We really don't know much about the way that the universe came into existence. The best we can do is to trace its evolution back to a time about 300,000 years after the big bang. Beyond this time, direct telescopic observation becomes impossible and we have to use other evidence to take us further back. So far, astronomers feel pretty certain that we have a consistent picture that goes back to about 1 second after the big bang during which time the primordial elements, hydrogen, deuterium, helium and lithium, were synthesized. We can even take our model of the big bang back a further step to about 1 microsecond after the big bang, because the essential physics of this state can be described by our well-tested model of sub-atomic physics called the Standard Model. At 1 microsecond, protons and neutrons dissolve into individual quarks, so the universe was a 'gas' consisting of quarks.
Still earlier, our modern theory of nuclear physics lets us see that there were probably several 'crystallizations' when the universe went through several phase transitions just as steam condenses to water then to ice as its temperature is lowered. The earliest one we know about is the so-called 'GUT' transition which occurred about 10^-35 seconds after the big bang. We do not of course know this for certain. All we can do is extrapolate the physics we do know, and observe in our Earth-bound laboratories, to similar conditions that Big Bang cosmology says occurred at a particular time.
Now, what started this whole process and where did THAT come from? We honestly do not know. Obviously we can never re-visit these conditions. And we will probably never have the technological resources to manufacture these conditions in our laboratories. All we can do is craft better and better theories that predict what these earliest conditions may have been like, and test these theories as best we can because they will also make predictions about what physicists should see happen in their particle accelerators at the highest energies we can achieve.
Why do we not simply throw up our hands and say that 'God' did it? Because that is not how science works. We are not after explanations that sound good, or make us feel happy, or satisfy some need we have as humans to see order and purpose in everything. The scientific process is after TESTABLE explanations that can be independently checked by people, regardless of their political, religious, or moral persuasion. Newton's Law of Gravity works whether you are an athiest or a devout Christian or Buddhist. We see the same 'laws' carrying us toward descriptions of the state of the universe less than 1 microsecond after the Big Bang. Right now, we have no reason to believe that the same process of inquiry, guided by the best observational and experimental evidence we can acquire, will not take us even closer to the moment when the universe came into existence. Why stop when we have only just begun?
Copyright (C) 1997 Dr. Sten Odenwald
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