Begin of the Univers


The noted scientific cosmologist, P. James E. Peebles, summed up the current state of this field by saying that at its heart is the solidly established big bang theory. But Peebles immediately cautioned, "That the universe is expanding and cooling is the essence of the big bang theory. You will notice I have said nothing about an "explosion" – the big bang theory describes how our universe is evolving, not how it began." To the big bang, he tells us, scientists are trying to add the theory of inflation, that is, that early in its life the universe expanded rapidly. There is also strong evidence that most of the mass of the universe cannot be accounted for by the things we see, but there must be some sort of unknown dark matter. Further, it appears that something, some dark energy or quintessence, is making the universe accelerate.

By 1929, however, the picture was changing. Edwin Hubble was discovering other galaxies, and found that the farther away they were, the more the light from them was shifted towards the red end of the spectrum, indicating that they were moving away and the universe was therefore expanding. And physicists like Alexander Friedmann and George Lemaître and others had uncovered Einstein’s apparent mistake. In 1965, two Bell Laboratory scientists, Arno Penzias and Robert Wilson, while trying to eliminate radio interference, discovered cosmic background microwave radiation left over from the big bang.
Now we are faced with a universe so big and so old that it defies our imaginations to grasp it. It appears to have begun 15 billion years ago. Our galaxy, alone, has some 100 billion stars, and it is just one of perhaps a 100 billion galaxies, and this immense universe is expanding at an ever increasing rate.

This is an awe-inspiring picture, but what does it say about the origin of the universe? Let’s imagine that the scientific cosmologists have been creating an ever more detailed and vivid movie of the structure and movement of the universe, and this film, when it is played backwards, makes the universe appear as if it is coming together and beginning in an intensely hot and dense state. But the real question is whether this movie takes us back to the absolute beginning, or very origin of the universe. It doesn’t appear to do so because the basic laws of nature, as described by Einstein’s relativity, break down as we approach this beginning. It is as if the film runs out and just before we reach the beginning we are dazzled with a blinding white light. And we are faced with the very difficult question: can science find a way to talk about the very beginning of the universe, or is this simply outside its scope?

The scientists, themselves, are divided about the matter. The physicist Charles Townes writes: "I do not understand how the scientific approach alone, as separated from a religious approach, can explain an origin of all things. It is true that physicists hope to look behind the ‘big bang,’ and possibly to explain the origin of our universe as, for example, a type of fluctuation. But then, of what is it a fluctuation and how did this in turn begin to exist? In my view, the question of origin seems always left unanswered if we explore from a scientific view alone." But other scientists are less reluctant to put science to the task and to try to develop a scientific theory of the beginning of the universe. Let’s look at some of these attempts.

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