Infinite universe

Singer, Dorothea Waley. Giordano Bruno his life and thought. With annotated translation of his work, On the infinite universe and worlds. New York London ... 

A study of Dijksterhuis s "The mechanization of the world picture" (1959), Koyre s "From the closed world to the infinite universe" (1957), and Yates s "Giordano Bruno and the hermetic traditon" (1964)... 

The critical density is traditionally dehned as that density which separates the closed (finite) universe from the open (infinite) universe in the simplest model available, i.e. in a universe without cosmological constant or quintessence. It corresponds to a universe with zero total energy, where the kinetic energy due to expansion is exactly balanced by gravitational potential energy. The value of the critical density is 10 gcm, which amounts to very httle when compared to a chunk of iron ... 

The philosophical appeal of curved space cosmology is that it allows a closed, rather than an infinite, universe. Experimental proof is in the observation of universal background radiation with a Planckian frequency distribution (Figure 2.5). Conjectural implications of closed space-time have been considered before [7, 62, 49]. 

As an aside, consider an infinite universe. They sky would be very bright, but not infinitely bright. Beyond a certain distance, the surface areas of the stars appear to touch and make a shield. Using these assumptions, we obtain a total flux 100,000 times as intense as the Sun s. See Reeves, Atoms of Silence, 230-231, for more information. 

Several numerical measures of the patterns can be computed and displayed in an effort to quantify the stmcture of the patterns. If these parameters are found to correlate with the beauty of certain patterns, computer programs can then examine these parameters and automatically generate classes of patterns of aesthetic value. Imagine sitting back and letting your computer scan an infinite universe of forms and display only those you will find attractive. 

A common simplifying assumption is that matter is distributed uniformly throughout the universe, subject to gravitational interaction. On this basis Newton could argue that in a universe of limited size all matter would eventually clump together in a central mass. Dynamic equilibrium, as observed, can only develop in an infinite universe. The resultant gravitational field should vanish everywhere, but local instabilities can give rise to the formation of stars and solar systems. The metric of such a system is clearly Euclidean. 

The topology of space-time is not as arbitrary as often made out. The theory of relativity unequivocally specifies a manifold of more than three equivalent coordinate axes with positive curvature. Infinite universes with negative or zero curvature are therefore excluded immediately. This limitation was recognized early on by Chfford (1955) ... 

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