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[en] The volume contains the material of an interdisciplinary evolution symposium. The purpose was to shed some light on possible connections between steps of evolution of matter on different levels of organisation. The topics involved are as follow: cosmogenesis; galactic and stellar evolution; formation and evolution of the solar system; global atmospheric and tectonic changes of Earth; viral evolution; phylogeny and evolution of terrestrial life; evolution of neural system; hominization. The material also includes some discussions of the underlying phenomena and laws of nature. (author)
[en] It is illustrated that a theoretical understanding of the formation and evolution of galaxies depends on an understanding of star formation, and especially of the factors influencing the rate of star formation. Some of the theoretical problems of star formation in galaxies, some approaches that have been considered in models of galaxy evolution, and some possible observational tests that may help to clarify which processes or models are most relevant are reviewed. The material is presented under the following headings: power-law models for star formation, star formation processes (conditions required, ways of achieving these conditions), observational indications and tests, and measures of star formation rates in galaxies. 49 references
[en] The Möbius form of the BFKL kernel in the next-to-leading order (NLO) in theories containing fermions and scalars in arbitrary representations of the colour group is presented. The ambiguity of the NLO kernels permits to get agreement between the BFKL approach and the colour dipole model and to find the quasi-conformal representation of the BFKL kernel.
[en] A new theory of the population of the Galaxy, based on the hypothesis of explosive: simultaneous and one-time-origination of life in the universe at a certain moment of its evolutionary development, is discussed in the report. According to the proposed theory, civilizations began to arise around the present moment of the history of the universe. Their possible number is limited even when their lifetime is unlimited. The age and number of simultaneously existing civilizations when their lifetime is unlimited is determined by the duration and dispersion of the time of evolution of life on different planets from the cell level to civilization. The proposed theory explains better than Drake's theory the negative results of the search for evidence of the existence of superpowerful extraterrestrial civilizations and the noncolonization of the earth
[en] Upcoming next generation galactic surveys, such as Gaia and HERMES, will deliver unprecedented detail about the structure and make-up of our Galaxy, the Milky Way, and promise to radically improve our understanding of it. However, to benefit our broader knowledge of galaxy formation and evolution we first need to quantify how typical the Galaxy is with respect to other galaxies of its type. Through modeling and comparison with a large sample of galaxies drawn from the Sloan Digital Sky Survey and Galaxy Zoo, we provide tentative yet tantalizing evidence to show that both the Milky Way and nearby M31 are undergoing a critical transformation of their global properties. Both appear to possess attributes that are consistent with galaxies midway between the distinct blue and red bimodal color populations. In extragalactic surveys, such 'green valley' galaxies are transition objects whose star formation typically will have all but extinguished in less than 5 Gyr. This finding reveals the possible future of our own galactic home and opens a new window of opportunity to study such galactic transformations up close.
[en] In this paper, the observational data relating to the early evolution of the Galaxy are reviewed in order to assess the plausibility of a number of models that have been proposed for the first stars. On the basis of standard fragmentation models, it is argued that primordial stars were very similar to normal stars, but that in some circumstances the formation of low mass primordial stars may be suppressed through the dissociation of molecular hydrogen by UV radiation. The existence of these conditions at the time of formation of the Galaxy could explain the absence of zero-metal stars. (orig./WL)
[en] Review of recent theorical and observational works on the galaxies (Time-scale of halo and disc formation, shape and dynamics of elliptical galaxies, remark on the density wave theory and the stochastic formation in spiral galaxies, detection of halos, dynamics of bars, dynamical interaction between galactic subsystems, mergers and dynamical friction). Possible influence on the evolution of stellar populations
[fr]Revue de developpements theoriques et de faits observationnels recents relatifs a la dynamique des galaxies (echelle de temps de formation du halo et du disque galactique, forme et dynamique des galaxies elliptiques, remarques sur les ondes de densite et la formation stochastique dans les spirales, detection des halos, dynamique des barres, interactions dynamiques entre composantes galactiques, coalescence des galaxies et friction dynamique). Incidences possibles sur l'evolution des populations stellaires
[en] There are three principal pieces of evidence which, when taken together, support the notion that the Universe as a whole is evolving. These are: (a) the Hubble velocity-distance relationship; (b) the abundance of light elements in the Universe; and (c) the three degree cosmic background radiation. The best explanation of these observations is that the Universe began, if it had a beginning, in a hot dense state and it has been expanding and cooling down ever since. In the course of that process matter came to be out of energy, galaxies and stars formed, and you and I came to exist. In this process the emergence of organic material in general, and human beings in particular, seems to have required a very fine tuning of the evolutionary process itself. We do not yet have a definitive scientific explanation of that fine tuning and, therefore, we do not yet understand the linkage of the human being to cosmic evolution. But some interesting suggestions can be made. (author). Abstract only
[en] The observed spectrum of the extragalactic background light in the range from ultraviolet to optical wavelengths is compared with a model prediction. The model uses the locally observed luminosity function of galaxies as well as evolutionary models for galaxy spectral energy distributions. The predicition is too faint by a factor of about 10. (author)