2,996 research outputs found
Bell inequalities for random fields
The assumptions required for the derivation of Bell inequalities are not
usually satisfied for random fields in which there are any thermal or quantum
fluctuations, in contrast to the general satisfaction of the assumptions for
classical two point particle models. Classical random field models that
explicitly include the effects of quantum fluctuations on measurement are
possible for experiments that violate Bell inequalities.Comment: 18 pages; 1 figure; v4: Essentially the published version; extensive
improvements. v3: Better description of the relationship between classical
random fields and quantum fields; better description of random field models.
More extensive references. v2: Abstract and introduction clarifie
The galactic foreground angular spectra
Galactic synchrotron and free-free foregrounds angular spectra are
analytically estimated with account for interstellar turbulence and radiating
process physics. Unknown parameters of the spectra are obtained by fitting to
observational data
Short-Wave Excitations in Non-Local Gross-Pitaevskii Model
It is shown, that a non-local form of the Gross-Pitaevskii equation allows to
describe not only the long-wave excitations, but also the short-wave ones in
the systems with Bose-condensate. At given parameter values, the excitation
spectrum mimics the Landau spectrum of quasi-particle excitations in superfluid
Helium with roton minimum. The excitation wavelength, at which the roton
minimum exists, is close to the inter-particle interaction range. It is shown,
that the existence domain of the spectrum with a roton minimum is reduced, if
one accounts for an inter-particle attraction.Comment: 5 pages, 5 figures, UJP style; presented at Bogolyubov Kyiv
Conference "Modern Problems of Theoretical and Mathematical Physics",
September 15-18, 200
Nonlinear acoustic waves in channels with variable cross sections
The point symmetry group is studied for the generalized Webster-type equation
describing non-linear acoustic waves in lossy channels with variable cross
sections. It is shown that, for certain types of cross section profiles, the
admitted symmetry group is extended and the invariant solutions corresponding
to these profiles are obtained. Approximate analytic solutions to the
generalized Webster equation are derived for channels with smoothly varying
cross sections and arbitrary initial conditions.Comment: Revtex4, 10 pages, 2 figure. This is an enlarged contribution to
Acoustical Physics, 2012, v.58, No.3, p.269-276 with modest stylistic
corrections introduced mainly in the Introduction and References. Several
typos were also correcte
Attribution of observed changes in stratospheric ozone and temperature
Three recently-completed sets of simulations of multiple chemistry-climate models with greenhouse gases only, with all anthropogenic forcings, and with anthropogenic and natural forcings, allow the causes of observed stratospheric changes to be quantitatively assessed using detection and attribution techniques. The total column ozone response to halogenated ozone depleting substances and to natural forcings is detectable in observations, but the total column ozone response to greenhouse gas changes is not separately detectable. In the middle and upper stratosphere, simulated and observed SBUV/SAGE ozone changes are broadly consistent, and separate anthropogenic and natural responses are detectable in observations. The influence of ozone depleting substances and natural forcings can also be detected separately in observed lower stratospheric temperature, and the magnitudes of the simulated and observed responses to these forcings and to greenhouse gas changes are found to be consistent. In the mid and upper stratosphere the simulated natural and combined anthropogenic responses are detectable and consistent with observations, but the influences of greenhouse gases and ozone-depleting substances could not be separately detected in our analysis
Information system on microbial collections as a part of bioresource collections portal for Russia’s FASO organizations: a working protocol
Nowadays, many scientific organizations of Russia own collections of microorganisms on which large volumes of information have been generated. These data represent the descriptions of objects of diverse nature (bacteria, archaea, fungi, protists) and their properties, which have been carefully collected and cataloged by generations of researchers. Not every organization that has such collections has an open access electronic catalog, which not only complicates work with these unique materials, but also even hides the fact of the existence of such collections. This state of affairs requires the development of electronic resources for presenting these materials to the scientific community. To put together the information on microorganism collections, we have developed an internet portal (http://www.biores.cytogen.ru/microbes/) of microbial bioresource collections of FASO organizations in the Russian Federation. The portal was created under the project developing the information system for bioresource collections of FASO institutes. It is a platform where collection organizations can place information about the storage units of their collections, as well as other information on collections, including links to their own catalogs. In this paper, we describe the principles of working with the portal. The portal’s graphical interface allows users, both registered and unregistered, to receive the following information about collections of microorganisms: a list of collections represented in the database, contact details of the organization and information about the curator of the collection, summary statistics for each collection, as well as information on storage units. Registered users – owners of collections – have the opportunity to create and modify records about the storage units of their collections, and to update their description. To automate work with the portal, software access to the database through the REST API has been implemented (http://api.biores.cytogen.ru/ microbes/). At present, the portal is still being filled, but it already contains a description of more than 13,000 items of storage (of which 3500 are in the microorganisms’ part) of 65 bioresource collections in Russia’s FASO organizations. Of these collections, 12 with microorganisms have a total diversity of funds of about 50,000 strains)
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