130 of 147 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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30 of 34 people found the following review helpful:
1.0 out of 5 stars
Authorial vanity trumps expertise, October 9, 2009
This review is from: Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos (Paperback)
I've always admired the notion (first promulgated by Voltaire?) that the true measure of intelligence is the ability to simultaneously comprehend two mutually contradictory ideas. So I tend to take a mellow approach to ideas that I disagree with. However, this book angered me, not because of its ideas, but because of its serious flaws.
The first serious flaw is that the author cannot keep his ego from seeping into the text. He regales us with triumphant tales of how he confounded his students with deep questions and then nobly revealed the true answers. Sheesh, man, why use the dialog approach using weaklings as your interlocutors? Pit yourself against somebody who can do more than behave as your straight man. Argue with yourself, if you have to! But presenting yourself as the all-knowing professor rubbed my fur the wrong way.
The problem of author vanity permeates the entire book. At no point does the author admit to uncertainty, or present two sides of a case, or even admit that anything he writes is controversial. One gets the strong impression that everything is crystal clear to this author. That impression raises my hackles.
The overwhelming self-assurance of the author explodes in his face when he gets it wrong. In the section "Exorcising Maxwell's Demon" in Chapter 4, he writes:
"The full exorcism of the demon was not accomplished until recently. (I played some part in this ceremony myself.)"
Perhaps Mr. Lloyd is older than I imagine. The exorcism of Maxwell's Demon was accomplished by Leon Brilloun, the physicist who patented the atomic bomb, in a paper published in 1951. Mr. Brilloun does not mention any contribution by Mr. Lloyd. It would appear that Mr. Lloyd is unaware of Mr. Brilloun's paper. Worse, his explanation of the exorcism of Maxwell's Demon is a turgid mess that makes no sense at all. Between claiming credit for another man's achievement and botching the explanation of Maxwell's Demon, I reached the limit of my tolerance. I literally threw the book away from me at that point.
Perhaps the material after Chapter 4 redeems the book; I do not know, because I did not read it.
The other serious flaw in the book is its smarmy vagueness. In attempting to avoid the intimidating reliance on mathematical and technical definitions, Mr. Lloyd resorts to poetic phrasings. These would be acceptable if they weren't so damned cute -- and if they made sense. For example, in attempting to make clear the difference between energy and information he writes, "Energy makes physical systems do things. Information tells them what to do." At first glance, that seems a pithy observation. But go back and read it again; what is the author really saying? Does energy give molecules speed, and information give them direction? Does the energy in an A-bomb make the bang and information tells it what to destroy?
I was disconcerted by the author's fuzziness regarding information. He never defined it -- which is not necessarily a fatal flaw, given that a book for the educated public should not burden its readers with undue technical detail. But he used the term in such a myriad of ways that I started to think that he was using it to refer to any magically powerful force. Information, in this book, seems capable of performing wondrous feats.
Physics is finally coming to terms with the concept of information as a physical concept. The change began after World War II and has been edging forward for fifty years; in the last ten years, progress has accelerated. A clearer concept of information and its relationship to the physical universe is emerging. Mr. Lloyd misses one of the most important factors in this process: that information itself is inextricably bound with the concept of time, in something like the way that mass and energy are bound together, only more complex. It is not information that is the fundamental quantity; it is information flow, or bandwidth.
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76 of 97 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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