The Big Bang Theory II

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And another explanation:

About 15 billion years ago a tremendous explosion started the expansion of the universe. This explosion is known as the Big Bang. At the point of this event all of the matter and energy of space was contained at one point. What exisisted prior to this event is completely unknown and is a matter of pure speculation. This occurance was not a conventional explosion but rather an event filling all of space with all of the particles of the embryonic universe rushing away from each other. The Big Bang actually consisted of an explosion of space within itself unlike an explosion of a bomb were fragments are thrown outward. The galaxies were not all clumped together, but rather the Big Bang lay the foundations for the universe.

As I said at the end of the other post, without dealing with where the matter came from before the explosion, its a pretty poor explanation for the beginnings of the universe. The matter had to come from something. If the thing that caused the universe is part of the universe, then the theory is quite useless for explaining the origins.

Since the Big Bang, the universe has been continuously expanding and, thus, there has been more and more distance between clusters of galaxies. This phenomenon of galaxies moving farther away from each other is known as the red shift. As light from distant galaxies approach earth there is an increase of space between earth and the galaxy, which leads to wavelengths being stretched.

In addition to the understanding of the velocity of galaxies emanating from a single point, there is further evidence for the Big Bang. In 1964, two astronomers, Arno Penzias and Robert Wilson, in an attempt to detect microwaves from outer space, inadvertently discovered a noise of extraterrestrial origin. The noise did not seem to emanate from one location but instead, it came from all directions at once. It became obvious that what they heard was radiation from the farthest reaches of the universe which had been left over from the Big Bang. This discovery of the radioactive aftermath of the initial explosion lent much credence to the Big Bang theory.

Even more recently, NASAs COBE satellite was able to detect cosmic microwaves eminating from the outer reaches of the universe. These microwaves were remarkably uniform which illustrated the homogenity of the early stages of the universe. However, the satillite also discovered that as the universe began to cool and was still expanding, small fluctuations began to exist due to temperature differences. These flucuatuations verified prior calculations of the possible cooling and development of the universe just fractions of a second after its creation. These fluctuations in the universe provided a more detailed description of the first moments after the Big Bang. They also helped to tell the story of the formation of galaxies which will be discussed in the next chapter.

The Big Bang theory provides a viable solution to one of the most pressing questions of all time. It is important to understand, however, that the theory itself is constantly being revised. As more observations are made and more research conducted, the Big Bang theory becomes more complete and our knowledge of the origins of the universe more substantial.

No it explains why the universe is expanding. Not how it was created.