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The End of Certainty

New physics for 21st century, Aoû 13 2003

The greater part of the book is written in a natural style, but some sections are highly mathematical even for the majority of scientists! This mathematical presentation has a curious explaining. There are several version of Prigogine's theory, but the first versions had been "abandoned", and then Prigogine details the new approach: "Star-unitary theory for LPS outside of Hilbert space".

An earlier reviewer said that the book provides a solution to three of the most important problems in science: (1) Time's arrow. (2) The measurement problem in QM. (3) The existence of freewill. Precisely, I am working in those and other questions, and I do not believe that claim was completely correct (and perhaps Prigogine believed the same, because in his last communication, said me "The questions that you ask are very difficult."). In my opinion, the novel theory is conflictive both in mathematical and physical details, but I consider that, at least, the aim of the School is correct one. Irreversibility and uncertainty are two fundamental features of our universe. I see that orthodox physics (including particle physics and the so-called String-M theory) is incorrect and/or inapplicable. I believe that, whereas other "popular" books (The Quark and The Jaguar, The Elegant Universe, etc.) should be "relics" in 21st century physics, Prigogine's book will be then a basic work.

The contributions of Prigogine's physics to the understanding in other disciplines, as chemistry, are not clear. In fact, I believe that the impact of recent Prigogine's ideas into fundamental chemistry has been "insignificant", because his revolutionaries ideas in physics are an outcome of their previous chemical investigations (Nobel Prize for Chemistry). For example, in his complex spectral theory, energy is an imaginary quantity, and this is in direct conflict with standard quantum theory postulates. However, in theoretical chemistry, one always defines a transition state by means of an imaginary frequency. As said Prigogine in a recent Solvay conference, "all of Chemistry deals with irreversible processes". I cannot say the same of physics.

The book is very good one, but I disagree in one point. When one writes a scientific paper for publication in a specialized journal (as Physical Review), one can write about everything. Referees and other scientist can either accept or reject your work in scientific grounds. When one writes a popular book for non-expertises, one must be the most "neutral" possible. If this is not possible, one must to "alert" to the reader. This book is not neutral and, in some restricted sense, shows several theories and ideas as been of broad acceptance or current use in science. Of course, this overemphasizes the scientific status of the so-called Brussels School and minimizes the importance of other interesting points of view. In my opinion, this is not a correct attitude. For example, the "diagrammatic" method developed by Brussels School in the 60's (and illustrated in the book) is broadly not used by scientific community. See, for example, "Nonequilibrium Statistical Mechanics" by Robert Zwanzig for a view in more standard formalisms. In addition, I also must say that some previous Prigogine's ideas in dissipative structures, kinetic potentials, etc. are not standard, and other, as the "universal" criterion of evolution (following production of entropy), was experimentally shown to be false. Of course, other contributions of called Brussels School are simply impressive, for example the extension of scattering theory of particle physics to more general situations of chemical kinetics. Effectively, you have read fine, orthodox S-matrix of "fundamental" physics can be derived as an idealized asymptotic version valid for typical accelerator experiments! I am sorry, but I must said that Chemistry is not applied QED.

Conclusion: The book describes an excellent philosophical view in a "new" physics, and for this reason it may be a central piece on your collection. Nevertheless, I consider that the scientific way proposed is a little conflictive and some mathematics may be modified!

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Tightening the Science Net Meshes. But Still Missing Much!, Mars 5 2002

Par	Julio C. S. Barros "juliocbsiqueira@terra.com.br" (Rio de Janeiro, Rio de Janeiro Brazil) - Voir tous mes commentaires

This book will very likely prove readable by most general readers, like myself, provided the technical parts are carefully skipped, and the central ideas are correctly spotted. It truly presents essential insights to issues like: the emergence of complexity; self-organization; the nature of matter; determinism vs probability; and the validity of time symmetry in both quantum mechanics and classical mechanics equations. As to issues like the actual existance of a flow and arrow (direction) of time (which, by the way, is the very subject of the book) and the existence of free will, the book may be too far from conclusive...

