|A Tear at the Edge of Creation
Copyright © 2010 by Marcelo Gleiser
Barring the existence of other self-aware beings capable of theorizing about life and death, weimperfect accidents of creationare how the Universe thinks about itself. To my mind, this is a life-transforming revelation, the substance of this book. Even though we live in no special place in the cosmos and play no starring role in the grand scheme of things, the fact that we carry this banneralone or notdoes make us very special. For this very reason, we must be extra careful. In spite of all our achievements, we will do well to remember that our story is just our story, imperfect and limited as we are; we will do well to remember not to go after absolute truth but after understanding. [...]
Wonderful as it is, science is a human construction, a narrative we create to make sense of the world around us. The truths that we obtain, such as Newtons universal law of gravitation or Einsteins special theory of relativity, are indeed impressive, but always of limited validity. There is always more to explain beyond the reach of a theory. New scientific revolutions are going to happen. Worldviews will shift. Yet, vain as we are, we place too much weight on our achievements. Our successes have led us to believe that these partial truths are scattered pieces of a single puzzle, the components of a Final Truth, waiting to be discovered. Great minds of the distant and recent past have devoted decades of their lives in search of this Holy Grail, Natures hidden code [...] Knowingly or unknowingly, they are heirs to a philosophical tradition rooted in ancient Greece that links perfection and beauty with truth. Over the centuries, this tradition was fused with monotheistic belief: Gods creation was perfect and beautiful. To understand it, to search for immortal truth, became the highest of aspirations.
For millennia, we have lived under the mythic spell of the One. Kneeling at our temples or searching for the mathematical mind of God, we have yearned for a connection with what is beyond the merely human; we have dreamt of an abstract perfection that we could not find in our lives. In doing so, we closed our eyes to ourselves, refusing to accept the fragility of our existence. It is now time to move one. It is now time to shake free of the old imperative for perfection and embrace the lessons of a new scientific worldview that explores the creative power of Natures imperfections and accepts that there are limits to knowledge.
The journey will be humbling, as we face the smallness of our existence in a vast, indifferent cosmos. And yet, small that we are, our very existence makes us unique. Thinking aggregates of inanimate atoms, we are rare and precious. [...] The decisions we make now will shape our future and that of our planet. It is time to understand that preserving life is what really matters.
Belief springs from our helplessness in dealing with things we cannot control, predict, or understand. If we are nothing more than flesh and blood, a mere assembly of molecules subject to the laws of Nature, then we have no choice but to follow the course of material things and die, disintegrating into dust. How much more wonderful it is to believe in the afterlife, in nonmaterial entities capable of bypassing the rigid limitations imposed by materialistic reasoning! If science is to help us, in the words of the late Carl Sagan, as a candle in the dark, it will have to be seen in a new light. The first step in this direction is to admit that science has its limitations, as do the scientists who do it. [...] We should, of course, share the joy of discovery and the importance of doubt. Perhaps more importantly, as I argue in this book, we should explain that there are faith-based myths running deep in sciences canon and that scientists, even the great ones, may confuse their expectations of reality with reality itself.
|Keplers blindness was his blessing. He constructed a model of the world with the data he had available. At any given time, including ours, this is the best that anyone can do. What we can measure will always limit our view of reality. Keplers mistake was to give his vision of reality a finality it didnt deserve. Glimpsing the hidden code of Nature proved so cathartic that he was bewitched and took his belief for the truth. Keplers mistake was to forget that a final theory is impossible because we will never know all of reality.|
The Asymmetry of Time
The Imperfection of Electromagnetism
|If electric monopoles are so common, why not magnetic ones? How could the two fields be considered truly unified if such obvious disparity between them persists?|
The Birth of Atoms
Think of it as a love triangle: electrons and protons, with opposite electric charges, are trying desperately to get close and bond, but needy radiation constantly interrupts them by kicking the electrons away. With time, though, radiation gets weaker and unable to avoid the inevitable. It finally departs, leaving protons and electrons to consummate their electric affair. This epoch marks a boundary: before it, no atoms existed, only particles and radiation. After it, the cosmos was filled with atoms and radiation. This radiation, no longer colliding with electrons, cruises freely across space, responding only to the occasional gravitational attraction of large gatherings of matter. [...] When Arno Penzias and Robert Wilson detected it in 1965, the Big Bang got the boost it needed. With its main prediction confirmed, it became more than speculative theory.
