Spherical Shell Cosmological Model and Uniformity of Cosmic Microwave Background Radiation

Considered is spherical shell as a model for visible universe and parameters that such model must have to comply with the observable data. The topology of the model requires that motion of all galaxies and light must be confined inside a spherical shell. Consequently the observable universe cannot be defined as a sphere centered on the observer, rather it is an arc length within the volume of the spherical shell. The radius of the shell is 4.46 $\pm$ 0.06 Gpc, which is for factor $\pi$ smaller than radius of a corresponding 3-sphere. However the event horizon, defined as the arc length inside the shell, has the size of 14.0 $\pm$ 0.2 Gpc, which is in agreement with the observable data. The model predicts, without inflation theory, the isotropy and uniformity of the CMB. It predicts the correct value for the Hubble constant $H_0$ = 67.26 $\pm$ 0.90 km/s/Mpc, the cosmic expansion rate $H(z)$, and the speed of the event horizon in agreement with observations. The theoretical suport for shell model comes from general relativity, curvature of space by mass, and from holographic principle. The model explains the reason for the established discrepancy between the non-covariant version of the holographic principle and the calculated dimensionless entropy $(S/k)$ for the visible universe, which exceeds the entropy of a black hole. The model is in accordance with the distribution of radio sources in space, type Ia data, and data from the Hubble Ultra Deep Field optical and near-infrared survey.Comment: 7 pages 2 figures, Conference: Low Dimensional Physics and Gauge Principles, Yerevan, Armenaia, September 21-26, 201

Uniformity of Cosmic Microwave Background as a Non-Inflationary Geometrical Effect

The conventional $\Lambda$CDM cosmological model supplemented by the inflation concept describes the Universe very well. However, there are still a few concerns: new Planck data impose constraints on the shape of the inflaton potential, which exclude a lot of inflationary models; dark matter is not detected directly, and dark energy is not understood theoretically on a satisfactory level. In this brief sketch we investigate an alternative cosmological model with spherical spatial geometry and an additional perfect fluid with the constant parameter $\omega=-1/3$ in the linear equation of state. It is demonstrated explicitly that in the framework of such a model it is possible to satisfy the supernovae data at the same level of accuracy as within the $\Lambda$CDM model and at the same time suppose that the observed cosmic microwave background (CMB) radiation originates from a very limited space region. This is ensured by introducing an additional condition of light propagation between the antipodal points during the age of the Universe. Consequently, the CMB uniformity can be explained without the inflation scenario. The corresponding drawbacks of the model with respect to its comparison with the CMB data are also discussed.Comment: 23 pages, 4 figure

Zero average values of cosmological perturbations as an indispensable condition for the theory and simulations

We point out a weak side of the commonly used determination of scalar cosmological perturbations lying in the fact that their average values can be nonzero for some matter distributions. It is shown that introduction of the finite-range gravitational potential instead of the infinite-range one resolves this problem. The concrete illustrative density profile is investigated in detail in this connection.Comment: 5 pages, 2 figure

COMPETITIVENESS OF WINE EXPORT FROM THE REPUBLIC OF SERBIA

The authors of this paper analyze export and competitiveness of wine export from the Republic of Serbia. Main goal of the research reflects in perceiving basic features of export and competitiveness of wine export from the Republic of Serbia on international market. The analysis encloses time period 2004-2007. The amount of wine export is very modest and, in observed period, was realized average export of 8,6 million litres, which value amounts 9,6 million USD. Only 5% of total domestic production is exported. In export structure dominate CEFTA agreement signatory countries. Export price of wine from Serbia is doubly less in regard to average world price, and thrice in regard to the biggest world exporter – Italy. Average export price of wine produced in Serbia is on the level of 1,11 USD per litre. The export structure is very unfavourable, i.e. dominates wine in bulk (90%), while only 10% of total export makes wine in bottles, which, for sure, reflects to attained export price. The authors quote that main limitation factors of Serbian wine export are small surfaces under grapevine, inappropriate structure of production, i.e. lack of qualitative and top-class (famous) wines. The wines which produce in Serbia, on international market, are competitive by price. However, low quality represents limitation factor of competitiveness increase. Unfavourable production structure and wine export represents one more limitation factor of competitiveness increase. In total wine production in Serbia, top-class wines participate with less than 15%, participation of qualitative wines is 20%, while the higher participation, more than 65%, have table wines, and more produces white (64%) than rose wines (36%). Previously mentioned is in opposition with demand trends on international market. Along with quality increase and change of production and export structure, there can be expected also increase of Serbian wine prices on international market. Analyzing the world turnover of wine, the authors resolve that leading exporters of wine have developed production and long tradition in wine export. Besides, there are series of governmental stimulations, aiming at export increase, which is significant from aspect of competitiveness increase. The European Union has increased wine export quota from 55 to 63 thousand hectolitres to the Republic of Serbia for duty free export, and mentioned decision on export quotas increase represents an incentive for faster development of viticulture and wine production in Serbia. As an imperative, the authors quote increase of high-quality wines participation in export, which have higher price in regard to table wines. They find that own chance for export must not be looked-for in quantity, because Serbia is relatively small wine producer, concerning high quality according to selected market segments, but also that Serbia must leave the path of industrial wines and produces only high-quality wines. In this paper has been pointed out to necessary measures, aiming at more dynamic export and competitiveness increase of wine export from Serbia. The Authors find that main focus should be on intellectual capital, which means permanent education of producers, in order to get wines of the highest quality which will find their consumers in a competitive world market.wine, export, competitiveness, Agribusiness, Crop Production/Industries, International Relations/Trade,