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100 of 113 people found the following review helpful:
2.0 out of 5 stars
The universe is a quantum computer that is computing itself., September 15, 2006
Great ideas lead to short papers in peer-reviewed journals. Often, the more prestigious the journal (Science, Nature), the shorter is the paper because of space constraints. Not so good ideas, on the other hand, lead to rambling books. The author is well published and certainly knows this. The premise here is that the universe is a quantum computer. Okay. What is it computing? Seth Lloyd asserts that it is computing itself. From here on the argument becomes circular. The universe is what it is because it is doing what it is doing. Computation is defined in a general way as essentially any kind of atomic change in state. Therefore, interactions (between particles) become synonymous with computation. The problem here is that when you equate something that clearly exists (the universe) with something which in fact really does not (a quantum computer is hypothetical, you cannot go out and buy one) you define the latter in terms most favorable to yourself. So, since an atom flipping states is equivalent to flipping bits, the physical world performs computation. Since the physical world follows quantum laws, it must be a quantum computer. At some point the whole thing becomes an issue of semantics.
The section on quantum computing could have been interesting. That quantum computers would potentially be very powerful we know. That they can simultaneously work on multiple questions is also clear enough. That so far they have done no more than factor the number 15 we might infer from the absence of any publicity. Lloyd points out that they should be able to factor a 400 digit number with ease. While I understand that they would do this by working on multiple problems simultaneously, what I am curious to know is how we would extract the desired answer (i.e. the 200 digit numbers that ARE factors) from all the other answers (i.e. the far more numerous numbers that are NOT factors) from this quantum computer. I am sure there is an answer, but where it matters the author is strangely silent.
In buying this book I naively assumed that computation is a well-defined process that conforms to certain principles. If the universe computes, it must do certain things, but not others. This might be expected to impose new constraints on the behavior of the universe and allow us to make predictions about where it is going and learn where it has been. Unfortunately, computation, as used here, is nothing of the sort. Any interaction becomes a computation and the universe is under no new constraints. It is simply doing what we already know it is doing and the theory gives us nothing new. It is simply another way of looking at the same thing. The underlying thesis could have been stated in a few pages and hardly seems to merit an entire book.
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63 of 80 people found the following review helpful:
4.0 out of 5 stars
Computer Scientist Offers a New Paradigm of the Universe, April 2, 2006
In Programming the Universe, Seth Lloyd, Professor of Mechanical Engineering at MIT and the designer of the first feasible quantum computer, presents an arresting new paradigm of the cosmos: The universe itself is a giant quantum computer.
Lloyd's hypothesis is that all physical systems register and process information. Life, language, human beings, society, culture--all owe their existence to the intrinsic ability of matter and energy to process information. When systems evolve dynamically in time, asserts Lloyd, they transform and process that information.
"The goal of this book," the author writes, "is to reveal the fundamental role that information plays in the universe. . . . By understanding how the universe computes, we can understand why it is complex."
A critic for Publishers Weekly writes, "[Lloyd's] hypothesis bears important implications for the red-hot evolution-versus-intelligent design debate." It comes as no great surprise that Lloyd, a scientist, comes down on the side of evolution.
"The conventional picture of the universe in terms of physics," writes Lloyd, "is based on the paradigm of the universe of a machine. Contemporary physics is based on the mechanistic paradigm, in which the world is analyzed in terms of its underlying mechanisms; in fact, the mechanistic paradigm is the basis for all of modern science. . . . The primary quantity of interest in the mechanistic paradigm is energy."
In his famous equation, E=mc2, Albert Einstein asserted the fundamental equivalence of matter and energy. But the universe, Lloyd asserts, is more than matter/energy: "This book advocates a new paradigm, an extension of the powerful mechanistic paradigm. I suggest thinking about the world not simply as a machine, but as a machine that processes information. In this paradigm, there are two primary quantities, energy and information, standing on an equal footing and playing off each other."
As a giant quantum computer, the universe possesses the same information processing power as a universal quantum computer, and this quantum-computational power of the universe provides a direct explanation for its intricacy, diversity, and complexity.
What then are the implications of Lloyd's hypothesis for "the red-hot evolution-versus-intelligent design debate"? Lloyd argues that the complexity of the universe evolved from the "simple universe" of the Big Bang, which occurred some 14 billion years ago. How, then, does one explain the universe's present complexity?
Asserting that complexity arose out of simplicity, Lloyd argues that the "intelligent design" (complexity) of the universe is not the work of an Intelligent Designer but is a result of the evolution of the universe itself. The giant quantum computer operates according to the natural principles of physics and then develops and processes its own information.
