На основе результатов социологического исследования «Политические и гражданские установки студенчества Костромской области», проведенного среди студентов трех костромских вузов зимой 2015 г., проанализированы осо-бенности восприятия... more
На основе результатов социологического исследования «Политические и гражданские установки студенчества Костромской области», проведенного среди студентов трех костромских вузов зимой 2015 г., проанализированы осо-бенности восприятия провинциальными студентами такого социально-политического явления, как экстремизм. Ав-тор анализирует данное явление как в глобальном, так и в конкретно-страновом разрезе в проекции на современную Россию. В глобальном контексте автор указывает на тот факт, что в современном мире происходит эскалация мо-лодежного экстремизма. Это проявляется не только в идеологических установках молодых людей, но и в их действиях, повседневных практиках, образе жизни. Также показано, что в конкретно-страновом смысле феномен экстремизации определенной части молодежи тесно связан с внешнеполитическими событиями, которые оказывают как непосред-ственное, так и опосредованное влияние на Российскую Федерацию. Ключевые слова: молодежный экстремизм, молодежная политика, провинциальное студенчество. On the basis of results of sociological research " Political and civil installations of students of the Kostroma region " among students of three Kostroma high schools in the winter of the year of 2015, analyzed are features of perception by provincial students of such socio-political phenomenon as extremism. The author analyzes the named phenomenon in both global and country concrete contexts in projec on on modern Russia. As to global context, the author points to the fact, that modern world is being characterized by escala on of youth extremism. This is evident not only in ideological regula ons of young people, but also in their ac ons, everyday prac ces, and way of life. Also shown is, that as to country concrete meaning the phenomenon of extremaliza on of certain part of the youth is being closely connected with events of foreign policy, which exert both direct and indirect infl uence upon the Russian Federa on.
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We compute the one-loop scalar massless pentagon integral I_5^{6-2 eps} in D=6-2\eps dimensions in the limit of multi-Regge kinematics. This integral first contributes to the parity-odd part of the one-loop N=4 five-point MHV amplitude... more
We compute the one-loop scalar massless pentagon integral I_5^{6-2 eps} in D=6-2\eps dimensions in the limit of multi-Regge kinematics. This integral first contributes to the parity-odd part of the one-loop N=4 five-point MHV amplitude m_5^{(1)} at O(eps). In the high energy limit defined, the pentagon integral reduces to double sums or equivalently two-fold Mellin-Barnes integrals. By determining the O(eps) contribution to I_5^{6-2 eps}, one therefore gains knowledge of m_5^{(1)} through to O(eps^2) which is necessary for studies of the iterative structure of N=4 SYM amplitudes beyond one-loop. One immediate application is the extraction of the one-loop gluon-production vertex through to O(eps^2) and the iterative construction of the two-loop gluon-production vertex through to finite terms which is described in a companion paper. The analytic methods we have used for evaluating the pentagon integral in the high energy limit may also be applied to the hexagon integral and may ultimately give information on the form of the remainder function.
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For Abstract see ChemInform Abstract in Full Text.
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ABSTRACT For Abstract see ChemInform Abstract in Full Text.
Applying asymptotic expansions at threshold, we compute the two-loop quantum chromodynamics (QCD) correction to the short-distance coefficient that governs the leptonic decay ψ-->l+l- of an S-wave quarkonium state and discuss its impact... more
Applying asymptotic expansions at threshold, we compute the two-loop quantum chromodynamics (QCD) correction to the short-distance coefficient that governs the leptonic decay ψ-->l+l- of an S-wave quarkonium state and discuss its impact on the relation between the quarkonium nonrelativistic wave function at the origin and the quarkonium decay constant in full QCD.