It seemed to me (only top experts could really tell for sure) that Prigogine showed compelling evidence supporting the idea that, contrary to the prevailing notions in the field of physics, there is time asymmetry both in quantum mechanics and in classical mechanics. And also, that reality at both these levels is not deterministic, but truly probabilistic. He further showed that determinism should be replaced by a probabilistic account of events both in situations where we have finite knowledge about the initial conditions and in situations where we have infinite knowledge (we are done with Laplace's Demon at last!). This alone is already a breakthrough, even though probably not news to well-informed members of the physical sciences community.

I found Prigogine a little bit contradictory (it might be that Nature itself is contradictory in this regard) when talking about determinism/time-reversibility. Sometimes, I got the impression that it only exists in idealized (non-real) situations, and sometimes I understood it as if it does exist in certain specific (real) situations.

I also found his rejection of Gödel's time-reversible interpretation of Einstein's equations far too emotional, instead of being based on experimental-mathematical grounds. As far as I know, this viewpoint, too, has experienced considerable growth over the last 10 years or so (the studies about CTC - closed timelike curves), and it seems to be a quite respectable field of inquiry. Time-flow reversibility does not seem less crazy to me than the fact that we have to use imaginary numbers (that is, numbers that do not exist at all!) in theories that deal with some very basic properties and behaviors of matter, like quantum mechanics and chaos.

Even though physicists usually equal time symmetry (in physical equations) to time-flow reversibility, and asymmetry to irreversibility, I don't see why this has to be so. Nor does this book clarifies this issue any further to the layman (it is interesting to point out in this regard that even the probabilistic collapse of the wave function is considered by the prevailing views of physicists to be symmetrical/reversible, according to Penrose in The Empreror's New Mind). Our suspicions and complaints about the mysterious nature of time are very much justified: space gives us 3 dimensions, bidirectional and with no compulsory flow. Time, on the other hand, gives us just 1 dimension, unidirectional and with compulsory flow. At best, we can slow it down, by traveling close to the speed of light (quite comforting, isn't it?).Time alone is responsible for most of our losses in life (unless you get exiled or something...). I think that, interpreting "time symmetry" as "time reversibility", scientists have actually tried to solve the unsolvable.

In our quest to understand the Universe, we often find three kinds of questions: first, those that can be proved or disproved, like the old statements "The Sun revolves around the Earth" (disproved), and "The Moon revolves around the Earth" (proved). Second, questions that can be proved, but not disproved, like the existance of God or of life after death. Third, questions that cannot be either proved or disproved, like the existance of consciousness in other human beings than ourselves (or in dogs) and (to me) the actual existance of time flow.

Prigogine says that in this book he tried to follow (or discover?) a "narrow path" between utter determinism and total randomicity, probably hoping to find room for free will in between. Although I think he did a brilliant work, I feel that he got stuck in this Narrow Path. His work refutes determinism, but instead of presenting phenomena or advancing mechanisms to support free will, it only casts us into the depths of utter chance. In spite of that, when talking about self-organization in dissipative structures, Prigogine passes on the idea of "choice", even saying (more than once) that "matter begins to see" and that "the system chooses". This might ascribe to nature at its most basic structure the properties of "life" and maybe even of "consciousness", which might mean that we are at the verge of a revigorated return to the ancient ideas of hilozoism and panpsychism. Furthermore, this blurs the limits between emergence and reductionism, for it is very difficult to take a sound reductionist stand (or emergencionist stand) if we don't know what to expect of the world around us (we can't tell if something is emerging or just "arising").

Prigogine's appeal for sanity is both his virtue and his weakness, in a Universe that pays little heed to human's logic and causality. A Universe in which, regardless of being dictated by an authoritarian God or determined by blind and cold laws of nature, the only theory that may account for all that there is is the familiar and provincial B.I.S.O. theory. Namely: Because I Say So!

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