8 :: “Our Place in the Universe(s)”
In this final lesson we’ll discuss how cosmology and the human experience fit together.
The First Cause
As you have seen, cosmology started out as the province of priests and philosophers. Over millennia, philosophy and cosmology have continued to dance together around the concepts of human origins, concrete existence, and now quantum mechanics. Atheists and deists alike have turned to science to either support or tear down the idea of God. People in search of a Star Trek future, rich in alien civilizations and brainy intergalactic dialogue, invoke both statistics and philosophy to declare that life must exist elsewhere. In this lesson we will explore — without trying to say who is right or wrong — the common borderlands of science, religion, and philosophy.
One of the biggest questions cosmology introduces is the question of origins. It is possible for theorists to create mathematical models of the big bang that include events only 10-43 of a second after the big bang and that make accurate, observed predictions about our current universe. What these theories don’t do is explain how the universe began in the first place.
The standard big bang model says that at the beginning of time the universe was composed of a single singularity — infinitely small and with infinite curvature — that contained all the matter and energy of the current universe. What created this system and what caused this system to explode out to create our universe are questions beyond the realm of classical physics and general relativity.
Quantum mechanics theory hints at some possible solutions. Stephan Hawking and James Hartle developed a model that describes the universe as a closed wave function in which space and time are entwined, there is nothing outside the universe, and there is no beginning to time. Rather, with the correct initial conditions, their wave function reduces the universe to burbling quantum foam. Just as a circle has no beginning, the four-dimensional wave function of our universe has no beginning in this model.
The Hawking-Hartle wave function is compatible with inflationary models for the early universe. It is also compatible with many-universe inflationary models. Russian-born theorist Andrei Linde has proposed that the scalar field that triggered the inflationary epoch of our own universe is but one of many such fields that exist in a chaotic, bubbled tangle. Freezing out a field in one place amplifies the field in another, creating new inflation and the formation of new bubble universes. Our universe is just one bubble among countless others. Each field has its own set of parameters and some, unlike our own, inflate at exponential rates forever.
Linde’s theory does two things: It removes the question of what caused the big bang and it mitigates concerns about our universe having had an improbably perfect set of initial parameters. Many scientists have looked at how precisely factors such as the amount of dark matter and the values of certain constants are balanced, and expressed concern that it seems impossibly improbable that a single universe could have been formed with so perfect a set of randomly determined parameters. If our universe is just one of an infinite number of universes that are all different, then — like the roll of six sixes in Yahtzee — our random creation was a rare, but not impossible, event.
However, we still don’t have a theory to explain the origins of the universe. What set this bubbling set of scalar fields into motion? What created our universe’s wave function? Physics continues to find new ways to avoid the question of origins, but it just can’t find a way to answer it.
The controversy surrounding life on other planets currently involves one rock from Mars that spent many years lying in the middle of Antarctica. A full discussion is beyond the scope of this course and I would like to encourage you to explore discussions on these Web sites to learn more:
What is nanobacteria?
The Martian Meteor — Proof of life
Little Green Men?
Life on other worlds might exist, but is it the archetypal “little green man” or something beyond our understanding?
We don’t know the origins of our universe. Do we know our own origins? Not really. If we understood how we came into existence, we might better determine the likelihood of life existing elsewhere.
Ever since man was evicted from his place in the center of the universe, the universe has felt like a much more empty and lonely place. Philosophers looking skyward see the vastness of the cosmos as a terrible “waste of space” (to quote the movie Contact) if we are alone. Mathematically inclined optimists, looking for little green persons with whom we can share the stars, argue that it seems impossible for man to be alone when there are billions of stars in billions of galaxies, any of which could have evolved its own life forms.
The problem is, what exactly is life? Clouds of interstellar gas and dust contain amino acids — the molecules that make up DNA — and although scientists have been unable to create self-replicating cells in laboratories, the universe managed to do it once. And what the universe can do once, it usually does many different times in many slightly different ways.
Slight — and highly controversial — evidence exists for nanobacteria on Mars (see the sidebar). Nanobacteria are not exactly higher life forms, but just very, very small bacteria. Philosophically, the question is not so much whether there is bacterial life on other worlds, but whether there is other intelligent life in the universe. More to the point, is there intelligent life in the universe that we can detect and with whom we will be able to communicate?
It is not entirely clear that a handful of microbes need to evolve into multicelled life forms. An ameba, floating lazily through a pond, eating and drinking as it goes, is a perfectly adjusted life form. Single-celled life forms have remained unchanged over the millennia of the Earth’s existence. Why nature felt the need to build plants, dinosaurs, and eventually gum-chewing homo sapiens is a mystery.
Even if advanced, multicellular life does evolve on other worlds, how do we know that we could recognize it? Blue whales have the largest brains of any mammal. They have a complex language, live in communities, and nurture their young. Not all human beings exhibit all three of these characteristics. At this time, we have no way to judge the intelligence of blue whales, but there are some who would say that whales are as advanced as we are.
