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93 of 104 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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10 of 10 people found the following review helpful:
2.0 out of 5 stars
It says quantum so it must be clever, March 25, 2008
The author says that the universe is a computer because it manipulates matter in an automatic, unthinking way - just like a computer.
But surely this is a circular argument? As the computer works by using the laws of physics, it is a truism to say that the laws of physics themselves constitute a computation. What does this statement actually tell us?
I was hoping that the book would put some flesh on the author's idea, but after reading it I'm still waiting.
At any point in the history of humanity, we have used our most sophisticated knowledge for explanatory purposes. When the most sophisticated machine was a clock, we described the universe as a clockwork machine. Now that the cleverest thing we know is quantum theory, we get books like this.
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62 of 79 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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