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The angular dependence of light-trapping in nanophotonic thin-film solar cells is inherent due to the wavelength-scale dimensions of the periodic nanopatterns. In this paper, we experimentally investigate the dependence of light coupling... more
The angular dependence of light-trapping in nanophotonic thin-film solar cells is inherent due to the wavelength-scale dimensions of the periodic nanopatterns. In this paper, we experimentally investigate the dependence of light coupling to waveguide modes for light trapping in a-Si:H solar cells deposited on nanopatterned back contacts. First, we accurately determine the spectral positions of individual waveguide modes in thin-film solar cells in external quantum efficiency and absorptance. Second, we demonstrate the strong angular dependence of this spectral position for our solar cells. Third, a moderate level of disorder is introduced to the initially periodic nanopattern of the back contacts. As a result, the angular dependence is reduced. Last, we experimentally compare this dependence on the angle of incidence for randomly textured, 2D periodically nanopatterned and 2D disordered back contacts in external quantum efficiency and short-circuit current density.
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In the planar N=4 supersymmetric Yang-Mills theory, the conformal symmetry constrains multi-loop n-edged Wilson loops to be basically given in terms of the one-loop n-edged Wilson loop, augmented, for n greater than 6, by a function of... more
In the planar N=4 supersymmetric Yang-Mills theory, the conformal symmetry constrains multi-loop n-edged Wilson loops to be basically given in terms of the one-loop n-edged Wilson loop, augmented, for n greater than 6, by a function of conformally invariant cross ratios. We identify a class of kinematics for which the Wilson loop exhibits exact Regge factorisation and which leave invariant the analytic form of the multi-loop n-edged Wilson loop. In those kinematics, the analytic result for the Wilson loop is the same as in general kinematics, although the computation is remarkably simplified with respect to general kinematics. Using the simplest of those kinematics, we have performed the first analytic computation of the two-loop six-edged Wilson loop in general kinematics.
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The singular chain complex of the iterated loop space is expressed in terms of the cobar construction. After that we consider the spectral sequence of the cobar construction and calculate its first term over Z/p-coefficients and over a... more
The singular chain complex of the iterated loop space is expressed in terms of the cobar construction. After that we consider the spectral sequence of the cobar construction and calculate its first term over Z/p-coefficients and over a field of characteristic zero. Finally we apply these results to calculate the homology of the iterated loop spaces of the stunted real and complex projective spaces. In the Appendix, written by F.Sergeraert there are considered computer methods for calculations of the homology of iterated loop spaces.
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ABSTRACT Modern construction industry is in need of new building materials with improved operational properties. One of such materials is the sulfur-bituminous concrete – composite with matrix formed from sulfur and bitumen mix. Despite... more
ABSTRACT Modern construction industry is in need of new building materials with improved operational properties. One of such materials is the sulfur-bituminous concrete – composite with matrix formed from sulfur and bitumen mix. Despite the high values of operational properties and economic efficiency of such concrete, there is the lack of necessary knowledge about technological properties of sulfur-bituminous concrete mix. The results of numerical modeling can be used to make initial decisions concerning values of control variables (relevant to mixture and technology). In the given work we present short review of the model and simulation algorithm involving particle systems as a material's model and discuss the modeling results obtained during numerical studies of compaction process of sulfur-bitumen concrete. It is shown that for aggregates with size of one centimeter the optimal value of average thickness of the sulfur-bitumen layer is near to the one millimeter. Concrete mixes for which this condition is met can be characterized by dense structure similar to face-centered cubic.
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We evaluate, exactly in d, the master integrals contributing to massless threeloop QCD form factors. The calculation is based on a combination of a method recently suggested by one of the authors (R.L.) with other techniques: sector... more
We evaluate, exactly in d, the master integrals contributing to massless threeloop QCD form factors. The calculation is based on a combination of a method recently suggested by one of the authors (R.L.) with other techniques: sector decomposition implemented in <Literal>FIESTA</Literal>, the method of Mellin-Barnes representation, and the PSLQ algorithm. Using our results for the master integrals we obtain analytical expressions for two missing constants in the γ-expansion of the two most complicated master integrals and present the form factors in a completely analytic form.
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Explicit formulae for asymptotic expansions of Feynman diagrams in typical limits of momenta and masses with external legs on the mass shell are presented.
