Related papers: Dark Matter and Cold Fractal Clouds
There are a number of theoretical and observational hints that large numbers of low-mass galaxies composed entirely of dark matter exist in the field. The theoretical considerations follow from the prediction of cold dark matter theory that…
We propose experimental schemes for detection an axionic condensate supposed to be cosmic dark matter. Various procedures are considered in dependence on the value of the axion mass. There are well known indications that a large part of the…
Dark matter has been introduced to explain many independent gravitational effects at different astronomical scales, in galaxies, groups of galaxies, clusters, superclusters and even across the full horizon. This review describes the…
Newtonian mechanics indicates that galaxies and galaxy clusters are much more massive than we would have guessed from their luminosities, with the discrepancy being generally attributed to dark matter halos. An alternative hypothesis is…
Molecular hydrogen clouds can contribute substantially to the galactic halo< dark matter and may lead to the birth of massive halo objects (MHOs) observed indirectly by microlensing. We present a method to detect these molecular clouds in…
A galactic disk in a spiral galaxy is generally believed to be embedded in an extended dark matter halo, which dominates its dynamics in the outer parts. However, the shape of the halo is not clearly understood. Here we show that the dark…
I give a review of the development of the concept of dark matter. The dark matter story passed through several stages from a minor observational puzzle to a major challenge for theory of elementary particles. Modern data suggest that dark…
The distribution of the stellar and gaseous components in low surface brightness galaxies has been determined directly from optical and HI imaging. The distribution of what might be the dominant mass component, the dark matter, which is…
Dark matter has been introduced to explain mass deficits noted at different astronomical scales, in galaxies, groups of galaxies, clusters, superclusters and even across the full horizon. Dark matter makes itself felt only through its…
Sahu et al. recently reported tentative evidence for a large population of "free-floating" planetary-mass objects in a nearby globular cluster. If verified, this discovery is consistent with a prediction that the galactic dark matter has a…
Recent work on the mass distribution in spiral galaxies, using mainly HI observations, is reviewed. The principal problem is still to determine to what extent the dark matter is important in the inner parts of a galaxy, or in other words,…
Mysterious dark matter constitutes about 85% of all mass in the Universe. Clustering of dark matter plays the dominant role in the formation of all observed structures on scales from a fraction to a few hundreds of Mega-parsecs. Galaxies…
In this short note we discuss recent observation of linear correlation on log-log scale between distribution of dark and visible mass in gravitationally bound systems. The coefficient of such correlation appears to be essentially the same…
We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…
After two decades of efforts to identify the enigmatic dark matter that comprises the dominant form of matter in our galaxy, the mass range for viable candidates appears to have been reduced by more than 50 orders of magnitude. Positive…
The nature of the cosmological dark matter remains elusive. Recent studies have advocated the possibility that dark matter could be composed of ultra-light, self-interacting bosons, forming a Bose-Einstein condensate in the very early…
Several lines of evidence suggest that some of the dark matter may be non-baryonic: the non-detection of various plausible baryonic candidates for dark matter inferred, e.g., from galaxy rotation curves and from cluster of galaxy velocity…
An overview is given of various dark matter candidates. Among the many suggestions given in the literature, axions, inert Higgs doublet, sterile neutrinos, supersymmetric particles and Kaluza-Klein particles are discussed. The situation has…
In this paper we review the main and the most recent evidence for the presence of a core radius in the distribution of the dark matter around spiral galaxies. Their rotation curves, coadded according to the galaxy luminosity, conform to an…
The origin of dark matter in the universe may be weakly interacting scalar particles produced by amplification of quantum fluctuations during a period of dilaton-driven inflation. We present two interesting cases, the case of small…