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Roger Penrose and the Road to Reality
Flipping through the eleven-hundred pages, you notice the gratuitous inclusion of mathematical formulae and the chapter titles on the page headers -- "Quantum algebra, geometry, and spin," "Gravity's role in quantum state reduction," "Calculus on manifolds" -- suggest a far more exclusive audience than yourself, a lowly paper-pusher with a four-year degree. "But then, what's this doing in the popular new releases?" you ask yourself, "Shouldn't it be hidden away in the darkened corner of the store's physics section?" But that's where you're wrong, you realize, glancing through the author's preface; this book is for you: Penrose has, it seems, composed a mathematical physics book for the general audience -- and not merely an introductory one, but one that takes you to the frontiers of modern theory.
The trouble with the common popular-science books that propose to illustrate modern physical theories is in their implicit premise of avoiding mathematical notation and concept in favor of plain English. This works to an extent, but ultimately breaks down when the nature of the subject matter itself is mathematical. Indeed, after reading the wonderful Dancing Wu Li Masters, the reader is no more prepared to plunge into a textbook on modern physics or to comprehend even the titles of the latest mathematical physics papers on Arxiv.org. Physicists know about the fundamental particles or the nature of space only through the mathematics that model the phenomena. Which is not to say that such English language renderings are useless, but they skillfully devise to distance themselves from what physicists actually do, as well as to reenforce readers' natural aversion to numbers and formulae.
Penrose's approach is not to dive head-first into the most strenuous material or to assume a proper background for the comprehension of advanced physics; instead, the first several chapters are devoted to building the necessary mathematical subtext for the remaining bulk of the book. The volume's length is not, as is often the case, a result of lengthy diversions or pedantry (needless complexity); Penrose keeps his eye on the ball throughout, consistently informing the reader how the topic at hand is related to the over-arching theme and infusing the more well-known pedagogy with creative insight, so that even a talented math major may learn from the introductory chapters on number systems or geometry. What's more, the careful organization of the disparate topics permits a fluid drift from one to the next. The effect is a single cohesive book and not a collection of notes or essays.
With 390 illustrations and a generous supply of endnotes and bibliography entries, it's clear that Penrose didn't consider the work completed with the text alone. The inclusion of short problems within the footnotes hints to the reader what concepts are important to understand. The usual footnote-commentary is withheld for the endnotes at the end of each chapter.
It's probable that the name "Roger Penrose" might excite some memories you may have of his previous works, published over a decade ago, both of which explore the mind-brain relationship. At least one of these (Shadows of the Mind -- the other is the more popular The Emperor's New Mind) proposes a quantum theoretical explanation for consciousness which was perhaps too liberal to have been taken seriously by neurologists. Penrose's efforts in quantum theory have, however, been more successful than those in neurology: in 1988 he was awarded the Wolf Prize, one of the very highest honors in mathematics (perhaps second only to the Fields Medal), along with Stephen Hawking, and has made invaluable contributions to quantum physics for the past several decades, proving himself to be one of the finest scientific minds of our day. In consequence to his stature, it's certainly a treat for laypeople that Penrose has donated the time and energy to the creation of a monumental expository work for general consumption.
Whereas the average pop-science journalist reaches upwards to accrue a book's material, Penrose's acknowledged expertise on the subject forces him back towards the ground again. If you think about it, I suppose this is as difficult a task, since much of what Penrose describes he's known for forty or fifty years (he was born in 1931). He apologizes in the final chapter for the necessity of handpicking among the dozen or so "theories of everything," sometimes according to his own professional biases. Today's leading theory, "String Theory" along with the theory of "Loop Quantum Gravity," and the little known "Twister Theory," are all covered in the later chapters; the first portion of the book builds the mathematical foundations for the succeeding chapters, which give an indepth treatment of quantum physics and quantum field theory. These topics are followed by the previously described "theories of everything."
A glance at the table of contents may make or break your purchasing decision; chances are, if you find the mysteries of the terms somehow galvanizing, then you'll enjoy the book. On the other hand, if the eclectic terms frighten you, you should perhaps look at the preface (where Penrose gives solace to anxious readers), or it may be best to avoid the book altogether.
As I mentioned earlier, little has been done for the general audience to explore the wide expanse between physics and mathematics. The Road to Reality is, in this respect, a virtually pioneering effort, and given its size, scope and quality, I would venture to guess it will remain the de facto text in its area for many decades to come, and may safely be placed on your bookshelf next to E.T. Bell's Men of Mathematics, Douglas Hofstadter's Gödel, Escher, Bach, or Benjamin Yandell's recent (*highly* recommended) The Honor's Class: Hilbert's Problem's and Their Solvers.