The Jitterbug Cosmos
As we move toward the beginning, the shrinking of space forces us to consider how quantum physics will affect the young Universe: loosely speaking, the cosmos had atomic dimensions. Herein lies the challenge; so far, we have not been able to construct a theory of gravity compatible with quantum mechanics. [...] Since in the world of the very small everything fluctuates, at short distances space and time will also fluctuate. Measurements of distances and of time intervals, which we take for granted, will become probabilities. Picturing space-time as a rubber sheet again, at the quantum level we would see oscillations that twist and contort it in myriad ways. Time runs amok. The consequences are mind-boggling. Without reliable measures of distance and time, or of how to interpret them probabilistically, the whole edifice of physics crumbles. The notion of a phenomenon as something that happens in space and time becomes meaningless.
Back to the Beginning
|Irrespective of how aesthetically attractive a theory is, the final deciding factor is always data. A simpler theory, initially considered correct, may be unable to explain new observations. [...] When searching for new theories, it is important to keep in mind that Ockhams razor is only a selection tool and should not be used to decide whether or not a given theory is correct. Nature has the final say: simpler is not always better. In the heat of invention it is easy to let aesthetic values function as choice criteria, confusing a beautiful or elegant idea with a correct one. Contrary to our aesthetic longings, beauty is not always truth.|
A Small Patch of Weirdness
|Since we dont know the details, all we can say at this point is that as inflation progresses the unstable scalar field converts itself and its energy into other particles: in a process similar to radioactive decay, where one particle morphs into two or more, the scalar field becomes other kinds of matter particles. Eventually, these initial decay products convert into more ordinary particles. According to this view, the primordial scalar field that drove inflation would be matters first common ancestor. This is not as strange as it seems. Particles decay and change into each other all the time. [...] According to current understanding, as inflation nears its end, the matter conversion process goes berserk. The scalar field explosively dumps its remaining energy into a maelstrom of particles, filling the cosmos with hot matter. In the modern view, it is this explosive creation of matter at the end of inflation that is associated with the Big Bang: in other words, the Big Bang is not the beginning. The details, however, remain nebulous.|
What we have learned this far is that we can solve most of the issues with the Big Bang model with hypothetical scalar fields whose origin remain a total mystery. [...] Perhaps the Universe is trying to tell us something about our dreams of a final theory. Perhaps we live in a cosmos much more mundane and imperfect that our expectations of sublime explanations and high symmetry make us believe. Perhaps all that is needed is a small patch of weirdness.
|What we do know is that dark energy makes up about 73 percent of the stuff in the cosmos. The rest is made up of dark matter (23 percent) and our humble protons and electrons (4 percent). The shocking revelation of modern cosmology is that the Universe is 96 percent unknown.|
In the same way that quantum indeterminacy will always limit our understanding of the world of atoms and particles, our limited knowledge of the physical world forbids the construction of a Theory of Everything. The very notion of such a theory is nonsense, as it presupposes that we know all there is to know and thus to unify. [...] Only our intellectual vanity precludes us from seeing this clearly and moving on. Science will not be diminished in its grandiose task of explaining Nature if it doesnt have a unified dream to pursue.
Even if superstring theories one day prove relevant to explain our Universe and do what they are set out to do, they will not be the final word. Our explanations of Nature are never finalthey only grow more effective at explaining increasingly accurate data. [...] Given the discoveries of the past few decades, we need only open our eyes to see that our narrative is headed in a novel direction: it is not that a special Universe produced special beings; it is that a mundane Universe produced special beings.
What we are learning at an ever-increasing rate is that there is no grand plan, no cosmic blueprint, no overarching explanation for our Universe. [...] The order that we assign to Nature is the order we seek in ourselves. The world is only beautiful because we think about it.
The Asymmetry of Matter
Symmetry and Beauty
|Symmetry is, and will remain, a key ingredient of our theories. [...] The problem starts when symmetry is taken too far and is enthroned as dogma. Symmetry is beautiful, but, apologies to John Keats, beauty is not necessarily truth. Or, for that matter, truth beauty.|
A More Intimate Look at Symmetry
One of the deepest consequences of symmetries of any kind is their relationship with conservation laws. Every symmetry in a physical system, be it balls rolling down planes, cars moving on roads, planets orbiting the Sun, a photon hitting an electron, or the expanding Universe, is related to a conserved quantity, a quantity that remains unchanged in the course of time. In particular, external (spatial and temporal) symmetries are related to the conservation of momentum and energy, respectively: the total energy and momentum of a system that is temporally and spatially symmetric remains unchanged.
The elementary particles of matter live in a reality very different from ours. The signature property of their world is change: particles can morph into one another, changing their identities. [...] One of the greatest triumphs of twentieth-century particle physics was the discovery of the rules dictating the many metamorphoses of matter particles and the symmetry principles behind them. One of its greatest surprises was the realization that some of the symmetries are violated and that these violations have very deep consequences.
