Paul Davies

Paul Charles William Davies, AM (born 22 April 1946) is an English physicist, writer and broadcaster, a professor at Arizona State University as well as the Director of BEYOND: Center for Fundamental Concepts in Science. His research interests are in the fields of cosmology, quantum field theory, and astrobiology.

Paul Davies, September 2006

Quotes

Space and Time in the Modern Universe (1977)

• In the emerging picture of mankind in the universe, the future (if it exists) will surely entail discoveries about space and time which will open up whole new perspectives in the relationship between mankind, mind, and the uni-verse.… But what is now? There is no such thing in physics;it is not even clear that ‘now’ could ever be described, let alone explained, in terms of physics.… Notions such as ‘the past,’ ‘the present’ and ‘the future’ seem to be more linguistic than physical.… There is no universal now, but only a personal one—a ‘here and now.’ This strongly suggests that we look to the mind, rather than to the physical world, as the origin of the division of time into past, present, and future.…There is none of this in physics.… No physical experiment has ever been performed to detect the passage of time. As soon as the objective world of reality is considered, the passage of time disappears like a ghost into the night.
  • Page 222, Cambridge University Press, ISBN 9780521291514.

Other Worlds: A Portrait of Nature in Rebellion, Space, Superspace, and the Quantum Universe (1980)

• Science, it is usually believed, helps us to build a picture of objective reality – the world 'out there'. With the advent of the quantum theory, that very reality appears to have crumbled, to be replaced by something so revolutionary and bizarre that its consequences have not yet been properly faced.
  • 'Prologue', p. 12

The Accidental Universe (1982)

• All this prompts the question of why, from the infinite rage of possible values that Nature could have selected for the fundamental constants, and from the infinite variety of initial conditions that could have characterized the primeval universe, the actual values and conditions conspire to produce the particular range of special features that we observe. For clearly the universe is a very special place: exceedingly uniform on a large scale, yet not so precisely uniform that galaxies could not form; extremely low entropy per proton, and hence cool enough for chemistry to happen; almost zero cosmic propulsion and an expansion rate tuned to that energy content to unbelievable accuracy; values for the strengths of its forces that permit nuclei to exist, yet do not burn up all the cosmic hydrogen, and many more apparent accidents of fortune.
  • p. 111

God and the New Physics (1983)

• The brain is the medium of expression of the human mind. Similarly the entire physical universe would be the medium of expression of the mind of a natural God.
  • Ch. 17: 'The physicist's conception of nature', p. 223

The Cosmic Blueprint: New Discoveries In Nature's Creative Ability To Order Universe (1988)

• That the universe has organized its own self-awareness – is for me powerful evidence that there is 'something going on' behind it all. The impression of design is overwhelming. Science may explain all the processes whereby the universe evolves its own destiny, but that still leaves room for there to be a meaning behind existence.
  • Ch. 14: 'Is There a Blueprint?', p. 203

The Matter Myth: Towards 21st-century Science (1991)

• Matter as such has been demoted from its central role, to be replaced by concepts such as organization, complexity and information.
  • Ch. 1: 'The Death of Materialism', p. 9

The Mind of God: The Scientific Basis for a Rational World (1992)

• The scientific quest is a journey into the unknown.
  • Ch. 1: 'Reason and Belief', p. 21

• What is remarkable is that human beings are actually able to carry out this code-breaking operation, that the human mind has the necessary intellectual equipment for us to "unlock the secrets of nature"...
  • Ch. 6: 'The Mathematical Secret', p. 148

• Human beings have always been struck by the complex harmony and intricate organization of the physical world. The march of the heavenly bodies across the sky, the rhythms of the seasons, the pattern of a snowflake, the myriads of living creatures so well adapted to their environment – all these things seem too well arranged to be a mindless accident.
  • Ch. 8: 'Designer Universe', p. 194

• I cannot believe that our existence in this universe is a mere quirk of fate, an accident of history, an incidental blip in the great cosmic drama. Our involvement is too intimate.
  • Ch. 9: 'The Mystery at the End of the Universe', p. 232

The Fifth Miracle: The Search for the Origin and Meaning of Life (1999)