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ABSTRACT Amorphous silicon (a-Si:H) solar cells in p-i-n configuration were developed at a low deposition temperature of 140 °C, suitable for application on transparent flexible plastic substrates. Deteriorated electronic properties of... more
ABSTRACT Amorphous silicon (a-Si:H) solar cells in p-i-n configuration were developed at a low deposition temperature of 140 °C, suitable for application on transparent flexible plastic substrates. Deteriorated electronic properties of the p-layer with decreasing temperature were identified as the main reason for reduced solar cell performance. Optimization of the p-layer properties resulted in an efficiency of 8.2 % for a solar cell fabricated entirely at 140 °C. As a parallel application scenario, a-Si:H/a-Si:H tandem solar cells are designed for application in integrated photoelectrochemical water splitting modules. Here we benefit from the increased open circuit voltages with values around 1.9 V which provides ample margin for possible overpotential losses in water splitting modules.
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General prescriptions of differential renormalization are presented. It is shown that renormalization group functions are straightforwardly expressed through some constants that naturally arise within this approach. The status of the... more
General prescriptions of differential renormalization are presented. It is shown that renormalization group functions are straightforwardly expressed through some constants that naturally arise within this approach. The status of the action principle in the framework of differential renormalization is discussed.
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This paper makes a study of operads and of coalgebras over operads. Certain operads En and E are defined, constituting the algebraic analogues of the "little n-cube" operads; it is then shown that the singular chain complex C*(X;R) of a... more
This paper makes a study of operads and of coalgebras over operads. Certain operads En and E are defined, constituting the algebraic analogues of the "little n-cube" operads; it is then shown that the singular chain complex C*(X;R) of a topological space X is a coalgebra over the operad E, and that this structure completely determines the weak homotopy type of the space. Bibliography: 26 titles.
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Whereas at development of the meteor phenomenon there are processes in different temporary scales (more slow processes heat conductivity, mechanical rotation, destruction) and considerably faster (fluctuations of brightness of radiating... more
Whereas at development of the meteor phenomenon there are processes in different temporary scales (more slow processes heat conductivity, mechanical rotation, destruction) and considerably faster (fluctuations of brightness of radiating plasma is like gas-dynamical laser), the observable flares of meteors differ as on to nature, and on appearance caused by character of radiation. Let's name "mechanical" flares - as a type A, "laser" - type B. On Fig.2 in work [1] is shown type A, on Fig.1 in [1] is shown type B for rather slow fireballs, when laser processes " not have time " to be shown as change of brightness of radiation. In work [2] on Fig 1 is shown spectrum of Leonid fireball, in which imposing both types of flares most likely is shown. References 1. Smirnov V.A. Peculiarities of meteor radiation, Advaces in Space Research 39, number 4, 526 - 532, 2007 2. Shinsuke Abe, Noboru Ebizuka, Hajime Yano, Jun-ichi Watanabe, Jiri Borovicka. Search for OH (A - X) and detection of N2 + (B - X) in ultraviolet mateor spectrum, Advances in Space Research 39, 4, 538 - 543, 2007.
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Recent results on the analytical evaluation of double-box Feynman integrals and the corresponding methods of evaluation are briefly reviewed.
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We sum up the next-to-leading logarithmic corrections to the heavy-quarkonium hyperfine splitting, using the nonrelativistic renormalization group. On the basis of this result, we predict the mass of the etab meson to be... more
We sum up the next-to-leading logarithmic corrections to the heavy-quarkonium hyperfine splitting, using the nonrelativistic renormalization group. On the basis of this result, we predict the mass of the etab meson to be M(etab)=9421±11(th)+9-8(deltaalphas) MeV. The experimental measurement of M(etab) with a few MeV error would be sufficient to determine alphas(MZ) with an accuracy of ±0.003. For the hyperfine splitting
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We analyze the large-order behaviour in perturbation theory of classes of diagrams with an arbitrary number of chains (i.e. photon lines, dressed by vacuum polarization insertions). We derive explicit formulae for the leading and... more
We analyze the large-order behaviour in perturbation theory of classes of diagrams with an arbitrary number of chains (i.e. photon lines, dressed by vacuum polarization insertions). We derive explicit formulae for the leading and subleading divergence as n, the order in perturbation theory, tends to infinity, and a complete result for the vacuum polarization at the next-to-leading order in an expansion in l / N f, where N f is the number of fermion species. In general, diagrams with more chains yield stronger divergence. We define an analogue of the familiar diagrammatic R-operation, which extracts ultraviolet renormalon counterterms as insertions of higher-dimension operators. We then use renormalization group equations to sum the leading (in n/ N f ) k corrections to all orders in l INf and find the asymptotic behaviour in n up to a constant that must be calculated explicitly order by order in 1/ Nf.
