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1.
Dynamical and kinematic properties of Bianchi-II cosmological models with rotation and expansion are investigated. Exact solutions of Einstein field equations are obtained which describe the evolution of a rotating Universe. Exact solutions of null, timelike and spacelike geodesics are constructed. Two new cosmological tests for rotating universes are discussed: cosmological lens effect and cosmological mirror effect. 相似文献
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G.S.GOLITSYN 《大气科学进展》2009,(3)
The goal of this paper is to quantitatively formulate some necessary conditions for the development of intense atmospheric vortices. Specifically, these criteria are discussed for tropical cyclones (TC) and polar lows (PL) by using bulk formulas for fluxes of momentum, sensible heating, and latent heating between the ocean and the atmosphere. The velocity scale is used in two forms: (1) as expressed through the buoyancy flux b and the Coriolis parameter lc for rotating fluids convection, and (2) as expresse... 相似文献
3.
I. Brevik V. V. Obukhov A. V. Timoshkin Y. Rabochaya 《Astrophysics and Space Science》2013,346(1):267-271
Specific dark energy models with linear inhomogeneous time-dependent equation of state, within the framework of 4d Friedman-Robertson-Walker (FRW) cosmology, are investigated. It is demonstrated that the choice of such 4d inhomogeneous fluid models may lead to a brane FRW cosmology without any explicit account of higher dimensions at all. Effectively, we thus obtain a brane dark energy universe without introducing the brane concept explicitly. Several examples of brane Rip cosmology arising from 4d inhomogeneous dark fluid models are given. 相似文献
4.
Turbulence in an atmosphere with a non-uniform temperature 总被引：5，自引：4，他引：1
A. M. Obukhov 《Boundary-Layer Meteorology》1971,2(1):7-29
In this work the effect of static stability on the development of atmospheric turbulence is investigated. This influence is considered quantitatively by generalizing Prandtl's semi-empirical theory, i.e., by using a correcting factor in the form of a universal function of the Richardson number. An evaluation of the thickness of the layer of dynamic turbulence under various external conditions is successfully achieved quantitatively.In 1947 this Institute was transformed into Geophysical Institute. The latter in 1956 was divided into three parts, in one of which (Institute of Atmospheric Physics of the Academy of Sciences of the U.S.S.R.) A. M. Obukhov is serving as Director. 相似文献
5.
We investigate the dynamic aspects of rotating and expanding cosmologies. Exact solutions of GR and ECSK equations are obtained. Cosmological scenarios are presented for the rotating universe. The common features and some distinctions are found between the FRW and rotating expanding models. 相似文献
6.
We investigate specific models for a dark energy universe leading to Quasi-Rip and Pseudo-Rip cosmologies. In the Quasi-Rip model the equation of state parameter w is less than ?1 in the first stage, but becomes larger than ?1 in the second stage. In the Pseudo-Rip model the Hubble parameter tends to a constant value in the remote future, although w is always less than ?1. Conditions for the appearance of the Quasi-Rip and the Pseudo-Rip in terms of the parameters in the equation of state are determined. Analogies with the theory of viscous cosmology are discussed. 相似文献
7.
Andrey N. Makarenko Valery V. Obukhov Iliy V. Kirnos 《Astrophysics and Space Science》2013,343(1):481-488
We discuss the cosmological reconstruction in modified Gauss-Bonnet (GB) gravity. It is demonstrated that the modified GB gravity may describe the most interesting features of late-time cosmology. We derive explicit form of effective phantom cosmological models ending by the finite-time future singularity (Big Rip) and without singularities in the future (Little Rip). 相似文献
8.
Prokopyev Ilya R. Doroshkevich Anna G. Redina Anna A. Obukhov Andrey V. 《Mineralogy and Petrology》2018,112(2):257-266
Mineralogy and Petrology - The Ust-Chulman apatite ore body is situated within the Nimnyrskaya apatite zone at the Aldan shield in Russia. The latest data confirm the carbonatitic origin of the... 相似文献
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E. Elizalde A. N. Makarenko S. Nojiri V. V. Obukhov S. D. Odintsov 《Astrophysics and Space Science》2013,344(2):479-488
Multiple ΛCDM cosmology is studied in a way that is formally a classical analog of the Casimir effect. Such cosmology corresponds to a time-dependent dark fluid model or, alternatively, to its scalar field presentation, and it motivated by the string landscape picture. The future evolution of the several dark energy models constructed within the scheme is carefully investigated. It turns out to be almost always possible to choose the parameters in the models so that they match the most recent and accurate astronomical values. To this end, several universes are presented which mimic (multiple) ΛCDM cosmology but exhibit Little Rip, asymptotically de Sitter, or Type I, II, III, and IV finite-time singularity behavior in the far future, with disintegration of all bound objects in the cases of Big Rip, Little Rip and Pseudo-Rip cosmologies. 相似文献