• In each and every one of us lies a message. It is inscribed in an ancient code, its beginnings lost in the mists of time. Decrypted, the message contains instructions on how to make a human being. Nobody wrote the message; nobody invented the code. They came into existence spontaneously. Their designer was Mother Nature herself, working only within the scope of her immutable laws and capitalizing on the vagaries of chance.The message isn't written in ink or type, but in atoms, strung together in an elaborately arranged sequence to form DNA, short for deoxyribonucleic acid. It is the most extraordinary molecule on Earth.
  • Ch. 1: 'The Meaning of Life', p. 41

• The laws of nature are rigged not only in favor of complexity, or just in favor of life, but also in favor of mind. To put it dramatically, it implies that mind is written into the laws of nature in a fundamental way.
  • Ch. 10: 'A Bio-Friendly Universe?', p. 271

The Eerie Silence: Renewing Our Search for Alien Intelligence (2010)

• To a physicist like me, life looks to be little short of magic: all those dumb molecules conspiring to achieve such clever things!
  • Ch. 2: 'Life: Freak Side-Show or Cosmic Imperative?', p. 31

The Demon in the Machine (Sep. 7, 2019)

6th International FQXi Conference, "Mind Matters: Intelligence and Agency in the Physical World." A source.

• The thing that separates life from non-life is information.

• Seventy-five years ago Erwin Schrödinger published... What Is Life?... the key point... was whether life can be explained by physics. ...Schrödinger ...said "We must be prepared to find a new kind of physical law prevailing..."

• [W]e... need some new physics. ...The attempt to square the circle by starting out with known physics at the atomic level and somehow life emerging at some higher level... I... don't think we're going to be able to do it without new physics.

• [M]ax Delbrück... expressed it... (to encapsulate)... [A]t the level of atoms it's just known physics, but at the level of the living cell it's some sort of magic.
  • Quote from Max Delbrück, "Life: The Magic Puzzle Box" (Dec. 1949) Transactions of the Connecticut Academy of Arts and Sciences, Vol. 38. pp. 173-190, was left out of this entry.

• We lack any sort of device that can... detect life. We don't have a life meter. ...We don't have a general purpose life meter that can detect life as we don't know it.

• The fundamental problem about trying to define life... If you go to a physics department... you'll be given a definition in terms of matter... force... energy... entropy... free energy, molecular binding affinities, and so on. If you go to a biology department... you'll be given a very different narrative in terms of... instructions, transcription, gene editing, translation, coding, signals...

• [B]iologists... define life in terms of its informational qualities... physicists tend to define life in terms of the physical qualities.

• [I]nformation pervades biology. Your DNA is chock full of encrypted information, and the encryption is really important. But genes don't act in isolation. They couple together to form networks, sometimes of great complexity, and information swirls around these networks. It can be stored.... processed... and it can have knock-on effects... beyond individual cells. Even bacteria can signal each other chemically... electrically and mechanically, and so, through physical forces, can exchange information and engage in cooperative behavior, like in biofilms.

• [A]nts... have... collective decision-making... a labyrinth of [network] information exchange... which can profoundly affect the outcome of the colony. We see it... in bird flocking.

• Perhaps the most exquisite example of information in biology... During embryogenesis there's the most meticulous choreography of organized information, so all the right bits end up in the right place, at the right time. ...[T]he power of information to sculpt [living] physical forms.

• [T]hat great information processing system between our ears... probably ...the grandest example we know of... in the universe.

• This web of information extends beyond individual organisms and communities of organisms to a planetary scale. ...Andrew Kim and Harrison Smith... looked at over 28,000 genomes and... produced this... plot of information being organized on a... planetary scale. ...[T]he biosphere was the original World Wide Web.
  • More at biorxiv.org) Universal scaling across biochemical networks on Earth, Hyunju Kim, Harrison B. Smith...

• Paul Nurse ...in his visionary essay ..."Life, Logic and Information" extols the virtues of thinking in an information, web-based way about life, and how, instead of worrying... about... the molecular level, we should think of life as being a collection of logic modules... with information flowing between them... control systems... [an] engineering approach.

• [W]ith the physics of living matter, have we joined... the world of physics with the world of informational biology?

• [I]nformation... has been in physics for a long time, in the most obvious way with Maxwell's demon... It was... just a Gedanken-Experiment... in 1867, but just in recent years, engineers (nanotechnologists) have built real Maxwell demons, and this is now something of a cottage industry.

• [T]he demon... is transferring heat from a colder region to a warmer region in apparent defiance of the second law of thermodynamics. ...[A] refrigerator... costs energy to run... but the demon is operating using information instead... The demon... runs without any energy expenditure.

