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Документ The Shape of Multidimensional Gravity: Non-relativistic Limit(Astroprint, 2009) Zhuk, Alexander; Eingorn, MaximIt is found the exact solution of the Poisson equation for the multidimensional space with topology M3+d = R3 ×Td. This solution describes smooth transition from the Newtonian behavior 1/r3 for distances bigger than periods of tori (the extra dimension sizes) to multidimensional behavior 1/r1+d 3+d in opposite limit. In the case of one extra dimension d = 1, the gravitational potential is expressed via compact and elegant formula. Obtained formula is applied to an infinitesimally thin shell, a shell, a sphere and two spheres to show deviations from the Newtonian expressions. It is shown that the corrections to the gravitational constant in the Cavendish-type experiment can be within the measurement accuracy of Newton’s gravitational constant GN. It is proposed models where the test masses are smeared over some (or all) extra dimensions. In 10-dimensional spacetime with 3 smeared extra dimensions, it is shown that the size of 3 rest extra dimensions can be enlarged up to submillimeter for the case of 1TeV fundamental Planck scale MPl(10). In the models where all extra dimensions are smeared, the gravitational potential exactly coincides with the Newtonian one. Nevertheless, the hierarchy problem can be solved in these models.Документ The catalog of periods of the variability of blazars 3C120, 3C273, 3C279, 3C345 and 3C454.3 at centimeter and millimeter wavelengths(Odessa I.I. Mechnikov National University, 2009) Volvach, A. E.; Ryabov, Myhaylo I. ; Volvach, L. N.; Sukharev, Artem L.; Aller, H. D.; Aller, M. F.; Рябов, Михайло ІвановичccVariations in the radio flux of 3C120, 3C273, 3C279, 3C345, 3C 454.3 are analyzed using long-term monitoring data at five frequencies from 4.8 to 36.8 GHz obtained at the University ofMichigan Radio Astronomy Observatory and the Crimean Astrophysical Observatory. A spectral analysis of the light curves at the various frequencies reveals the presence of periodic components. Using method of model calculations for each of the found period tested its ability to reproduce the observed flux variability at different frequencies. On the basis of the model calculations presented the catalog of the most reliable periods of flux variable of radio sources.Документ The 6th Gamow Summer School: Astronomy and Beyond: Astrophysics, Cosmology, Radioastronomy, Astrobiology(2007) Ryabov, Myhaylo I. ; Рябов, Михайло Іванович; Madrid : Consejo Superior de Investigaciones Científicas, Instituto Miguel Asín,Документ Flux density evolution of the sources 3C273, 3C279 and 3C454.3 at the frequencies 102 MHz–36.8 GHz(2007) Volvach, A. E.; Volvach, L. N.; Larionov, M. G.; Aller, H. D.; Aller, M. F.; Yurovskiy, Yu. Yu.; Ryabov, Myhaylo I. ; Рябов, Михайло Іванович; Madrid : Consejo Superior de Investigaciones Científicas, Instituto Miguel Asín,The results of long-term monitoring of the sources 3C273, 3C279 and 3C454.3 at 102 MHz–36.8 GHz are presented. Numerical analysis of irregular temporal rows of the integral fluxes allowed us to detect the quasiperiodic constituents of the emission flux variations. The analysis of the parameters of binary black holes in the central regions of non-stationary objects demonstrates that these super-massive objects have an insignificant variation between the sizes of the orbits of partners, and that they are in the stage of evolution different from the time of merging by a period of less than 104 years.Документ Effective Friedmann model from multidimensional cosmologies(2007) Zhuk, AlexanderWe investigate the possibility of the construction of the conventional Friedmann cosmology for our observable Universe if the underlying theory is the multidimensional Kaluza–Klein model.We show that the effective Friedmann model obtained by dynamic compactification of the multidimensional model is faced with too strong variations in the fundamental constants. On the other hand, models with stable compactification of the internal space are free from this problem and also result in conventional four-dimensonal cosmological behaviour for our Universe. We prove a no-go theorem, which shows that stable compactification of the internal spaces is possible only if the equations of state in the external and internal spaces are properly adjusted to each other. With a proper choice of parameters (fine tuning), the effective cosmological constant in this model provides the late-time acceleration of the Universe.