According to Lloyd, there is no "ghost in the machine," no Intelligent Mind or Spirit that designed the universe. On the contrary, the evolution of the universe occurred according to the actions, interactions, and reactions of its various physical components (atoms, electrons, protons, neurons, photons, quarks, and other subatomic particles). These physical (and chemical and biological)developments were (and are) spurred on to new complex combinations by entropy, gravity, and quantum fluctuations in the fabric of space/time.
The universe is not "a random collocation of atoms"; although one must not ignore Heisenberg's "uncertainty principle," the atoms and subatomic particles largely "behave" according to the universe's internally generated program. There is a duality in the universe, but it is not the duality of Mind vs. matter; it is the duality characteristic of the quantum nature of matter. For example, photons mysteriously behave both as particles and as waves.
"The medieval philosopher William of Occam," writes Lloyd, "was interested in finding the simplest explanation for observed phenomena. Pluralitas non est ponenda sin necessitate, he declared: 'Plurality should not be posited without necessity.' Occam urged us to accept simple explanations for phenomena over complex ones."
Employing Occam's razor, Lloyd rejects the metaphysical (mystical, spiritualistic, and supernatural) claims of Creationists and advocates of so-called intelligent design. The modified mechanistic model of the universe that Lloyd champions is non-theistic, natural, secular, and humanistic.
In some places, Programming the Universe is difficult to understand. Computer gurus and physicists will be better equipped to follow Lloyd's arguments. The main points of his hypothesis, however, are clear, and he often lightens the text with humorous quips and amusing anecdotes.
Roy E. Perry of Nolensville (rperry1778@aol.com) is an advertising copywriter at a Nashville publishing house. He is an amateur philosopher, Civil War buff, lover of classical music, avid chess player, and aficionado of fine literature.
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42 of 54 people found the following review helpful:
5.0 out of 5 stars
A most interesting and helpful way of viewing the Universe as processing information, April 5, 2006
Basically, there are two kinds of books on science for the general reader. The first and awful kind is written to make the mysteries of science a kind of Gee Whiz experience. The problem is that the explanations are so poor and misleading that the reader is actually further from a proper understanding of what modern science is about than they were before they read the book. The second kind is written by someone who not only has a profound insight into the topic they are sharing with the reader, they also have a special ability for stating things clearly and for making them less mysterious. This very interesting book is of the second kind and I recommend it to anyone who wants to think more clearly about quantum mechanics. Not the fake and misleading kind of popular fiction and the entertainment media, but of the kind that will actually help you understand the fabric of our universe.
While I am no scientist, and I cannot pretend to be able to explain everything in this book to you, I do feel that I have read the best explanations of the two-slit single electron interference pattern demonstration and the concepts of entanglement and decoherence. Seth Lloyd does a fine job of keeping these things understandable for those of us who are interested but clearly lack the proper background to delve into this stuff as he does.
This book would be superb for intelligent young people who are demonstrating a talent for science and engineering. I suspect that this book will results in stimulating a number of brilliant young minds to fine scientific careers. Possibly a few of them will work their way to becoming students of Dr. Lloyd at MIT. I am sure that this will be one of the positive outcomes of this strangely cool book.
I must admit that as I read through the book there was more than one time where my head was swimming, but the author makes his case well and the last two chapters pull everything together in a strong way that invite the reader to further study of this topic. The basic idea of the book is that, and realize that I am likely getting this wrong, as the energy created during the inflationary period of the big bang cooled and precipitated into matter, there was free energy (the stuff we use for "work" and that does things) and entropy. Entropy is a knottier problem than the casual observer might think. Dr. Lloyd says that a portion of entropy is really information. It is the universe processing and describing itself. The author demonstrates this to us in a step-by-step way that provides the reader with at least a sense of understanding. Dr. Lloyd does say at one point that if you don't experience dizziness when thinking about quantum mechanics you aren't trying hard enough (or words to this effect).
Dr. Lloyd demonstrates much of this to us through the notion of quantum computing (designing the first feasible quantum computer is one of the author's accomplishments) and how information is created and processed at the atomic level by manipulating quantum structures through the notion of manipulating qubits.
This is an extension of the mechanistic view of the Universe that has been so popular in physics and engineering for the past few centuries and it should help young people, who think so easily in the language of bits and processing, to build strong intuitions about the quantum reality. These intuitions will allow them to go further and faster than those of us who formed our ideas in the classical model of things. Simply because we find the probabilistic view of matter counterintuitive does limit us, whereas a young person who grows up learning about reality as a probability event will find grasping the realities of quantum mechanics almost natural. This is the real service this book can provide young people and those of us with more antiquated notions of things.
Strongly recommended.
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