If extraterrestrial life is similar to our Earth’s sea mammals, we might never be able to communicate with any ETs we find. It is easy to imagine life taking on even more unrecognizable forms. So what do we do? The men and women who work with Search for Extraterrestrial Intelligence (SETI) gamble that life around foreign stars will be similar to terrestrial life in two ways. It will utilize radio waves for communication and/or entertainment, and it will communicate with frequency modulations similar to those of human radio signals. The use of radio frequencies is important because we can detect radio signals from distant sources. The rate of frequency modulation is important because if the frequency changes too slowly we won’t recognize the change and if it changes too quickly we won’t be able to detect the change.
So we should be able to detect extraterrestrial life — if that life has radio-like technology that has the same frequency modulation as terrestrial equipment.
The problem is, we have no reason to believe that life on Earth could have developed any faster than it did. We have had radio technology for only about 100 years and we have been obnoxious with our radio emissions for only part of that time. Radio waves travel at the speed of light. This means that another world trying to find the Earth from space would have to be within 100 light years to detect the Earth’s first, weak, early signals. For us to detect life on another world, it would have had to create radio equipment long enough ago that their signals have had time to reach us.
The existence of intelligent, detectable life involves a lot of “ifs.” If single-celled life exists, did it evolve into something with intelligence? If intelligence exists, is it intelligence that we can recognize or is it something so different that communication is impossible? If recognizable intelligence exists, has it invented radio communications? If other civilizations possess radio technology, are they close enough and old enough that we can detect their signals? Science can help formulate the questions, but it cannot tell us that life doesn’t exist and a null answer is impossible to prove. We can only say, after enough years of searching have passed, that intelligent life is most likely exceedingly rare.
One of the fundamental problems with answering the question, “Is there a God?” is stipulating what a god might be. To ancient men and women, we, with our portable computers and pyrotechnics, might well appear as gods. In this section, when I speak of God, I am referring to an all-powerful being. This discussion is not limited to the Judeo-Christian God, although this God is included in my description.
The Case for God
Is there an intelligence behind the quantum fluctuation that led to our universe? Or did everything arise from random chance?
The picture is bleak. We don’t know what (or Who) created the universe(s),and we have no reason to believe that we float alone among the stars. In a perfect world, I would enter into this final page of the final lesson with a message of hope and profound knowledge. Instead, I offer for your consideration the most fundamental question of all: the question of God. I’m going to start this section by presenting the atheist’s perspective and then turn to the deist’s view.
Our universe comes from apparent chaos. Both the varied pattern of large and small irregularities in the CMB and the distribution of stars of varied color across the sky are random — and the inflationary theories of Linde have our universe bubbling out of a chaotic mesh of scalar fields. If there is a God, argue some atheists, why do all things seem to have been born out of chaos and random noise? Even our evolution appears to be nothing more than a set of beneficial mutations.
The deist can counter that there is design in everything and that what appears to be random might simply be a complex pattern beyond our mortal ability to perceive. Christian theologian Ravi Zacharias puts the argument this way: If you look at a computer you see an object with purpose and careful design. To say that a computer could be created without a designer is to say that you can take all the parts of a computer, place them in a box and shake, and with enough shaking get out your gigahertz-speed Pentium 4. This is possible, just as it is possible that a monkey banging on a keyboard might type out the complete script of Romeo and Juliet. Unfortunately, just because something is possible doesn’t mean that it actually happens.
So we find the atheists claiming that because chaos lies at the roots, there is no God pulling patterns out of anarchy. At the same time, and from the same evidence, the deists find God in the designs in nature. It seems that cosmology can’t offer any definite answer to the question of God.
Ferris postulates an alternative. We stand looking back at a past that has no cause. What if God were that cause and created a universe that had its own creative future? What if God created a system that would lead to creatures with their own free will? A self-sustaining system, like a sealed terrarium, would grow and thrive and change in ways that aren’t completely predictable. This kind of universe would preserve human free will and would provide the first cause that lies beyond cosmology. This is a philosophical notion — one that cannot be understood within the scope of science or tested outside the human heart.
At this time, it is perhaps best if I refer you to courses in philosophy and religion. In this set of eight lessons we have explored our universe from the earliest moments in which the four forces were united to the far-distant future in which the universe will either continue to expand forever or collapse back on itself, repeating the big bang in reverse. We have examined the complexity of creating a planet capable of sustaining life and learned to look gratefully to Jupiter and our Moon for their protection. We have even looked into the smallest particles and deepest vacuums looking for the explanations for dark matter and dark energy.
Cosmology is not an easy subject and I hope that you have enjoyed our exploration. If you enjoyed this book for its historical content, I would encourage you to also read Coming of Age in the Milky Way, also by Timothy Ferris. If you are interested in learning more about the big bang, you’ll find a good background in Steven Weinberg’s The First Three Minutes. You can find discussions about particle physics and string theory in The Elegant Universe by Brian Green.
- Copyright 1997-2002 Barnesandnoble.com llc
Assignment: The Philosopher Within
Finish reading The Whole Shebang: A State-of-the-Universe(s) Report by Timothy Ferris. Just as many people strive to keep church and state apart, others try to keep religion and science apart. Do you think it is possible for a scientist, locked in his laboratory, to grapple with the concepts of origins without being biased by his culture and his personal religious beliefs? Many of our leading scientists have had strong religious backgrounds. Do you think that religion in general is a help or a hindrance to the scientist wrestling with the question of origins?