I am fortunate to have had some mathematics education and so am familiar with the basic principles of complex numbers, calculus, and geometry, making the first several chapters, while still insightful, less toilsome than it might've been. I suspect that the average bright high school graduate would have no trouble with Penrose's quick treatment of these concepts. I would recommend the reader have at least some familiarity with the basic terms of mathematics and physics (i.e. when Penrose mentions "set" you know he's referring to a particular mathematical structure) or the book could overwhelm you quickly. Additionally, readers would be at an advantage having read "English-based" modern physics books such as The Dancing Wu Li Masters, Michio Kaku's Hyperspace, Brian Greene's The Elegant Universe or a similar book about 20th century quantum physics. Either way, it's safe to say that despite the virtuosic readability of the text, it's still going to take an intellectual commitment on the part of the reader to reap all of the available knowledge."
You can purchase The Road to Reality: A Complete Guide to the Laws of the Universe from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Too often I see people reading these "physics for the general public" books that simplify so much they're almost misleading, and then the people who read them assume they're experts and walk away drastically mislead, repeating silly things like the idea that the schrodringer's cat metaphor is meant literally or string theory literally means there's all these dimensions right next to us. Unfortunately some of the things in modern physics-- like strings or quantum mechanics-- if you don't at least sort of understand the math, you don't understand it at all. It's nice to see someone at least attempting to do a "general public physics" book that actually tells it like it is rather than trying to give silly zen koans.
I just hope this book doesn't do anything like imply that there's any evidence whatsoever for the veracity of string theory.
...what's still used in university physics courses? Not most of the books mentioned by others. What is? Another extremely weighty tome (and those who've held it know it could be used to bludgeon Governor Arnold in one whack) called Geometrodynamics. I tossed it casually back on the shelf at Borders recently and nearly broke the shelf.
If it's a choice of someone giving me their POV based on their understanding of the math and having an encyclopaedia sized copy of the math which I can work with to get my own POV, well that's a matter of whether I'm overachieving and truly engrossed or looking for coffee table material in which case, sure, I'll look at this book.
But not one more thing by Kaku and those in that stripe. I'm tired of popular crap about "this is really how the universe works" and at the time of first printing it has already been contradicted by seven different Discover articles which themselves descend from thirty plus serious physics journals. A one page pamphlet would do that says, "We have no farking idea. We THINK it goes this way, but we don't really know. Here's a an artist's rendering and some fancy quotes. They've not been fact checked because there are no facts, only suppositions. You can get books with serious formulas at your local college bookstore."
If my grammar and spelling are off, I am [distracted/tired/careless] (take your pick)
I agree completely. I disagree with Penrose's conclusion, but reading the book made me admire him for several reasons:
-he's clearly smarter than I am. Not that remarkable, but we all run into idiots who have nothing to teach us every day. Reading the words of someone who has an unambiguously superior intelligence is not something that we do every day.
-he's generous with his talents. Like Carl Sagan, he's got an obvious love for what he studies, and he takes the time to write the books for anyone who wants to commit a little brain power to learn something new. Hey, thanks! I appreciate it.
-he understands how science is supposed to work. The Emperor's New Mind was the second book on the same subject. His first book ran into a lot of criticism, and so he wrote the second book taking that into account, to address the criticism. That's the mark of a real scientist like Penrose vs. a crank. A crank would have written the book, bristled at the criticism, and proceed to while like a little bitch about how the scientific "orthodoxy" rejects any new idea, because it threatens their little imbecilic closed minds and comfortable little lives in their ivory towers. Penrose shows us all how to be criticised: accept the criticism, learn from it, refine your theories, and try to persuade the critics again. Lather, rise, repeat. Penrose knows that he bears the burden of proof.
Read Penrose's books.
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
Worthless to whom? Certainly to a physicist such works are worthless, but the days of the polymath are long past. I read somewhere that Goethe is considered to be the last polymath who was thought to be in command of all and everything as it was understood in his time. Today we are in need of informed and adventurous popularizers who can at least attempt to bring the latests discoveries of science to the public. David Suzuki is an example.
"Academicians are more likely to share each other's toothbrush than each other's nomenclature."
Cohen
If you can't grok calculus, you are never (repeat: never) going to get 'the more advanced theories of physics'.
... yuk. And doing it was only half the battle - you had to know *when* to do it...
The ideas behind calculus aren't that hard to understand, but teaching them is a skill - most teachers I've seen tend to just explain the ideas then hope sufficient example problems will do their job for them. It's a lot easier if you learn to derive the basics (d/dx, integral around a path, partial differentials etc.) from first principles - it's not that you'll use the first-principles approach ever, but the understanding is worth the learning pain.
