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.
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