90 research outputs found
Is Sustainable Development of Deserts Feasible?
No full textHot deserts that presently cover about one-fifth of the land area of our planet are rapidly devouring more and more arable lands mostly due to anthropogenic causes. We propose an interdisciplinary approach to revitalizing and commercializing hot deserts, which is based on systems thinking and Russian and NASA space technology experience in designing life-support systems for long-duration flights. We formulate ten principles for the design of sustainable life support systems in deserts, which can make the development of the deserts feasible. It is discussed how the principles can be employed to design and operate desert’s eco-industrial parks with greenhouses in which the transpired and evaporated moisture is collected and condensed. The potential benefits of setting up the eco-industrial parks in deserts include the slowdown and eventual reversal of the desertification trend, the migration of many industrial production facilities from mild-climate regions to deserts, the increased availability of potable water and food in deserts, the development of poor African countries, and the emergence of new investment markets
Polyakov-Mellin bootstrap for AdS loops
No full textWe consider holographic CFTs and study their large N expansion. We use Polyakov-Mellin bootstrap to extract the CFT data of all operators, including scalars, till O(1/N4). We add a contact term in Mellin space, which corresponds to an effective �4 theory in AdS and leads to anomalous dimensions for scalars at O(1/N2). Using this we fix O(1/N4) anomalous dimensions for double trace operators finding perfect agreement with 1 (for �� = 2). Our approach generalizes this to any dimensions and any value of conformal dimensions of external scalar field. In the second part of the paper, we compute the loop amplitude in AdS which corresponds to non-planar correlators of in CFT. More precisely, using CFT data at O(1/N4) we fix the AdS bubble diagram and the triangle diagram for the general case. © 2020, The Author(s)
Thermodynamics and phase diagrams of Polyakov-loop extended chiral models
No full textWe study the thermodynamics and phase diagrams of two-flavor quantum chromodynamics using the Polyakov-loop extended quark-meson (PQM) model and the Pisarski-Skokov chiral matrix (χM) model [1]. At temperatures up to T≈2Tc and baryon chemical potentials up to μB=400 MeV, both models show reasonable agreement with the pressure, energy density, and interaction measure as calculated on the lattice. The Polyakov loop is found to rise significantly faster with temperature in models than on the lattice. In the low-temperature and high baryon density regime, the two models predict different states of matter; The PQM model predicts a confined and chirally restored phase, while the χM model predicts a deconfined and chirally restored phase. At finite isospin density and zero baryon density, the onset of pion condensation at T=0 is at μI=12mπ, and the transition is second order at all temperatures. The transition temperature for pion condensation coincides with that of the chiral transition for values of the isospin chemical potential larger than approximately 110 MeV. In the χM model, they also coincide with the transition temperature for deconfinement. The results are in good overall agreement with recent lattice simulations of the μI–T phase diagram.publishedVersionPublished by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3
Analysis of Antarctic Ice Core Data (EPICA Dome C) with Flicker-Noise Spectroscopy
No full textEvolution of Earth’s climate system over the past 800,000 years represents a complex process with successions of uneven glacial and interglacial periods. The length, amplitudes, and development of each climate cycle depend on a number of different factors, including the orbital parameters attributed to insolation and the complex responses of the Earth system to solar radiation primarily through the amplification by Earth’s albedo and greenhouse gas and secondarily through a system of heat reservoirs, such as ice sheet and deep ocean, distributed throughout our planet. The purpose of this study is to analyze the transitions related to climate cycles in Antarctic ice core data (EPICA Dome C) of deuterium composition and dust concentration recorded for the past 800,000 years [1] using Flicker-Noise Spectroscopy (FNS), an analytical toolset for the extraction and analysis of information in stochastic time and space series, containing both regular and chaotic components, by using power spectra and difference moments (structural functions) of various orders [2]. 

The FNS nonstationarity factors for the deuterium composition and dust (logarithm) concentration, which represent the normalized discrete derivative of the second-order structural function of the source signal with respect to a given shifted “window” interval, were built for different intervals of averaging to identify the major changes in the dynamics of both time series and their precursors. It is shown that when displayed together with the source signals, the positive peaks in the nonstationarity factors provide more reliable estimates of the transition of the climate system from one sub-period to another within a specific climate cycle as compared to predefined thresholds in dust or deuterium values. For climatic transitions, the power spectral estimates of the nonstationarity factors contain several periodicities in addition to the orbital ones. These frequencies may be attributed to specific heat accumulation and discharge processes in the climate system. The results of this study demonstrate the potential of FNS in the analysis of climate data series and may be used in refining climate transition models.

This study was supported by the Russian Foundation for Basic Research, project no. 08-02-00230a.
[1] Lambert F., et al. (2008) Dust-climate couplings over the past 800,000 years from the EPICA Dome C ice core, Nature 452, 616-619.
[2] Timashev, S. F., Polyakov Yu. S. (2007) Review of flicker noise spectroscopy in electrochemistry, Fluctuations and Noise Letters 7(2), R15-R47.

