https://elib.bsu.by:443/handle/123456789/90803 NPCS Vol.16, no.1, pp. 1-104 (2013) 2026-04-20T08:11:17Z https://elib.bsu.by:443/handle/123456789/94306 Заглавие документа: Description of the Accelerated Universe Expansion without Dark Energy Авторы: Tomilchik, L. M. Аннотация: Based on the conformally invariant kinematical approach in combination with equivalence principle, it is shown that the observable dark energy effect can be interpreted as a manifestation of the remote observer‘s reference-system noninertiality. 2013-01-01T00:00:00Z https://elib.bsu.by:443/handle/123456789/94305 Заглавие документа: Polarized Bjorken Sum Rule Analysis: Revised Авторы: Khandramai, V. L.; Solovtsova, O. P.; Teryaev, O. V. Аннотация: We present progress in the QCD analysis of the Bjorken sum rule at low momentum transfers. We study asymptotic structure of the perturbative QCD expansion at low Q2 scales based on analysis of recent accurate data on the Bjorken sum rule and available now four-loop expression for the coefficient-function CBj(Q2). We demonstrate that the standard perturbative series for CBj(Q2) gives a hint to its asymptotic nature manifesting itself in the region Q2. 1 GeV2. It is confirmed by the considered integral model for the perturbative QCD correction. We extract a value of higher-twist µ4coefficient and study the interplay between higher orders and higher-twist contributions. Results of other approaches to the description of Bjorken sum rule data are discussed. 2013-01-01T00:00:00Z https://elib.bsu.by:443/handle/123456789/94285 Заглавие документа: Complete-Return Spectrum for a Generalized Rosen–Zener Two-State Term-Crossing Model Авторы: Shahverdyan, T. A.; Mogilevtsev, D. S.; Ishkhanyan, A. M.; Red’kov, V. M. Аннотация: The general semiclassical time-dependent two-state problem is considered for a specific field configuration referred to as the generalized Rosen–Zener model. This is a rich family of pulse amplitude- and phase-modulation functions describing both non-crossing and term-crossing models with one or two crossing points. The model includes the original constant-detuning non-crossing Rosen–Zener model as a particular case. We show that the governing system of equations is reduced to a confluent Heun equation. When inspecting the conditions for returning the system to the initial state at the end of the interaction with the field, we reformulate the problem as an eigenvalue problem for the peak Rabi frequency and apply the Rayleigh–Schrödinger perturbation theory. Further, we develop a generalized approach for finding the higher-order approximations, which is applicable for the whole variation region of the involved input parameters of the system. We examine the general surface U0n = U0n(δ0,δ1), n = const, in the three-dimensional space of input parameters, which defines the position of the n-th order return-resonance, and show that for fixed δ0the curve in {U0n,δ1} plane, i.e., the δ0= const section of the general surface is accurately approximated by an ellipse which crosses the U0n-axis at the points ±n and δ1-axis at the points δ11and δ12. We find a highly accurate analytic description of the functions δ11(δ0,n) and δ12(δ0,n) as the zeros of a Kummer confluent hypergeometric function. From the point of view of the generality, the analytical description of mentioned curve for the whole variation range of all involved parameters is the main result of the present paper. 2013-01-01T00:00:00Z https://elib.bsu.by:443/handle/123456789/94269 Заглавие документа: New Photocrosslinking Polymeric Materials for Liquid Crystal Photoalignment Авторы: Mahilny, Uladzimir; Trofimova, Alexandra; Stankevich, Alexander; Tolstik, Alexei; Murauski, Anatoli; Muravsky, Alexander Аннотация: The photoinduced alignment (photoalignment) of nematic liquid crystals (LC) is of great interest as a contactless technique to create patterned LC aligning layers which have good prospect as basic elements of nonlinear optical devices like controllable waveguide structures with discrete diffraction, statical and dynamical photonic media etc. LC photoalignment on the surface of benzaldehyde polymeric layer caused by photochemical reaction of benzaldehyde side groups is investigated experimentally and by numerical simulations. Arguments are offered to consider the photoalignment as based on formation of photocrosslinks involving anisotropic conjugated molecular structures. 2013-01-01T00:00:00Z