To give another datapoint on Physics' needs: I recall my first college term as a physics undergrad - we had a "basic primer" in maths (a 4 week course) which was essentially the 'A' level Further-Mathematics syllabus. Those unfortunates who hadn't done further-maths (about 50% of people) were a bit shell-shocked by the end of the primer course. Once that was out of the way, we got into the meaty stuff that you need for a Physics BSc. Most of us had to work damned hard to grok that - integrating partial differential tensors, residues, integral transforms
I guess the point I'm labouring to say is that some stuff is just complicated - irreduceably so. If you remove the complexity, you remove the understanding and therefore the whole point.
Simon
Physicists get Hadrons!
...the paperback version comes out in the UK this summer and this autumn (er, fall...) in the US.
I had second thoughts when I saw the hardback price; but I'll probably go for the paperback version.
"Slashdot - News and Chat Sites Deviant". (Click "homepage" link above for details).
Something to talk to your friends about is innumeracy. There's really no excuse for an educated person to be so terrible at math that they cannot balance a checkbook without a calculator. I had a friend in college that did not know how to "borrow". I was just flabbergasted. John Allen Paulos' book is a little dated, but still quite effective at convincing friends that they should maybe try a little harder. You also need to be engaging. I've explained the cardinality of infinite sets to "lay" people. It's very cool, and you can see it dawn in them that some "infinities" are bigger than others. Maybe I'll blog that. Hmm.
blarg.
Yes, he has Wolfram envy. Which is a shame, because it's not the size it's what you do with it that counts.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Mathematics pretty much is the language of Physics, unfortunately for many. Without it, you're pretty much limited to explaining concepts metaphorically through analogies to things from everyday life. You can't do that for very long without seriously misrepresenting what it is that you're trying to explain, and of course you'll never communicate any knowledge that can be successfully built upon that way.
Having taken a Phil of Mind course with Dennett, I can't say that he was unfair to Penrose. And Dennett isn't alone - try Colin McGinn, for example. The problem is that Penrose is a True Believer in free will: without free, unpredetermined human choices he believes that there is no autonomous self, so no consciousness, no responsibility. So he needs a source of indeterminacy to defeat the inexorable forces of determinism. The trouble is, quantum effects can't give you that kind of inteterminacy at the neuorological and mental level - if they did, all of the other emergent laws of matter and chemistry and biology would fall apart. Ordinary everyday physics relies on quantum effects being smoothed out statistically. You can't have it both ways - smoothed out at the atomic level and re-emerging at the neurological level (or even higher - shudder).
Maths is the art of finding what must be true within a system often expressed in liguistic form, but whereas a language is a local (though often approximately copied) utilitarian structure that binds meaning together; mathematics is a one-to-one mapping of a structure that is found to be the same by all practicing mathematicians (which is pretty close to objectivity if you ask me) onto an agreed linguistic form. When mathematicians use different symbols and reasoning, they still find the same things to be true as they find when they use the original set. That is: the linguistic element is arbitary to a high degree; it is not the important thing; rather: the underlying structure that exists before it is expressed symbolically is what is important.
If you believe maths to be, rather than having a language, you will not be a very competent mathematician, for you will be inclined to engage in symbolic manipulation as an arbitary and bizzare exercise without intuiting the underlying nature of mathematical truth.
When I say that maths can be viewed as being less than a language, I mean that the above-mentioned structure is highly restrictive. The potential of using mathematics for conveying "human meaning" (to do with day-to-day judgement and decision-making) is extremely poor. Insofar as mathematics is used to help in everyday matters, it does so by analysing a system that is intuited to have the right properties. Normal language and reasoning is then used to build an analogy with the phenomenon under consideration, but common language and understanding build the bridge, not mathematics.
Wikileaks, no DNS
I always find it fascinating how much is known about 'god', when there is so little proof that he exists (maybe like Santa Claus?). How do you know that a being with the order of intellegence of human^2/ant wouldn't be able to do things that you think only a being 'outside' of physics can do? What we are able to do certainly is not in any way something that an ant can conceptualize.
No, I don't trust in god. He'll have to pay up front, like everybody else.
You seem to imply that Powerpoint is some sort of advancement. I find it to be an impediment to information transfer, actually. I can always arrange the information using some other method which produces superior results (unless you like the car zooming audio effects and screen wipes...)
Take a look at this and then let me know if you think that powerpoint is really all that....
No, I don't trust in god. He'll have to pay up front, like everybody else.