Feedback algorithm for switch location : analysis of complexity and application to network design
No full textAn accelerated feedback algorithm to solve the single-facility minisum problem is studied with application to designing networks with the star topology. The algorithm, in which the acceleration with respect to the Weiszfeld procedure is achieved by multiplying the current Weiszfeld iterate by an accelerating feedback factor, is shown to converge faster than the accelerating procedures available in the literature. Singularities encountered in the algorithm are discussed in detail. A simple practical exception handling subroutine is developed. Several applications of the algorithm to designing computer networks with the star topology are demonstrated. Applications of the algorithm as a subroutine for multi-switch location problems are considered. Various engineering aspects involved in acquiring and processing coordinates for geographic locations are discussed. A complete algorithm in pseudocode along with the source code listing in Mathematica 4.1 is presented
General theory of law in the integrate context: the continuation of the dialogue (devoted to the second edition of the manual A. V. Polyakov “General theory of law: problems of interpretation in the context of the communicative approach”)
No full textOn the one hand, the author appreciates the integrate and communicative approaches, developed by
A. V. Poyakov. On the other hand, the author considers it necessary to continue the dialogue about
these approaches with a view to their improvement, as well as the dialogue on the problems and the
prospects of the Russian theory of law in the light of these approaches. The reason for the article was
the release of the second edition of the textbook of A. V. Polyakov “General theory of law. A course
of lectures”. It is examined the relevance of this edition. This relevance is due to persistence in the
general theory of law of dominant positions of statism, positivism, as well as the theory of natural law.
Both that, and another, and the third significantly limits the legal communication, makes it imperfect.
The author examines the philosophical and methodological novelty, as well as the advantages of the
A. V. Polyakov`s tutorial in light of accents made the new edition. Chief among those accents is the
concept of a full-featured legal communication. It is explored the question, why the communicative
theory of law among Russian scientists caused and continues to cause negative assessments and sharp
criticism. The reasons for such assessments include a one-sided attention to “postclassical” provisions
and ignoring the neoclassical provisions that complement the latter in the works of A. V. Polyakov. The
article contains suggestions for improving the integrate and communicative approaches. The most
appropriate form of implementation of these suggestions, is an updated version of the system presentation
of communicative theory of law in the form of a textbook or monograph. Refs 28
Mesonic excitations and pi-pi scattering lengths at finite temperature in the two-flavor Polyakov-Nambu-Jona-Lasinio model
No full textThe mesonic excitations and s-wave pi-pi scattering lengths at finite temperature are studied in the two-flavor Polyakov-Nambu-Jona-Lasinio (PNJL) model. The masses of the pi and sigma mesons, pion-decay constant, the pion-quark coupling strength, and the scattering lengths a(0) and a(2) at finite temperature are calculated in the PNJL model with two forms of Polyakov-loop effective potential. The obtained results are almost independent of the choice of the effective potentials. The calculated results in the PNJL model are also compared with those in the conventional Nambu-Jona-Lasinio model and indicate that the effect of color confinement screens the effect of temperature below the critical one in the PNJL model. Furthermore, the Goldberger-Treiman relation and the Gell-Mann-Oakes-Renner relation are extended to the case at finite temperature in the PNJL model.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000266408300038&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Astronomy & AstrophysicsPhysics, Particles & FieldsSCI(E)15ARTICLE7null7
Phase diagrams in the hadron-Polyakov-Nambu-Jona-Lasinio model
No full textThe two-equation of state model is used to describe the hadron-quark phase transition in dense-hot matter formed in heavy-ion collisions. The nonlinear Walecka model is used to describe the hadronic phase. For the quark phase, the Nambu-Jona-Lasinio (NJL) model coupled to Polyakov-loop fields is used to include both the chiral and (de) confinement dynamics. The phase diagrams are derived from the Gibbs conditions and compared with the results obtained in the hadron-NJL model without confinement. As in the hadron-NJL case a first order transition is observed, but with a critical end point at much higher temperatures, a consequence of the confinement mechanism that reduces the degrees of freedom of the quark matter in proximity to the phase transition. Particular attention is devoted to the phase transition in isospin asymmetric matter. Interesting isospin effects are found at high baryon density and reduced temperatures, which are in fact also common to other quark models, like the MIT bag model and the NJL model. Some possible observational signals are suggested to probe in heavy-ion collision experiments at intermediate energies.Astronomy & AstrophysicsPhysics, Particles & FieldsSCI(E)10ARTICLE3null8
Stochastic wave-function simulation of irreversible emission processes for open quantum systems in a non-Markovian environment
No full textScalar soliton quantization with generic moduli
No full textThis article is distributed under the terms of the Creative Commons
Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in
any medium, provided the original author(s) and source are credArticle funded by SCOAP3. CP is
a Royal Society Research Fellow and partly supported by the U.S. Department of Energy
under grants DOE-SC0010008, DOE-ARRA-SC0003883 and DOE-DE-SC0007897. ABR
is supported by the Mitchell Family Foundation. We would like to thank the Mitchell
Institute at Texas A&M and the NHETC at Rutgers University respectively for hospitality
during the course of this work. We would also like to acknowledge the Aspen Center
for Physics and NSF grant 1066293 for a stimulating research environment which led to
questions addressed in this paper
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