The big bang theory, something controversial only among American creationists, is seen by scientists as a fact about how the universe began. The only question that remains is perhaps why the big bang occurred and what the ultimate fate of the universe may be.We live in a remarkable time when these questions may finally be answered. It was only 20 years ago when the famed Stephen Hawking wrote his book A Brief History of Time, a book in which he discussed the possible fates of the universe: Will it expand forever, or will it collapse back in on itself?
The latter possibility brought with it a great deal of mind-bending concepts, and it was the possibility that Hawking favored on theoretical grounds at the time. He saw a universe which had always existed for all time, and the big bang was just one point in an endless cycle of universal death and rebirth.
When the big bang theory is viewed in this way, the universe starts off with a big bang and begins expanding. If the laws of physics allow it, stars, galaxies and planets will form, many of them presumably graced with life. The universe will expand to a certain maximum point at which the combined gravity of everything in it takes over, causing it to begin to collapse back down. In a process that reverses everything that happened up to this point, the universe will shrink back down to a point. Scientists called this the "big crunch". From here, the universe will rebound in another big bang and expand once more in a new cycle.
One aspect of this theory is that the universe can exist independently of anything else. The mind bending question of where the universe came from has no meaning-it has always been here. As Hawking talks about in his book-if the universe is this way there really isn't anything for a God to do. Proving the universe followed this kind of cycle would in effect be proof for the position of atheism.
The theory also left room for some bizarre consequences. For example, would time run backwards during the collapse? Or how about this: is the universe doomed to endlessly recycle everything? In other words the universe is born in a big bang, expands to the maximum point, and then collapses only to replay the same story again. As the universe collapses it would play out a bizarre world that makes no sense to human consciousness as time flowed backward, your life ran backward and effects preceded causes. Each time through the cycle, at the same point you appeared before, you would live out your life once more in deterministic fashion completely unaware of the trillions of trillions of times this all happened before, and would happen endlessly in the future.
Or how about this. Maybe at the "cusp", the point between collapse and renewed expansion, the laws of physics are scrambled, and each time a completely new kind of universe is born.
Another possibility-the laws of physics are the same, but the universe just plays out a similar, but different history. This has happened an infinite number of times, so infinite numbers of intelligent beings and civilizations have arisen, only to be completely destroyed-all evidence of them and whatever they learned erased-at the next crunch-bang cycle.
All of this was put to moot when the big bang theory took a new twist in the late 1990s. It was then that astronomers discovered that not only was the universe expanding, but that expansion is accelerating. It now seems that as time goes on, the universe will expand faster and faster so that clusters of galaxies will simply get further and further away from each other as time goes on. There is no chance for gravity to pull back on the universe and cause it to collapse. The universe, it seems, is destined to simply cool off and fade away, to die and ice cold death in a dark world where life is no longer possible.
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