Документ Sp-branes: integrable multidimensional cosmologies(2007) Baukh, V.; Zhuk, Alexander; Madrid : Consejo Superior de Investigaciones Científicas, Instituto Miguel Asín,We investigate time-dependent solutions (Sp-brane solutions) for product manifolds consisting of factor spaces where only one of them is of a non-Ricci-flat type. Our model contains a minimally coupled free scalar field and form field (flux) as matter sources.We discuss the possibility of generating late-time acceleration of the Universe. For these models, we investigate the variation with time of the effective four-dimensional fundamental ‘constants’. We show that experimental bounds for the fundamental constant variations apply strong restrictions to the considered models.Документ A nonlinear multidimensional gravitational model R+R-1 with form fields and stabilized extra dimensions(Madrid : Consejo Superior de Investigaciones Científicas, Instituto Miguel Asín,, 2007) Saidov, T.; Zhuk, AlexanderWe studied multidimensional gravitational models with scalar curvature nonlinearity of the type R−1 and with form fields (fluxes) as a matter source. It is assumed that the higher-dimensional space–time undergoes Freund–Rubin-like spontaneous compactification to a warped product manifold. It is shown that for certain parameter regions the model allows for freezing stabilization of the internal space near the positive minimum of the effective potential, which plays the role of the positive effective cosmological constant. However, the parameters of model should be fine tuned to obtain the observable dark energy.Документ Abundances of neutron-capture elements in red giant stars(Madrid : Consejo Superior de Investigaciones Científicas, Instituto Miguel Asín,, 2007) Gorbaneva, Tatyana I.The neutron-capture element abundances in the 52 red giants with metallicities spanning the range −0.6 < [Fe]/[H] < 0.25 are found. High-resolution spectra (R = 42000; S/N > 100) for the investigated stars were obtained with the ELODIE spectrograph of the 1.93m telescope at the Observatoire de Haute Provence (France). The determination of elemental abundances was carried out with the local thermodynamic equilibrium assumption by the model atmosphere method; for Ba and Eu the hyperfine structure was taken into account. The dependences of the neutron-capture element abundances on metallicity are presented.Документ Homogeneous three-dimentional spaces and cosmological models(Odessa I.I. Mechnikov National University, 2009) Olyeynik, Vyacheslav P.; Chopyk, S.Документ Improved mathematical modeling of the angular size of the Roche lobe(Odessa I.I. Mechnikov National University, 2009) Andronov, Ivan L.; Breus, Vitalii V.Документ Mathematical modeling of the photometric variability of three newly discovered variable stars(Odessa I.I. Mechnikov National University, 2009) Andronov, Ivan L.; Virnina, Natalia A.Документ V473 Lyra: spectroscopic determinations of effective tempratures and absolute stellar magnitudes in various phases(Astroprint, 2009) Chekhonadskikh, FedorДокумент A catalogue of galaxy clusters and groups as base for new galaxy supercluster catalogue(Odessa I.I. Mechnikov National University, 2009) Panko, Olena O.; Панько, Олена Олексіївна; Панько, Елена АлексеевнаДокумент The main properties of flux variability of extragalactic radio sources bl lac and oj287(Odessa I.I. Mechnikov National University, 2009) Ryabov, Myhaylo I. ; Sukharev, Artem L.; Рябов, Михайло ІвановичДокумент Dynamics and evolution complexes of activity on the sun on various phases of 23 cycle(Odessa I.I. Mechnikov National University, 2009) Ryabov, Myhaylo I. ; Lukashuk, S. A.; Рябов, Михайло ІвановичДокумент Ionosphere response to solar eclipse effect on magnetosphere(Odessa I.I. Mechnikov National University, 2009) Derevyagin, V. G.; Lytvynenko, I. O.; Lytvynenko, O. A.Документ Atmosphere drag properties of satellite under influence of "space weather"(Odessa I.I. Mechnikov National University, 2009) Koshkin, Nikolay I.; Korobeynikova, E. A.; Ryabov, Myhaylo I. ; Strakhova, Svitlana I.; Sukharev, Artem L.; Кошкин, Николай Иванович; Кошкін, Микола Іванович; Рябов, Михайло ІвановичДокумент Simple radio telescopes of low frequences(Odessa I.I. Mechnikov National University, 2009) Lytvynenko, I. O.; Lytvynenko, O. A.; Koshukhar, V. B.Документ Взаимодействие фотовозбужденных j-агрегатов красителя адсорбированных на поверхности микрокристаллов галогенидов серебра(2010) Тюрин, Александр Валентинович; Жуков, Сергей Александрович; Берков, Юрий Николаевич; Зеленин, П. В.; Тюрін, Олександр Валентинович; Жуков, Сергій Олександрович; Берков, Юрій Миколайович; Зеленін, П. В.; Tyurin, Oleksandr V.; Zhukov, Serhii O.; Berkov, Yurii M.; Zelenin, P. V.Документ High-power monochromatic gamma radiation sources on the basis of meta-stable nuclei discharge induced by muon capture and nuclear sensors(Астропринт, 2010) Glushkov, A. V.; Lepikh, Yaroslav I.; Лепих, Ярослав Ильич; Лепіх, Ярослав Ілліч