The "quantum mind" idea was definitely the theme in his books of a decade or so ago, but this one is really more an argument for re-thinking the direction the majority of physicists seem to be going in trying to come up with a "theory of everything".
The "quantum mind" idea had, at its base, the concept of some new kind of physics that links quantum mechanics and general relativity together, in a way very different from the supersymmetry/string theory take of recent years: Penrose thinks gravity is more fundamental, and quantum mechanics really just an approximation. And he has some strong arguments in this book on why there is something fundamentally wrong with quantum mechanics - particularly the time-symmetry fundamental to the theory. Except for those messy reduction processes embodied in the Schrodinger cat, which few physicists other than Penrose treat as any sort of serious problem.
The other aspect of it is more a philosophical thing (though related to the Godel argument) that somehow our minds have a relationship with the platonic world of logic and mathematics that cannot be explained by ordinary physical processes. But this is book is a very serious one, and he doesn't get into that stuff at all.
Energy: time to change the picture.
Like most physicists, he suffers from the illusion that he knows everything about everything. His theories of intelligence and conciousness are so bad they are not even wrong.
As far as I can tell, his argument was "quantum physics is complicated. The brain is complicated. Therefore it can only be explained as quantum physics".
You know, I'd be very, very surprised, if not stunned, if the brain didn't rely on quantum effects.
/being there/, the effects of quantum mechanics have to be used (if not worked around) by nature in it's construction of living matter.
I'd actually go so far as to say that my entire worldview, as pertaining to biology and it's application of physics/chemistry, would crumble.
All 'inventions' are based off physical principles. In many instances these are taken from the existing biological world, and if they are not, it is soon found out that nature has something similar already. And it's getting so that more and more inventions which are at the forefront of their field take direct notes from nature (extra-hard and light metal layers based on clamshells, spider silk, gecko's feet, use of nano-particles).
And let's face it: nature has been playing around a lot longer than us with the laws of physics. By it's very nature of
So if the brain uses 'quantum mechanical rules' (like it uses osmosis and other physical tricks), it would mean that the brain is a quantum computer.
-- Waht? Tehr's a preveiw buottn?
My biggest problem with Penrose's "consciousness stems from quantum uncertainty" theory is that it makes no sense from an evolutionary biology point of view. Nearly all of molecular biology is about using protein machinery to provide repeatability and the minimization of quantum uncertainty including, as far as we can tell, the function of nerve cells in lower animals. All of a sudden, in the homo genus, this is supposed to have been reversed so that quantum uncertainty becomes the source of consciousness? I don't buy it in the least bit. If it did turn out to be true it would be one hell of an argument in favour of intelligent design, but I'll need extraordinary proof before I believe that extraordinary claim. More probable, to me, is the idea that at least one necessary ingredient for the development of consciousness is a certain level of complexity and capacity in the brain to allow it to hold competing and complementary functions and concepts.
A much more interesting book on a related subject is Susan Blackmore's The Meme Machine exploring the idea that memes are the second type of replicator (competing with genes in) driving human evolution and forcing the increasing complexity and capacity of the human brain. Check out her tittilating collection of articles on her web site. I've got Susan Blackmore's book on Consciousness on order and am looking forward to reading it when I get it. A different, but complementary, volume is Andrew NewBerg, Eugene d'Aquili, and Vincent Rause's Why God won't go away: Brain Science and the biology of belief - highly recommended.
Still, Penrose is extraordinary when he sticks to his bailiwick of physics and mathematics and I look forward to picking up a copy and reading his latest on modern physics, even if I find his opinions on consciousness and neurology worthless.
Laissez lire, et laissez danser; ces deux amusements ne feront jamais de mal au monde. - Voltaire
It really is that bad. Nature called it "a masterpiece of psuedoscience".
AI as a field has its own problems, but these guys aren't helping.
He should have been content to convey the qualities of the book, but he couldn't contain his literary aspirations.
.... Yay, Slashdot.
Jeez, the guy writes well, that's a problem?
We see so many moronic and contentless articles posted that are written in dumbed down US street-cred speak, and they pass without criticism. Add a small amount of literary flair, and it suddenly stands out from the usual burps and grunts and needs to be put down
Ugh... I thought GEB was just intellectual masturbation. A few years ago I voiced the same opinion on some newsgroup and a lurker emailed me to say that he'd attended lectures given by Hofstadter and the guy was just so smug and full of his own cleverness.
By contrast Emperor's New Mind is one of the best books I've ever read, rich and fertile and full of ideas that actually lead somewhere other than the ooh! aah! of intellectual fireworks.