Violation of a Beautiful Symmetry
|Even though matter and antimatter appear in equal footing on the equations describing relativistic particles, antimatter occurs only rarely. [...] Somehow, during its infancy, the cosmos selected matter over antimatter. This imperfection is the single most important factor dictating our existence.|
Back to the early cosmos: had there been an equal quantity of antimatter particles around, they would have annihilated the corresponding particles of matter and all that would be left would be lots of gamma-ray radiation and some leftover protons and antiprotons in equal amounts. Definitely not our Universe. The tiny initial excess of matter particles is enough to explain the overwhelming excess of matter over antimatter in todays Universe. The existence of mattter, the stuff we and everything else are made of, depends on a primordial imperfection, the matter-antimatter asymmetry.
Science of the Gaps
What we know of the world is surely not all there is to know. Any assertion to the contrary displays only human arrogance. Hence unifying all there iseven at the level of fundamental physicsis fated to fail. [...] The best that we can do is collect what we discover of the world in the most coherent possible way.
Unification: A Critique
|We have seen how the weak interactions violate a series of internal symmetries: charge conjugation, parity, and even the combination of the two. The consequences of these violations are deeply related to our existence: they set the arrow of time at the microscopic level, providing a viable mechanism to generate the excess of matter over antimatter. [...] The message from modern particle physics and cosmology is clear: we are the products of imperfections in Nature.|
|I saw that trees never fork perfectly, that clouds are never perfect spheres, and that stars are scattered in the skies without any apparent pattern. I realized that we were imposing order on Nature, an order we longed for ourselves. There are natural laws, and they reflect patterns of organized behavior. But are these laws blueprints of physical reality? Or are they logical descriptions that we create to represent it?|
|It is not symmetry and perfection that should be our guiding principle, as it has been for millennia. We dont have to look for the mind of God in Nature and try to express it through our equations. The science we create is just that, our creation. Wonderful as it is, it is always limited, it is always constrained by what we know of the world. [...] The notion that there is a well-defined hypermathematical structure that determines all there is in the cosmos is a Platonic delusion with no relationship to physical reality. Its an attempt to find God, even if metaphorically, through the lenses of science.|
The Asymmetry of Life
First Life: The Where Question
|Lifes powerful force took hold of my whole being. I experienced what to me was an entirely new dimension of the sacred, a deep sense of communion with life at a scale way beyond the human [...] Life worships at the shrine of Nature. Science, at least the way I see it, is one of the doors that lets you into the temple.|
The Asymmetry of Existence
Is the Universe Conscious?
What interests me here is that many people, in particular Unifiers and, of course, religious groups, interpret that view as a cop-out. Somehow, by accepting the accidental nature of physical and chemical processes that take place in Nature, we give up the search for deeper relationships among life, mind, and cosmos. [...]
The critics of this idea miss the fact that a meaningless cosmos that produced humans (and possibly other intelligences) will never be meaningless to them (or to the other intelligences). To exist in a purposeless Universe is even more meaningful than to exist as the result of some kind of mysterious cosmic plan. Why? Because it elevates the emergence of life and mind to a rare event, as opposed to a ubiquitous and premeditated one. For millennia, we believed that God (or gods) protected us from extinction, that we were chosen to be here and thus safe from ultimate destruction. [...] When science proposes that the cosmos has a sense of purpose wherein life is a premeditated outcome of natural events, a similar safety blanket mechanism is at play: if life fails here, it will succeed elsewhere. We dont really need to preserve it. To the contrary, I will argue that unless we accept our fragility and cosmic loneliness, we will never act to protect what we have.
