Condensing the History of the Universe
When we learn that the age of the Universe is 13,800,000,000 years, it is difficult for us to wrap our minds around such a figure. Most of us are used to thinking of time in units that we can relate to our own lives. We tend to think of a decade as a long time. In the advanced nations, 75-80 years constitutes a normal lifespan. A century represents a very long time (or an extremely long life), and a millennium stretches our imaginations. To hear that the life of the Universe is, so far, 138,000,000 times longer than the life of a centenarian challenges our conceptual limits to the breaking point. Why does this matter? Because when we can no longer conceive of something, it becomes, in a sense, invisible to us, and hence meaningless. In order for us to make our place in reality mentally visible and meaningful we have to come up with a way of thinking about the unfolding events of the Universe that uses time frames with which we are intimately familiar. So how can this be done?
In his classic work, The Dragons of Eden: Speculations on the Evolution of Human Intelligence, the great Carl Sagan used an ingenious method to make the vast age of the Universe comprehensible. This method is known as “The Cosmic Calendar” and it is based on conceiving of the Universe’s history, from the Big Bang to this very moment, as having taken place in the span of just one Earth year. The first moment of the Universe’s existence, therefore, would be midnight, 1 January. The current moment would be midnight exactly one year later, right at the start of a new year. So, to measure the progress of the Universe from the earliest moment of its existence to the emergence of human consciousness, we would convert the real times of the most significant developments to our one year framework, always keeping these events in the correct proportional relationship to each other on our calendar.
Since some people think in a more linear way, I will also use the timeline concept I introduced in the chapter entitled A Species Lost in Both Space and Time. This involves, as I said, imagining there is a timeline stretching out 1,000,000 meters (1000 kilometers or 621.3 miles) before us, almost the exact distance between Darjeeling and Agra, India or between Cardiff in the United Kingdom and Magdeburg, Germany, or a little shorter than the distance between Chicago and Harrisburg, Pennsylvania. If the Big Bang is at the very beginning of the timeline and our lives at the very end, where do the great events that mark the progress of the Universe from the unconscious to the conscious fall?
The answers to these questions, as I indicated previously, are not flattering to human vanity. It is startling, as well, to see how near in time to us the age of the dinosaurs actually was, or how downright recent the evolution of the first primates was, perhaps a mere 65,000,000 years ago. On our chronology we will examine all the “firsts” in the prehistory of the world, explain something about the major events surrounding and proceeding from them, and try to elucidate how the physical, chemical, and biological realms produced an utterly unexpected offshoot—us.