Customer Reviews

Fabric Of Reality

5 star:		(37)
4 star:		(13)
3 star:		(12)
2 star:		(6)
1 star:		(35)

 

 

I really cannot find any redeeming value in this book. I had hoped to find some insights from a world famous quantum physicist, and a founder of Quantum Computation, however what I received was a hodge-podge of loosely related themes, the only connection I could find was "Physics is the most important thing in the multiverse, and quantum physics is even more important."

Some of the outlandish claims that Deutsch makes in this book are the following: the mind-body problem is solved; P=NP is solved (it's false); the Church-Turing Thesis is a fact; everything that Deutsch dislikes is a form of solipsism. Of course, no details are given to the solutions, as these are just trivial facts, I guess, according to Deutsch.

But after reading the book, probably the one claim that I abhorred the most was never explicitly stated, but a simple corrollary are statements that he makes again and again: every human endeavour is just quantum physics. The reason for this is because human beings are (at the base level) just quantum-mechanical things, everything we do is a result of physics, and therefore while mathematicians (I happen to be a PhD student in mathematics, set-theory in particular) may think that they are dealing with abstract concepts, they are actually dealing with nothing more that quantum effects in their brains (which Deutsch equates with minds). A simple extension of this principle tells us that philosophy is just a quantum-mechanical process, ditto with art, politics, friendships, love, etc.

Of course, something that is hidden in the above idea is a reductionist claim --- that everything can be reduced to quantum effects. Not surprisingly, it turns out that Deutsch thinks that reductionism is wrong. There are several places in the text where Deutsch ends up contradicting himself, or appeals to claims that he thinks are incorrect. (He grants that criticism of scientific theories does not rest on experimental evidence alone, but while claiming that in fact experimental evidence is very low on the scale, for the most part the only criticisms he ends up making are through experimental evidence.)

My advice for anyone interested in the metaphysical or epistemological issues raised in this book --- read the works of a meta-physicist, not a quantum-physicist.

Hello!

I actually slogged my way all the way through this EXCEPTIONALLY BADLY written book, because of my large interest in the subject matter. David Deutsch should have used a ghost writer for this, as he obviously was not up to the task. He is in love with page long paragraphs, as this book is filled with them. This, of course, reduces readability and comprehension. He couldn't write a clearly written sentence, if his life depended on it.

He also (out of 3,000+ books I have read) is the most arrogant writer I have ever read. He dismisses, cavalierly, and without much explanation, ANYONE who doesn't agree with him, and, though not saying this directly, certainly hinting strongly that he thinks that anyone disagreeing with him is an idiot. I found this attitude repulsive.

I expected to see a lot of experimental research to be quoted in this book, but it is almost totally lacking in any. He wanders around in this book, in bizarre philosophical mumbo-jumbo, that I don't think that he really understands properly, acting as if this proves some cosmic points.

The few facts that he actually provides in this book, are better described in any number of other books. If I had not read previously on related topics, his writing is so bad, that this book would have been incomprehensible to me.

To sum up in a much clearer way, than Deutsch could ever manage, the main point of his book, he basically says that a finite (but very large), number of parallel universes exist, that cover everything that every could, or might have happened; and that this in essence, happened at the moment of the big bang, or within 10 to the -43 seconds after. Time is discrete, not continuous (like a string of pearls looks continuous, but if you break the thread, it is actually shown to be discrete).

Time doesn't "flow", but our conciousnesses are only aware of one discrete moment of time, at a time. (Think, motion picture here. There are 30 static, non-moving picture frames per second, but your mind "fuses" them, into an apparent continuous whole, of an illusion of motion. This is how Deutsch views the universe. ALL the "movies" (universes), that can, could, or might, ever exist; and all possible events of "time", were created simultaneously at the moment of the big bang. Our conciousness, though, is only aware of one, discrete, "movie frame" (discrete bit of time), at a time, within only one "movie" (universe). So, continuous time DOESN'T really exist. It just appears that way because of limitations in our conciousness. Another way to think of it, is that the multiverse is like a video tape store. Each video tape, represents a different universe. Each static frame on the video tape, represents a discrete moment of time. Though all video tapes (universes), and all static frames (discrete moments of time), exist simultaneously, your consciousness can only derive meaning from it, from experiencing the frames sequencially, NOT simultaneously. So, only discret time exists, not continuous time.)

There, now you don't have to bother buying this book. Since he gives almost NO experimental evidence for this point of view, anyway, you don't need to worry about the fact that I didn't offer "proof", either!

For those people whose reviews I read, that seem to think that this book was a stunning revelation; I can only conclude that you haven't read much about this topic, before. Stuff along these lines, existed in science fiction probably since the thirties, and in hard science, for decades.

