Mar 4, 2007
Every mountain, river, and valley; all the birds and human beings, the Sahara desert… all that was, that is, and will be, was at one time united in a single tiny and fiery point. So infinitely dense and fiery that our mortal imagination will perhaps never be able to comprehend it all. Millions of billions of tons of matter together with all the energy of the great universe, beginning to expand and break apart in an enormous explosion about 20 000 million years ago.
Compared with this big "Bang", the noise of our most powerful atomic bombs would be, at most, equal to a mosquito falling to the ground on the other side of the Earth. From that point on, the history of the cosmos took an even richer and more curious turn. The constant expansion of all that exists made the universe turn into a state of plasmic soup, gradually transforming towards a state more and more similar to what we know today. The matter slowly cooled down, and then formed the first quarks, electrons and protons. 300 000 years passed, electrons and nucleuses combined to form atoms, and later formed quasars, stars, groups of galaxies, and all that is our now familiar, though still in great part unknown, universe.
Despite all the information obtained through years of scientific investigation, the phases of the universe during the first moments after the great explosion are still the subject of heated debate. The diverse theories that circulate in scientific circles seem to unravel when trying to explain the particular quantum state of matter in the primitive phases—the very first moments of the "Big Badaboom." There still does not exist a single convincing physical model to explain the first 10 -33 seconds of the universe.
Trying to understand the origin of the big explosion is even more complex. The more we understand the first cause of each thing, and come to realise more and more that all things follow from prior causes, the reason the universe was created seems to transform itself into an even greater enigma; the ultimate truth to unveil.
A theory being reconsidered nowadays to explain the ultimate origin is the Oscillating Universe. Many scientists estimate that the matter contained in the universe is sufficient to achieve a gravitational force great enough to stop further expansion and begin, at a determinate time in history, reversing the process.
According to reason, this constant contraction of the whole universe would culminate at a single, primordial point—a phenomenon named the "Big Crunch." From this moment on (of course, theoretically) the universe would literally continue on in same way, with a "Big Bounce;" that is to say, a new Big Bang. This theory leads us to question whether this extraordinary chain of events (generation-degeneration-destruction) is repeated eternally, and whether it has already been repeating infinitely into the distant past.
In spite of the Oscillating Universe at one time being strongly rejected in place of other models of the universe, recent studies have appeared which argue in favour of this theory. Investigators of Penn State University have speculated about the possible history of the universe before the Big Bang using quantum gravitational calculations.
According to these calculations, before the Big Bang there existed a state of space-time similar to ours, though in the stage of contraction. It is thought that the gravitational forces pulling the universe inward reached a certain point such that the quantum properties of space-time caused gravity to become repulsive, rather than attractive, producing the Big Bang from which we now suppose ourselves to have come.
The variation of the cosmological constant alpha, a strange fact that was considered revealing to scientists in recent years, could also be related to the matter of previous universes. This abstract value (alpha)—taken as a parameter of the universal laws that permit atoms to be maintained in unity, also underlying the laws of chemistry as we understand them—does not coincide with that we would expect from a universe with an age such as ours.
According to the current value of alpha, the universe should be some 14 thousand million years older than it is, and matter should be much more dispersed than it now is. The scientists Paul Steinhardt from the University of Princeton, U.S. and Neil Turok from the University of Cambridge in the U.K. give their opinion with regard to the cyclical theory which could well explain this anomaly of the alpha constant—that there would have been time enough for the measured value to be such as it is if it had existed prior to our universe, perhaps in a previous universe.
Even were the theory of the cyclical universe to be proven, and supposing that we came from a prior Big Crunch, the cause of the explosion that gave origin to the cycle of indefinite expansions and contractions remains a mystery. The model of cosmic cycles proposed in the Big Bounce could not have an endpoint, but, it may be posited, must have a beginning. Does this origin become the frontier between science and religion? Do "divine" factors underlie the origin of space and time, or will we some day be able to explain everything, and the cause of the Big Bang, in a completely scientific way?
Contemporary science has guided us toward calculations that approach (though with increasing difficultly) the principle elements of the Big Bang, notwithstanding the possibility that it will never be permitted for us humans to know the final truth. And even though many scientists theorize that the universe that we inhabit does not contain anything beyond the horizon of science, nor a time "before" its time, we must surely agree that no human being can escape the temptation of asking themselves, sometimes, just what it was which caused "all that exists." Whatever the case, through reason or through science, the return to the origin has already begun.