The Big Bang theory says nothing about what banged, why it banged, or what happened before it banged. – Alan Guth
If we chance to look at a cloudless night sky, studded with stars and occasional planets we may marvel at the expanse that penetrates beyond the apparent celestial limits as far as our eyes can penetrate. Then, inevitably, even without being a profound philosopher or a probing physicist a question often arises: How and when did this cosmic expanse, cluttered with countless stars and planets, came to be? This puzzlement has teased the minds of countless thinkers over many generations since antiquity.
Remarkably, it has been answered by many in a variety of ways. Some ancient minds thought of a Cosmic Architect whose magnificent Creation is what our wide, wide world is. That Creator has been conceived in a variety of ways and given a variety of names and forms. Some even told us in detail how its was done. Whether one describes those answers as musings or mythology, poetry or philosophy, speculation or scripture, recognitions or revelations, they have invariably carried great weight and wisdom, and appealed to millions of people in various cultures. These visions of how the world arose were seldom viewed as fantasies, often were sources of fulfillment.
Then emerged a new era in human understanding of the world beyond: the era of modern science and telescopes. Little by little our view began to expand and gradually change. Before long it was realized that we are not really at the center of the universe. Even our sun is just an insignificant star in a vast agglomeration of stars called the Milky Way. Difficult as it was to accept extreme insignificance is our grandiose universe, carefully acquired knowledge gave us little alternative. In the meanwhile sharper optical devises spotted many Milky Ways beyond our own: They came to be called galaxies: incredibly vast collections of stars, like sands on a beach, held together by the invisible gravitational glue. This was roughly the picture by the close of the nineteenth century.
In the 1929 it was discovered (by Edwin Hubble et al.), by careful observations, that many distant galaxies are receding away from our own, like ink spots on the surface of a balloon that is being blown. This was in accordance with the idea of an expanding universe suggested by Georges Lemaître a few years earlier. Indeed, the farther the galaxy, the faster it is scooting away. The fantastic idea of an expanding universe: had never before been thought of even in our most imaginative mythologies.
This means that in the past when the galaxies were much closer. Stretching our imagination this way we well picture a time when they were all closer and closer together. This way Lemaître took us to a moment when all galaxies were tightly packed together in what he called a Primeval Atom from which , the whole mammoth mass burst forth as a stupendous splash. In 1949, Fred Hoyle who thought this was a funny idea, caricatured it as a Big Bang: and the name struck. So it was that in 2019, exactly 70 years ago the birth of the material universe came to be described by this catchy phrase.
In the meanwhile, explorations in biology led to ideas of how the first self-replicating molecules might have been synthesize from the salts of the sea, instigated by lightning and heaven knows what other catalysts. All of a sudden (terrestrial) Life came to be. Similar syntheses might/could have elsewhere among the stellar billions in other planetary niches. Since Life is altogether different from its raw chemical components, it is appropriate to refer to the genesis of Life as the Second Big Bang.
Then, after some eons, life had evolved so much that some life forms became self-aware. The emergence of awareness or consciousness is another fantastic stage in the evolution of the Cosmos: so radically new in cosmic history and adding an element which makes the universe know itself that it deserves to be called the Third Big Bang.
So, in the vocabulary of our times we may speak of three major Big Bangs that occurred in cosmic history resulting in the emergence of: the physical world, the biological world, and consciousness. There are satisfactory scientific theories to explain the first two. At this point there are no universally accepted scientific theory for the third, though good efforts are being made in this field. Roger Penrose’s Quantum tubules to explain consciousness are as yet only as hypothetical as John Wheeler’s wormholes to interpret the solutions of Einstein’s gravitational equations.