The Shape of the Universe
Despite the fact that the universe has a clear structure, and also with several levels of hierarchy, the concepts of classical mechanics, such as the shape, weight, size, for it does not make sense: the universe with nothing interacts. Instead, it is described as a thermodynamic system, using concepts such as density, pressure, temperature, chemical composition. It is they who will shape the universe as a whole.
It is formed by multiple processes operating at different levels of hierarchy – scale, and have a different nature. The largest of them – is expansion of the universe, the nature of which – the gravitational interaction of all existing facilities. It is on its course to the future of the universe on the largest scales.
Another phenomenon, which is comparable in scale to the size of the universe, may be called the relic background. It consists of a photon emitted at a time when the light of the hot Big Bang practically ceased to interact with matter, separated from her. Now, because of the expansion of the universe visible most of the photons in the microwave radio band moved.
The hierarchy of scales in the universe
Gravity is also responsible for the formation of complex large-scale structures, Come, and superclusters, clusters, local group of galaxies, lenticular galaxies, irregular, elliptical and spiral galaxies with active nuclei, and so on. Each structure is a field in which the various processes unfold. Together they determine the evolution of individual galaxies – the basic process of morphological and chemical evolution of the universe. The main role is played on a smaller scale of star clusters, star systems with different degrees and, finally, individual stars.
The diagram below shows the complex processes that shape the evolution of the galaxy.
In the center of the diagram are important stages in the evolution of a star, from its formation to the death. Their course malozavisim what’s going on with the entire galaxy at large. However, the total number of newly formed stars and their parameters are subject to significant outside influence. Processes, the magnitude of which are comparable to or greater than the size of the galaxy (the diagram is all the rest, are not included in the central area), change the morphological structure, the rate of star formation, and hence the rate of the chemical evolution of the spectrum of the galaxy, etc.
As you can see, the scale of the processes – many millions of years, the context in which they occur very rarely, and then only in part, can be reproduced in the laboratory, so all knowledge of them – multi-interpretation of astronomical observations.