• So in effect, information serves as a fuel, and this leads to the whole concept of information engines. Engines that will run on information power...

• Life was onto this... billions of years ago. Life uses many many nano-molecules... in effect, Maxwell demons. Our bodies are full of [them]... doing the business of life. ...not quite perfect ...but they're coming pretty close to the theoretical limit, in terms of energy expenditure.

• Voltage-gated ion channels are the way in which... you are thinking and paying attention, because the signals that travel between neurons, down the axons, are controlled by the flow of ions across the membranes of the axons... [T]hey are, in effect, little demons that sense the incoming signal and open and close the gates; and the ions flow. ...[T]his is so incredibly energy efficient that ...your brain, which is like a megawatt supercomputer, operates with the energy equivalent of a small light bulb.

• It's now commonplace to have an informational term entering into the fundamental laws of physics as a source of free energy.

• Information in life... amounts to much more than just playing the margins of the second law of thermodynamics, and gaining some... energy advantage. ...I'm calling this a demonic cut. It's much more than just Shannon bits at the thermodynamic level. Biological information is... contextual, or functional, or semantic. It depends upon the overall system.
  • Note: "Information that is... semantic, contextual, global, functional... demons with agency^attitude"

• [A] gene is a set of instructions for ribosome to make a protein. If you look at the DNA sequence that codes for a gene, there's nothing that can tell you, at the sequence level, that if you look at a particular nucleotide, that this is a bit of functional or coding or contextual information, and it's not just junk.

• [T]his is something that can't be defined locally. It's got to be defined globally, in the context of the system as a whole. ...[T]hat's a very difficult thing for physicists to cope with because we're used to formulating all our laws of physics as local laws, and not as global laws.

• I'm using this term demonic cut by analogy with the Cartesian cut...
  • Note: Cartesian cut metaphorically alludes to René Descartes' distinction between res cogitans (non-material, mental or thinking substance) and res extensa (corporeal or extended substance).

• [A]t what point does information, in the physics of matter, cease to just be a thermodynamic issue, and become much more of a control issue? ...[O]ne place ...is the genetic code. ...[H]ow did this come into existence?

• If ever you want an example of going from physics to biology, it's the origin of the genetic code.

• [T]here is... not just [some] new physical law, but a new kind of physical law. ...[W]hat kind of physical law? ...[O]ne idea that Sarah Walker and I have flirted with is state-dependent laws of information. ...[T]ake chess as an analogy ...If you had a modified game of chess in which the rules ...could be updated according to the state of play ...this opens the way to new forms of complexity and new forms of configuration.

• We want to know the transition zone between this demonic cut... from just [Shannon] bits of information... to this more complex form of global, or contextual, or functional information. ...[H]azarding some guesses ...it might be a transition that would be measured by the integrated information, or... pathway complexity that Lee Cronin toyed with, or the breakdown of unitarity, if you think that this is associated in some way with the quantum classical transition.

• [C]osmological limits of agency... [W]hat's the best that the universe can do? There's about... 10¹⁰⁰k bits of free energy out there. What could be achieved? ... [Egyptian pyramids have] been achieved... Maybe... astro-engineering... [T]ake a galaxy that's rotating clockwise and make it rotate anti-clockwise? ...I suspect ...maybe yes. ...[T]urn the expanding universe into a contracting universe? ...I'm sure the answer is no.

• I know of no theorem that tells you... the maximum amount of change that agency can achieve in the universe, and what interests me... is agency at the end of the universe. If you end up in De Sitter space, which has a temperature and a horizon entropy, can you do anything with... those thermal fluctuations? Can you mine them... to extract energy?

• [P]article detectors in De Sitter space respond as if they are immersed in a bath of thermal radiation. However, the stress energy momentum tensor in De Sitter space is not that of thermal radiation. It's just a renormalization of the cosmological constant. So there's something a bit funny about the thermal nature of De Sitter space, and I've been interested in whether you can mine that thermal stuff...

• [I]f you have a Maxwell demon or something like a Szilard engine in De Sitter space, could you use it, as Maxwell envisaged, to use information to extract energy from De Sitter space and... do... useful work? ...[Perhaps] only if you can create a region of the De Sitter space that is screened out from that horizon... from that thermal nature. If you put a reflective barrier around the demon, you then have De Sitter space, but with the horizon screened out. ...[T]hat's a problem I'm working on now ...

External links

• Paul Davies at Arizona State University