|If there is a grand plan for the Universe and we emerge from it, then it follows that we shouldnt be special; similar conditions elsewhere should generate sentient beings. This view has been elevated to a principle known as the principle of mediocrity, an extension of the Copernican principle that states that Earth is an unexceptional planet and that we are just one out of a multitude of civilizations scattered throughout the universe. Given what we already know of the history of life on Earth and in the solar system (and some of the other stellar systems astronomers are now observing), it is very hard to agree that Earth is unexceptional, and even harder to believe that there are countless civilizations out there.|
|The laws of physics and the laws of chemistry as presently understood have nothing to say about the emergence of life. As Paul Davies remarked in Cosmic Jackpot, notions of a life principle suffer from being teleologic, explaining life as the end goal, a purposeful cosmic strategy. The human mind, of course, would be the crown jewel of such creative drive. Once again we are chosen ones, a dangerous proposal. [...] Arguments shifting the mind of God to the mind of the cosmos perpetuate our obsession with the notion of Oneness. Our existence need not be planned to be meaningful.|
Meaning and Awe
|Unified theories, life principles, and self-aware universes are all expressions of our need to find a connection between who we are and the world we live in. I do not question the extreme importance of understanding the connection between man and the cosmos. But I do question that it has to derive from unifying principles.|
Inherent in our drive to understand is a deep reverence for the beauty and drama of the natural world, the awe we experience at the grandeur of Creation. Contrary to what so many have believed for millennia, there is no a priori connection between this awe and the longing for the harmonies, the search for a final explanation for all there is. The awe that drives our search for meaning need not be attached to an antiquated notion that all is one. [...] To say that life is the creation of a purposeful cosmos is to promote it to a state of pseudoreligious immunity, independent of our actions and choices. That, to me, is a grave mistake, as it frees us from our responsibilities as the only living creatures (that we know of) mindful of lifes importance.
Beyond Symmetry and Unification
If all is reason and causation, if everything rests on rational explanations, what place for our human emotions, the pain of loss and despair, for our capacity to love?
Perhaps the greatest of all injustices of such an indictment against science is the notion that a naturalistas opposed to a supernaturalistdescription of existence is devoid of magic and wonder. [...]
Science is a way of knowing, of uncovering meaning. It is fed by the same sense of awe that inspires the piety of saints and the deeds of the enlightened [...] We dont need a divine purpose to justify our search for knowledge.
My point is that there is no Final Truth to be discovered, no grand plan behind creation. Science advances as new theories engulf or displace old ones. The growth is largely incremental, punctuated by unexpected, worldview-shattering discoveries about the workings of Nature. [...]
Once we understand that science is the creation of human minds and not the pursuit of some divine plan (even if metaphorically) we shift the focus of our search for knowledge from the metaphysical to the concrete.
Marilyn Monroes Mole and the Fallacy of a Cosmos Just Right for Life
For a clever fish, water is just right for it to swim in. Had it been too cold, it would freeze; too hot, it would boil. Surely the water temperature had to be just right for the fish to exist. Im very important. My existence cannot be an accident, the proud fish would conclude. Well, he is not very important. He is just a clever fish. The ocean temperature is not being controlled with the purpose of making it possible for it to exist. Quite the opposite: the fish is fragile. A sudden or gradual temperature swing would kill it, as any trout fisherman knows. We so crave for meaningful connections that we see them even when they are not there.
We are soulful creatures in a harsh cosmos. This, to me, is the essence of the human predicament. The gravest mistake we can make is to think that the cosmos has plans for us, that we are somehow special from a cosmic perspective.
Us and Them
Given that the laws of physics apply across the Universe and that the same chemical elements are found in other stellar systems, it follows that if we found primitive life in at least one other planet or moon in our cosmic neighborhood, we should indeed expect it to be widespread: the principle of mediocrity, at least as it relates to the existence of life, would gain support. The cosmos could indeed be biofriendly, and the possibility that there is a deep link between life and the cosmos would have to be taken seriously. [...]
Proof of a cosmic imperative for life would be a blow to the Darwinian orthodoxy that discounts any kind of determinism in life-related processes. [...] Yet we know that stars result from the gravitational contraction of clouds of hydrogen gas, a (fairly) well-understood physical process that, under the right conditions, is repeatable across space without any purposeful intentionality. In other words, even if primitive life were discovered elsewhere and we were to conclude that it was fairly common in the cosmos, we could keep the explanation for its existence well within scientific boundaries.
The situation would be quite different if alien life were multicellular.
A New Directive for Humanity
|We have longed for the harmonies for too long; we have longed for cosmic companionshipdivine or alienfor too long. We must accept that we are alone in the cosmos, if not in absolute termsas we can never be certain of what lies beyond our instrumentsat least in practice. This makes us very special indeed.|
|We are witnessing the greatest mass extinction since the demise of the dinosaurs 65 million years ago. The difference is that for the first time in history, humans, and not physical causes, are the perpetrators. [...] Life recovered from the previous five mass extinctions because the physical causes eventually ceased to act. Unless we understand what is happening and start acting toghether as a species we may end up carving the path toward our own destruction.|
|Epilogue||Garden of Delights|
We have a chance to change the course of things and salvage the world we grew up loving. Even if some have doubts as to how severe the upcoming storm will be, there will be a storm. The first raindrops are falling already.
We should not be gambling with our childrens future.
text checked (see note) Oct 2011