Vacuum genesis
Encyclopedia
Vacuum genesis is a hypothesis
Hypothesis
A hypothesis is a proposed explanation for a phenomenon. The term derives from the Greek, ὑποτιθέναι – hypotithenai meaning "to put under" or "to suppose". For a hypothesis to be put forward as a scientific hypothesis, the scientific method requires that one can test it...

 about the Big Bang
Big Bang
The Big Bang theory is the prevailing cosmological model that explains the early development of the Universe. According to the Big Bang theory, the Universe was once in an extremely hot and dense state which expanded rapidly. This rapid expansion caused the young Universe to cool and resulted in...

 that states that the universe began as a single particle arising from an absolute vacuum, similar to how virtual particles come into existence and then fall back into non-existence.

The concept of vacuum genesis was first proposed in 1969 during a seminar being conducted by cosmologist
Cosmology
Cosmology is the discipline that deals with the nature of the Universe as a whole. Cosmologists seek to understand the origin, evolution, structure, and ultimate fate of the Universe at large, as well as the natural laws that keep it in order...

 Dennis Sciama. Edward Tryon
Edward Tryon
Edward P. Tryon is an American scientist from Terre Haute, Indiana and a professor of physics at Hunter College in Manhattan. His specialization is in theoretical quark models, theoretical general relativity, and cosmology. In 1973 he proposed that the universe is a large-scale vacuum energy...

, in the audience, was seized by an idea and blurted "Maybe the universe is a vacuum fluctuation." This was treated as a joke at the time, but Tryon hadn't been joking. In a 1984 interview, Tryon recalled that three years later, sitting at home, he had a further revelation; "I visualized the universe erupting out of nothing as a quantum fluctuation and I realized that it was possible that it explained the critical density of the universe."

The critical density of the universe is dependent upon the rate at which the universe is still expanding. The universe is expanding at an accelerated rate, but was originally thought to be slowing down, furthermore the rate at which this is changing gives the overall mass density of the universe which is denoted by the Greek letter omega. If omega is less than one, the mass density would be insufficient to stop the universe's expansion and it would go on expanding forever. If omega is more than one, the universe will eventually stop expanding and thus collapse in on itself to again form another fireball not unlike the one from which it came. If omega is exactly 1, the universe's expansion will continuously slow, but never quite halting. Tyron's speculation requires that omega be equal to or less than one. Thorough calculations it has been found that omega is, in fact, 1, or almost exactly 1.

This omega value gives an almost precise value of unity. This means that cosmic space is neither dramatically open or dramatically closed, but is almost perfectly flat.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK