Paul Davies - The Demon in the Machine: How Hidden Webs of Information Are Finally Solving the Mystery of Life

Paul Davies

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THE DEMON IN THE MACHINE

How hidden webs of information are solving the mystery of life

The curiosity remains to grasp more clearly how the same matter, which in physics and in chemistry displays orderly and reproducible and relatively simple properties, arranges itself in the most astounding fashions as soon as it is drawn into the orbit of the living organism. The closer one looks at these performances of matter in living organisms the more impressive the show becomes. The meanest living cell becomes a magic puzzle box full of elaborate and changing molecules

Max Delbrck

There are many books about what life does. This is a book about what life is. Im fascinated by what makes organisms tick, what enables living matter to do such astounding things things beyond the reach of non-living matter. Where does the difference come from? Even a humble bacterium accomplishes things so amazing, so dazzling, that no human engineer can match it. Life looks like magic, its secrets cloaked by a shroud of impenetrable complexity. Huge advances in biology over the past decades have served only to deepen the mystery. What gives living things that enigmatic oomph that sets them apart from other physical systems as remarkable and special? And where did all this specialness come from in the first place?

Thats a lot of questions big questions too. Ive been preoccupied with them for much of my working life. Im not a biologist, Im a physicist and cosmologist, so my approach to tackling big questions is to dodge most of the technicalities and home in on the basic principles. And thats what I do in this book. Ive tried to focus on the puzzles and concepts that really matter in an attempt to answer the burning question: what is life? I am by no means the first physicist to ask it; I take as my starting point a series of famous lectures entitled What is Life? by the great quantum physicist Erwin Schrdinger, delivered three generations ago, addressing a question that Darwin dodged. However, I think we are now on the threshold of answering Schrdingers question, and the answer will usher in a whole new era of science.

The huge gulf that separates physics and biology the realm of atoms and molecules from that of living organisms is unbridgeable without fundamentally new concepts. Living organisms have goals and purposes the product of billions of years of evolution whereas atoms and molecules just blindly follow physical laws. Yet somehow the one has to come out of the other. Although the need to reconceptualize life as a physical phenomenon is widely acknowledged in the scientific community, scientists frequently downplay how challenging a full understanding of the nature and origin of life has proved to be.

The search for a missing link that can join non-life and life in a unitary framework has led to an entirely new scientific field at the interface of biology, physics, computing and mathematics. It is a field ripe with promise not only for finally explaining life but in opening the way to applications that will transform nanotechnology and lead to sweeping advances in medicine. The unifying concept that underlies this transformation is information, not in its prosaic everyday sense but as an abstract quantity which, like energy, has the ability to animate matter. Patterns of information flow can literally take on a life of their own, surging through cells, swirling around brains and networking across ecosystems and societies, displaying their own systematic dynamics. It is from this rich and complex ferment of information that the concept of agency emerges, with its links to consciousness, free will and other vexing puzzles. It is here, in the way living systems arrange information into organized patterns, that the distinctive order of life emerges from the chaos of the molecular realm.

Scientists are just beginning to understand the power of information as a cause that can actually make a difference in the world. Very recently, laws that interweave information, energy, heat and work have been applied to living organisms, from the level of DNA, through cellular mechanisms, up to neuroscience and social organization, extending even to a planetary scale. Looking through the lens of information theory, the picture of life that emerges is very far from the traditional account of biology, which emphasizes anatomy and physiology.

Many people have helped me in assembling the contents of this book. A lot of the ideas I present here originate with my colleague Sara Walker, Deputy Director of the Beyond Center for Fundamental Concepts in Science, who has greatly influenced my thinking over the past five years. Sara shares my enthusiasm for seeking a grand unified theory of physics and biology organized around the concept of information. Life is the next great frontier of physics! she declares. I have also benefited greatly from discussions with the students and postdocs in our group at Arizona State University (ASU). Special mention must go to Alyssa Adams, Hyunju Kim and Cole Matthis. Among my many brilliant colleagues at ASU, Athena Aktipis, Ariel Anbar, Manfred Laubichler, Stuart Lindsay, Michael Lynch, Carlo Maley, Timothea Newman (now at the University of Dundee) and Ted Pavlic have been especially helpful. Farther afield, I greatly value my many conversations over several years with Christoph Adami at Michigan State University, Gregory Chaitin of the Federal University of Rio de Janeiro, James Crutchfield at the University of California Davis, Andrew Briggs at the University of Oxford, David Chalmers at New York University, Lee Cronin at Glasgow University, Max Tegmark at MIT, Steven Benner at the Foundation for Applied Molecular Evolution, Michael Berry at Bristol University, George Ellis at the University of Cape Town, Piet Hut at the Earth Life Sciences Institute in Tokyo and the Institute for Advanced Study in Princeton, Stuart Kauffman of the Institute of Systems Biology, Charles Lineweaver at the Australian National University, who playfully disagrees with almost everything I say and write, and Christopher McKay at NASA Ames.

Also in Australia, Derek Abbott at the University of Adelaide has clarified several aspects of the physics of life for me, and John Mattick, the visionary director of the Garvan Institute in Sydney, has taught me that genetics and microbiology are not done deals. Paul Griffiths at the University of Sydney has provided me with deep insights into the nature of evolution and epigenetics, while Mikhail Prokopenko and Joe Lizier at the same university have shaped my thinking about network theory and provided some critical feedback. Johnjoe McFadden and Jim Al-Khalili at the University of Surrey, Birgitta Whaley at the University of California, Berkeley, and science writer Philip Ball provided valuable feedback on . Peter Hoffmann of Wayne State University kindly clarified some subtleties about ratchets. Giulio Tononi of the University of Wisconsin, Madison, and his colleagues Larissa Albantakis, and Erik Hoel, now at Columbia University, patiently tried to de-convolve my muddled thinking about integrated information. The Santa Fe Institute has also been a source of inspiration: David Krakauer and David Wolpert have dazzled me with their erudition. Michael Levin at Tufts University is a very valued collaborator and one of the most adventurous biologists I know. I also profited from some lively exchanges with computer engineer and business consultant Perry Marshall.