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We present a historical review of the problem of obtaining the meteor plasma radiation coefficient. Meteor spectrophotometry endures to fail in determining spectral line profiles, because an existing spectrograph has to give a monochrome... more
We present a historical review of the problem of obtaining the meteor plasma radiation coefficient. Meteor spectrophotometry endures to fail in determining spectral line profiles, because an existing spectrograph has to give a monochrome image of the meteors instead of a spectral line. Therefore, it is rather difficult to take the self-absorption magnitude as affecting the decrease of radiation intensity into account. Numerical calculation for the radiation coefficient are given, based on data of absolute spectrophotometry of meteors (Smirnov 1994). The accuracy in determining the coefficient of meteor plasma radiation thus depends on the procedure of averaging different parameters which characterize the radiation. The correction factor of 10^-3 to 10^-4 can be used to estimate the meteoroid matter influx to the Earth. It is proposed to determine refined spectral radiation coefficients from spectrograms obtained from artificial disintegrating cosmic objects with known chemical composition and initial mass. The space station Mir could be used as such an object.
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We present an expression for the leading-color (planar) four-loop four-point amplitude of N=4 supersymmetric Yang-Mills theory in 4-2γ dimensions, in terms of eight separate integrals. The expression is based on consistency of unitarity... more
We present an expression for the leading-color (planar) four-loop four-point amplitude of N=4 supersymmetric Yang-Mills theory in 4-2γ dimensions, in terms of eight separate integrals. The expression is based on consistency of unitarity cuts and infrared divergences. We expand the integrals around γ=0, and obtain analytic expressions for the poles from 1/γ8 through 1/γ4. We give numerical results for the coefficients of the 1/γ3 and 1/γ2 poles. These results all match the known exponentiated structure of the infrared divergences, at four separate kinematic points. The value of the 1/γ2 coefficient allows us to test a conjecture of Eden and Staudacher for the four-loop cusp (soft) anomalous dimension. We find that the conjecture is incorrect, although our numerical results suggest that a simple modification of the expression, flipping the sign of the term containing ζ32, may yield the correct answer. Our numerical value can be used, in a scheme proposed by Kotikov, Lipatov, and Velizhanin, to estimate the two constants in the strong-coupling expansion of the cusp anomalous dimension that are known from string theory. The estimate works to 2.6% and 5% accuracy, providing nontrivial evidence in support of the AdS/CFT correspondence. We also use the known constants in the strong-coupling expansion as additional input to provide approximations to the cusp anomalous dimension which should be accurate to under 1% for all values of the coupling. When the evaluations of the integrals are completed through the finite terms, it will be possible to test the iterative, exponentiated structure of the finite terms in the four-loop four-point amplitude, which was uncovered earlier at two and three loops.
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The general n-point massless p-adic Feynman amplitude with arbitrary parameters of analytic regularization for each line is calculated. This result is presented in the form of a sum over hierarchies of a given graph. The structure of... more
The general n-point massless p-adic Feynman amplitude with arbitrary parameters of analytic regularization for each line is calculated. This result is presented in the form of a sum over hierarchies of a given graph. The structure of ultraviolet and infrared divergences of p-adic Feynman amplitudes is characterized and the startriangle uniqueness identity in the p-adic case is derived.
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We extend the property-rights framework to allow for: a separation of the ownership rights of access and veto; and sequential investment. Parties investing first (ex ante) do so before contracting is possible. Parties that invest second... more
We extend the property-rights framework to allow for: a separation of the ownership rights of access and veto; and sequential investment. Parties investing first (ex ante) do so before contracting is possible. Parties that invest second (ex post) can contract on (at least some) of their investment costs. Along with this cost-sharing effect, the incentive to invest is affected by