Whether or not some of what Deutsch believes, is ultimately proven to be correct or not, I don't know. For people in the field pushing parallel universes, though, it might have been better if this book had never been written, as it was such a HUGE turn-off for me.

My 2 cents worth.

Karl

I found this book to be extremely hard to follow as it was more of a fluffed up marshmellow than actually fact or theory based. What I found much easier to follow was one by M. R. Franks titled The Universe and Multiple Reality.

As I am very interested in all modern theories, I have read several books trying to go deep into the Quantum Theory. Up till this one, none had satisfied me.
To be able to explain a difficult subject, and Quantum Theory is a very difficult one, one needs to really understand it and David Deutsch really knows what he is talking about!
Unhappily, most of the well known scientists know and believe little about what they talk.
Read this book, follow David explanations step by step, and you will arrive into places and conclusions your mind never thought possible they exist.
The book takes you into unsuspected areas, and opens fantastic horizons to your mind!
A mandatory book to any one that is trying to understand the world in which we live, as well as all the other possible worlds!

In the spectrum of quantum interpretations the parallel universe version has a beguiling science fiction charm, but seems to suffer the same fate as the intimations of 'platonic ideas': they seem to be there, but what is 'existence'? Til mathematicians decide, rogue physics can define no boundary to its abstractions and we find this phantom of the multiverse tricking us into borderline reality. Out in left field then, we suspect.
A very interesting book, which outstripped my competence, but which also struck me in another way, due to its fond wish for the higher coherence of physics, evolution, epistemology, and computation, taken into some unity.
I am often baffled by a genuine puzzle, why so many brilliant physicists can't see the flaws in Darwin's theory. This book unwittingly shows the reason, the projected 'consilience' of subjects, the ambition to complete the foundations for a Total World View, veil the transition of brilliant physics to Darwinian muddle, in the name of reductionism. It doesn't add up, and the wished for plug in unit in the ascent on complexity needs more than Dawkins' genetic 'evolutionary particle'. From genius to idiot.

The funny thing is the brilliant intuition of parallel worlds, however that is to be taken. For we see in historical evolution a mysterious parallel effect, in the so-called 'Axial Age', as historical evolution branches into a synchronous phase. So maybe all this is onto something.
The big puzzle: why are all the world's best physicists confused about Darwinism?

I read this once about 5 years ago. It was a vertigo-inducing experience. The author's writing context-switched between way too many subjects to do justice to any of them. On many topics, the author's reach clearly exceeded his grasp; and certainly, he fails to communication just exactly how all of these supposedly complementary theories interlock into a coherent, multifaceted whole. Despite all this, I found the book very enjoyable. What really caught my attention was his highly conversant treatment of Popperian philosophy of science. Many scientists and mathematicians are unaware of some of the weirder turns taken by 20th century philosophers of science (analytic not to mention continental). The author does a good job of refuting what still today is the prevailing view of epistemology. Where he errs is in his categorical claim that knowledge obtained by "Popperian" selection & criticism is justified (in the philosophical sense of the word). Popper never, ever would have claimed this for his theory. What Popper did was to propose a way out of the the Wittgensteinian cul-de-sac of all-or-nothing knowledge. Readers interested in this subject would do well to check out "Evolutionary Epistemology" Radnitzky & Bartley, ed.

I would love to see many-worlds shown superior to all available alternatives, but this book did not make the case.

The chapter on epistemology is excellent. He concludes that a successful theory must have explanatory power and must satisfy evidence that refutes all prior theories. He does a good but incomplete job of illustrating the explanatory power of many-worlds, failing to show how many-worlds explains the EPR results. Unfortunately he ignores all competent existing theories.

Indeterminism and wavefunction collapse are not required by QM. They are merely interpretations. Wavefunction collapse in particular is not required to explain the double-slit results because the virtual particles (another interpretation) that constitute the wavefunction are not observable and have no relation to the new entity that results from a "measurement" interaction. The EPR experiments assert that "hidden variables" havc been eliminated, but indeterminacy is still not proven. Deutsch rightfully proclaims many-worlds superior to one interpretation of QM, based solely on the double-slit results, but he fails to mention alternatives.

The most compelling evidence is the idea that a quantum computer could make computations requiring >10^500 parallel universes. IF such a computation is performed, it may be difficult to explain in any other way, but it has not been done and the obstacles may be fundamental.

He asserts that all worlds in the multiverse must follow the same physical laws. There are many more worlds out there that fit in his philosophy. We know our particular laws result from post-Big-Bang broken symmetries and that event itself was not a pristine Perfect Form. What does Deutsch mean by "laws of physics"? Is his interpretation that there are many multiverses?

