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Modern concepts of the universe support the assumed existence of a nongravitational source, known as dark energy, for which
ε + 3 P < 0 (where ε is the energy density and P is the pressure). This ensures accelerated expansion of the universe. This paper examines a tensor-scalar
variant of the theory of gravitation with a conformally coupled scalar field. Various cosmological models are examined and
the possible evolutionary development of the universe with accelerated expansion is discussed.
Translated from Astrofizika, Vol. 51, No. 4, pp. 653–661 (November 2008). 相似文献
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V. G. Trifonov E. A. Shalaeva L. Kh. Saakyan D. M. Bachmanov V. A. Lebedev Ya. I. Trikhunkov A. N. Simakova A. V. Avagyan A. S. Tesakov P. D. Frolov V. P. Lyubin E. V. Belyaeva A. V. Latyshev D. V. Ozherelyev A. A. Kolesnichenko 《Geotectonics》2017,51(5):499-519
New data on the stratigraphy, faults, and formation history of lower to middle Pleistocene rocks in Late Cenozoic basins of northwestern Armenia are presented. It has been established that the low-mountain topography created by tectonic movements and volcanic activity existed in the region by the onset of the Pleistocene. The manifestations of two geodynamic structure-forming factors became clear in Pleistocene: (i) collisional interaction of plates due to near-meridional compression and (ii) deep tectogenesis and magma formation expressed in the distribution of vertical movements and volcanism. The general uplift of the territory, which was also related to deep processes, reached 350–500 m in basins and 600–800 m in mountain ranges over the last 0.5 Ma. The early Pleistocene (~1.8 Ma) low- and medium-mountain topography has been reconstructed by subtraction of the latest deformations and uplift of the territory. Ancient human ancestry appeared at that time. 相似文献
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Gravitational radiation in a variant of the bimetric theory of gravitation is investigated in the case of slow motions and weak fields. Questions of the propagation velocity, polarization, and generation of a weak gravitational wave are considered. The Peters-Matthews coefficients and the dipole emission coefficient are determined. 相似文献
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Cosmological solutions are examined in the proper representation of the JBD theory with a dominant nonminimally coupled scalar
field. It is shown that only the introduction of a cosmological scalar that transforms to the ordinary cosmological constant
in the Einstein representation enables a phase of evolution with a uniform and then an accelerated expansion of the universe
over cosmological time scales.
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Translated from Astrofizika, Vol. 48, No. 4, pp. 633–640 (November 2005). 相似文献
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Arshavir Avagyan Hasmik Manandyan Aleksandr Arakelyan Artak Piloyan 《Natural Hazards》2018,92(1):283-309
This paper presents the results of a research aiming natural and technological hazard, and risk assessment and mapping in Web-based holistic geographic environment, and the implementation of the Sendai Framework for Disaster Risk Reduction 2015–2030 in Armenia. A common spatial multi-criteria evaluation method was used for natural and technological hazard, risk and population vulnerability assessments. The virtual geographic environment developed by the authors during the previous period of investigations was upgraded and used for the implementation of this research. It involves the following components: 1. geodatabase, 2. modeling and simulation, 3. interface for digital mapping, 4. metadata, 5. Web–based network service for collaboration. Moreover, the country specific natural and technological hazard, risk and population vulnerability assessment methods were developed, implemented, and appropriate digital maps were created. 相似文献
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This paper is part of a series based on a modified Jordan tensor-scalar theory of gravitation. Given the current importance
of research on vacuum phenomena in cosmic evolution, we examine several standard cosmological models with a scalar field and
a physical vacuum, including models that have a dominant scalar field with the vacuum energy taken into account in various
conformal representations of the Jordan theory, as well as models in which ordinary matter that obeys the conventional equations
of state is present. Some noteworthy results are obtained which are, to a certain extent, consistent with currently available
observational data. 相似文献