[Show abstract][Hide abstract] ABSTRACT: Recent discussions of the origins of the thermodynamical asymmetry ("the arrow of time") by Huw Price and others are critically assessed. This serves as a motivation for consideration of relationship between thermodynamical and cosmological causes. Although the project of clarification of the thermodynamical explanandum is certainly welcome, Price excludes another interesting option, at least as viable as the sort of Acausal-Particular approach he favors, and arguably more in the spirit of Boltzmann himself. Thus, the competition of explanatory projects includes three horses, not two. In addition, it is the Acausal-Particular approach that could benefit enormously from dissociation from fanciful ideas of low-entropy future boundary conditions entertained by Price. Novel revolutionary developments in observational cosmology, as well as in the nascent astrophysical discipline of physical eschatology, have obliterated such hypotheses. Also, the Acausal-Anthropic approach we propose, offers another clear instance of disteleological nature of the anthropic principle.
[Show abstract][Hide abstract] ABSTRACT: The so-called Doomsday Argument has attracted a lot of attention in
recent years. One of the suggested ways to make this argument
ineffective is the so-called No-Outsider requirement, indicating that
the presence of other intelligent observers ('aliens') beside humans
invalidates the reasoning leading to the apocalyptic conclusion.
Obviously, this argumentation bears relevance not only to the
effectiveness of the Doomsday Argument, but also to the issues like the
relativization of the reference class in anthropic reasoning,
transhumanism and the SETI theory. Hereby we criticically investigate
the No-Outsider Requirement and conclude that it is either fallacious or
[Show abstract][Hide abstract] ABSTRACT: We investigate the impact of recent observational advances in research on the gaseous content of the universe on our knowledge of star formation histories of disk galaxies. Several contemporary surveys indicate that large quantities of gas which has not been astrated or has been astrated only weakly are bound to galaxies at later epochs ($z\le 1$).
[Show abstract][Hide abstract] ABSTRACT: One of the biggest obstacles to our full understanding of the global dynamics in Milky Way and other spiral galaxies is uncertainty with respect to the form of baryonic dark matter in galactic haloes. Two basic forms discussed recently are MACHOs and various states of halo gas. We investigate constraints which could be obtained from the empirical microlensing optical depth on combined MACHO + gas models, and show that improved statistics will certainly be able to discriminate between various such models. This has profound consequences not only for galactic dynamics and baryonic budget, but for investigation of the low-redshift Ly$\alpha$ absorption systems and general cosmological distribution of gas.
[Show abstract][Hide abstract] ABSTRACT: Microlensing observations can be used for determining the shape of the Milky Way's halo. It can be shown that the data are best described with moderately flattened halo, 0.5 < q < 0.6. We discuss, by taking into account this result, the constraints on the baryonic mass-density parameter, $\Omega_B$, and their implications on the value of the Hubble constant $H_0$, i.e. $h$. Our conclusion is that current data, in order to satisfy BBNS and Galaxy dynamics constraints, strongly suggest that $h$ should take values within the lower part of the permissible range, $h\sim 0.5$.
[Show abstract][Hide abstract] ABSTRACT: In this paper we present the ionization in the center of the Galaxy. We use Taylor & Cordes (1993) and Lazio & Cordes (1998) models to obtain the overall contribution of the Galactic center (GC) component to the total electron density. We also discuss local contributions from the GC area that come from a complex set of sources. Finally, we discuss the nature of SgrA*.
[Show abstract][Hide abstract] ABSTRACT: We study the ionizing sources in spiral galaxies and examine in more detail our Galaxy. Using Taylor & Cordes (1993) model we analyze the electron density in different parts of the Galaxy, and emphasize the still unsolved problems. Finally, we compare the intensities of H$\alpha$ emission in disk and halo.
[Show abstract][Hide abstract] ABSTRACT: We review recent research on the Milky Way galaxy and try to investigate whether its shape is similar to other barred galaxies. The emphasis is given on microlensing research because this method can be useful in determining the shape of the Galaxy with the minimal set of assumptions. By analyzing plots of the microlensing optical depth, $\tau$ as a function of galactic coordinates for different values of the axis ratio, $q$ of the galactic halo, we have shown that observations are best described by a flattened halo with $0.2 ^<_\sim q ^<_\sim 0.6$.