I had great hopes for the chapter on time, but his writing style is sometimes impenetrable and it came across as hand-waving.

If Richard Feynman liked many-worlds, it must be right. Deutsch should try again, in collaboration with a scientifically literate writer.

I have read this book twice, which says more about me than the book. Where can one start! Although the audacity is breathtaking, the assumptions are stupefying.

I keep going back to his early chapter on the slit experiment (which Feynman said was the essence of quantum mechanics) and wonder why Deutsch skips through it so quickly.
It is the bedrock of his theory of multiple universes, but rather than discuss the obvious objections, he moves on to philosophical conjectures rather than physics. Can he show solutions to the wave equations that support his conclusions? How about experiments that could settle the issue? He does not say!

Given the current state of cosmology how can one object to any theory, whether it be VSL, a multiverse, or some concept from a yet to be resolved string or super-string theory? But, my god, how can Deutsch just lay this stuff out as if it is incontrovertible?

The book starts out breathtaking but ends up exhausting and annoying.

This is a thoroughly brilliant book. The criticisms of it aren't worth bothering with; it's meant to be speculative and out-on-a-limb, that's what gets people thinking in an inert and conformist era like the one we are in now. It's worth pointing out that Einstein's paper on the Photoelectric Effect was almost not accepted for publication by Max Planck at Annalen der Physik in 1905; Einstein had to call it a "heuristic" theory to even get it considered. So look at The Fabric of Reality as heuristic.

David Deutch's 'Fabric of Reality' marks the triumphant return of Natural Philosophy. The central aim of this book is to present the structure of our best theories (evolution, [Quantum] computer science and epistemology) in a way that clearly relates them to our understanding of reality, and then show how these structures are inextricably intertwined. I believe he is remarkably successful and displays a thorough understanding of the subject matter outside of his 'native' QM as those subjects relate to his 'Theory of Everything'. Speaking of which, he is also the first (that I know of) to come anywhere close to understanding what this TOE really IS (and will become). That is, our TOE is now, and at any point in the future or past, the core intertwining of these theoretical strucures he so elegantly exposes.

In order to appreciate this book, it is neccessary to understand the angle Deutch takes on the undertanding of science and the growth of knowledge. And this requires a bit of historical context.

In the early 20th century, the two infant sciences of quantum mechanics and computation theory had no observed connections. In turn, the counter-intuitive results of the quantum theory (as revealed over the next 100 years) led to a loss of confidence in our ability to understand reality (as expoused by such buzzwords as 'uncertainty'). This intellectual climate led many of our best scientists to ignore the importance of taking our best theories seriously. Instrumentalism and positivism flourished. Explaination and understanding where not considered fundamentally important. Everything was arbitrary and only utility mattered (in the sense that accurate prediction was thought to be the only useful thing to do with a theory). Consequently, it was not understood how knowledge grew, as understanding itself was seen as unimportant!

If any of Deutsch's four theoretical 'strands' could be called the seed of Deutch's synthesis, it would be Popper's epistemology. For it is this explainatory structure that provides the 'structure for the structure' that Deutch then fits the remaining strands into. Essentially, Popperian epistemology says that knowledge grows only through the process of trial and error, conjecture and refutation, not by some inductive process. And the key to formulating a conjecture that will survive the refutation process is understanding the explainatory structures of our best theories as they relate to the problem's domain. The creation of new knowledge requires the human capacities of innovation and creativity, specifically the mysterious weaving process whereby similarities between seemingly disparate phenomenon are spontaneously seen. This is how Deutch weaves an accurate (though tenative) description of reality. More importantly, this is how Deutch's reality says it must be [self consistency]. If Deustch's theory itself is true, then, it constitutes a growth of knowledge. The theory itself describes how this can happen.

I would guess that Deutch had his first glimpse of the woven threads when he figured out that computation theory, once thought to be purely an abstract construct, had to have a physical basis in reality. After all, computers are physical objects, subject to the laws of physics. Alan Turing's classical computation theory had many incompatibilities with classical physics that kept it in the realm of abstractions, but we now know classical phyics is false. This physical basis for computation turned out to have its roots in our newest, most fundamental (reductively speaking) physical theory, quantum mechanics. Combine this with the role of computation in evolution (genes 'rendering' environments), along with the role of our senses in representing our environment to our brains (virtual reality), and the growth of knowledge (rendering ideas) and you can see how computational processes are fundamental to Deutch's reality.

Deutch's contribtions to science and philosophy probably won't be appreciated until we have working, practical quantum computers. Only then, when his theories are what allow us to build our working technology will he be taken seriously. 'Fabric of Reality' provides us then with a prescient glimpse of what will eventually become our world view, describing the first great unification of our best theories.