectrographic and neutron activation analysis. Determination of the type of ore used for the copper artifact places the geographic point of origin of the artifact
Some Research on the Lift and Stability of Wing-Body Combinations
The present paper summarizes and correlates broadly some of the research results applicable to fin-stabilized ammunition. The discussion and correlation are intended to be comprehensive, rather than detailed, in order to show general trends over the Mach number range up to 7.0. Some discussion of wings, bodies, and wing-body interference is presented, and a list of 179 papers containing further information is included. The present paper is intended to serve more as a bibliography and source of reference material than as a direct source of design information
Can Galactic Cosmic Rays Account for Solar 6Li Without Overproducing Gamma Rays?
Cosmic-ray interactions with interstellar gas produces both 6Li, which
accumulates in the interstellar medium (ISM), and mesons, which decay
to gamma-rays which propagate throughout the cosmos. Local 6Li abundances and
extragalactic gamma-rays thus have a common origin which tightly links them. We
exploit this connection to use gamma-ray observations to infer the contribution
to 6Li nucleosynthesis by standard Galactic cosmic-ray (GCR) interactions with
the ISM. Our calculation uses a carefully propagated cosmic-ray spectrum and
accounts for 6Li production from both fusion reactions () as well as from spallation channels ({p,\alpha+CNO \to ^6Li). We find
that although extreme assumptions yield a consistent picture, more realistic
ones indicate that solar 6Li cannot be produced by standard GCRs alone without
overproducing the hadronic gamma rays. Implications for the primordial 6Li
production by decaying dark matter and cosmic rays from cosmological structure
formation are discussed. Upcoming gamma-ray observations by GLAST will be
crucial for determining the resolution of this problem.Comment: 4 pages, 1 figure To be published in ApJ
Design methodology for a community response questionnaire on sonic boom exposure
A preliminary draft questionnaire concerning community response to sonic booms was developed. Interviews were conducted in two communities that had experienced supersonic overflights of the SR-71 airplane for several years. Even though the overflights had ceased about 6 months prior to the interviews, people clearly remembered hearing sonic booms. A total of 22 people living in central Utah and 23 people living along Idaho/Washington state border took part in these interviews. The draft questionnaire was constantly modified during the study in order to evaluate different versions. Questions were developed which related to annoyance, startle, sleep disturbance, building vibration, and building damage. Based on the data collected, a proposed community response survey response instrument was developed for application in a full-scale sonic boom study
The Revival of Galactic Cosmic Ray Nucleosynthesis?
Because of the roughly linear correlation between Be/H and Fe/H in low
metallicity halo stars, it has been argued that a ``primary'' component in the
nucleosynthesis of Be must be present in addition to the ``secondary''
component from standard Galactic cosmic ray nucleosynthesis. In this paper we
critically re-evaluate the evidence for the primary versus secondary character
of Li, Be, and B evolution, analyzing both in the observations and in Galactic
chemical evolution models. While it appears that [Be/H] versus [Fe/H] has a
logarithmic slope near 1, it is rather the Be-O trend that directly arises from
the physics of spallation production. Using new abundances for oxygen in halo
stars based on UV OH lines, we find that the Be-O slope has a large uncertainty
due to systematic effects, rendering it difficult to distinguish from the data
between the secondary slope of 2 and the primary slope of 1. The possible
difference between the Be-Fe and Be-O slopes is a consequence of the variation
in O/Fe versus Fe: recent data suggests a negative slope rather than zero
(i.e., Fe O) as is often assumed. In addition to a phenomenological
analysis of Be and B evolution, we have also examined the predicted LiBeB, O,
and Fe trends in Galactic chemical evolution models which include outflow.
Based on our results, it is possible that a good fit to the LiBeB evolution
requires only traditional the Galactic cosmic ray spallation, and the (primary)
neutrino-process contribution to B11. We thus suggest that these two processes
might be sufficient to explain Li6, Be, and B evolution in the Galaxy, without
the need for an additional primary source of Be and B.Comment: 25 pages, latex, 8 ps figures, figure 1 correcte
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