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The Fabric of the Cosmos
Now, when I say "easy," this is, like so much of Greene's book, relative. It's taken me three weeks to wade through the concepts and often humorous prose that goes along with them. Being something of a physics geek, I have a basic concept of relativity and quantum mechanics. Greene takes his time laying out classical physics, from Newton to Einstein, exploring the version of the universe presented by the laws of the very large. He then dedicates just as much room enumerating the precepts of the standard model as well as those of quantum mechanics. With these two pillars of modern physics established, we are next whisked on a journey through cosmology, delving further and further back into the history of the universe until both quantum mechanics and relativity break down and we are introduced to strings.
Greene's attention to strings does not overwhelm the book, as in The Elegant Universe, and he doesn't delve deeply into the concepts and math behind any of the theories of physics as in the latter half of his earlier text. What he does present is a very good conceptual overview of modern physics, all the while using the frameworks provided to drive at the central question: What are space and time? (Or "spacetime" as relativity puts it).
This sophomore effort is actually better, I believe, than The Elegant Universe. Greene has a way of explaining things in terms that non-physicists can grasp. His use of pop-culture icons to drive his points home are as masterful as they are funny. It would be my bet that should this book be made into its own television special (and it should) it will have to be a joint work by PBS and Fox. After seeing Greene present his Elegant Universe on PBS, and reading this book, I'm beginning to see him as a new Carl Sagan, or perhaps the illegitimate love child of Sagan and Matt Groening, if such a thing were possible.
In the end, though, the book has left me with more questions than answers. To be sure, Greene and the theories that he covers provide answers, but to conceptualize and understand them is my current difficulty. I'm sure that some of my own problems arise from learning through allegory. Not having the mathematical background to understand these concepts on a more fundamental level is, I'm sure, leading to my own habit of taking an allegory too far. Would the book benefit from a deeper analysis of physics? I don't think so. To take things much deeper would lose those of us without a deep rooting in mathematics. If anything, Greene's work should inspire us to learn more, to grasp the concepts at a deeper level, to understand them in a more fundamental way, if this is indeed possible with the strange world of quantum mechanics.
Greene does delve into what the future of physics could hold. This is, in my opinion, the weakest part of the book. While it is interesting to be exposed to what the 'next big thing' could be, without the grounding that Greene enjoyed in the previous four sections of the book the final chapters prove less fulfilling than the ones that worked towards them. It's not that Greene doesn't explain the concepts expertly, but knowing that we're reading about a theory that hasn't even been fully formed, that is only a step away from speculation, means they don't stand as tall as the previous chapters. People may say this about string theory as well, because it is still very much an evolving theory.
Still, this accounts for no more than the denouement of an otherwise thrilling, work. Having traveled once again with Greene on a journey through physics I can say that I understand what Feynman meant when he spoke of The Pleasure of Finding Things Out; thankfully Greene is a good bit easier to follow than Feynman.
You can purchase The Fabric of the Cosmos from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
If you haven't seen the series of PBS specials, "The Elegant Universe", I recommend that you do. They're free for download from the PBS website IIRC. It's an excellent and very informative discussion of some very interesting concepts.
there was an interesting NPR interview with greene about his new book last week:
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Glad to see someone talking about McTaggart at Slashdot. Those interested in modern philosophical theories of time (particularly Prior's) which take into account the efforts of modern physics to define the physical concept of time (often referred to erroneously as "the" concept of time), could start here.
Those really interested in the possibility of non-physical concepts of time should read Husserl (The Phenomenology of Internal Time Consciousness) and, most importantly, Heidegger (Being and Time).
But only after you've done your physics homework.
Hrm... Possibly. This is, in many ways a lighter read when it comes to M/String theory, not delving so deeply into Kalabi-Yau transformations and the other of Green's work. If you're looking for more in-depth on Strings this might not be the work for you.
It's a better overview than TEU was, Green's prose is more refined, but the level of the target audience is lower as well.
What if it is just turtles all the way down?
I'm afraid that you are somewhat confused. String theory is not the observed behaviour mentioned in step 1. It is the hypothesis/theory mentioned in steps 3 - 5.
Those who would give up essential liberty to purchase a little temporary safety, deserve neither liberty nor safety.
Nearly all modern science, especially physics, relies heavily on inference. Experimental techniques hadn't been invented yet to test the theories of quantum mechanics when they were first put forward, but that didn't make them somehow less scientific. If we had discarded them in 1930, we wouldn't have quantum cryptography or quantum dots or any number of other related and very real technologies emerging today.
String theory will be tested someday, but until it is its still a theory. Of course it isn't a law, and nobody in their right mind is saying it is, but just because we're still at step 3 doesn't invalidate the entire theory...
Sheesh.
Just after the PBS special was made available online, I put together a page with links to all the segments here. That way my friends who were interested could download them and watch them later.
- sm
I can't believe I'm feeding the /. science troll but here goes:
String theory is not a religion for scientists or for anyone else. It is an attempt to fix some of the many technical problems with the Standard Model, SM, (ie the current description of EM, Strong, and Weak forces). We know that the SM is incomplete (besides the fact it's a model and not a theory so it describes but doesn't explain) and there are various ideas of ways to complete (ie find the high energy theory for which the SM is the low energy limit) the SM.
Now, there are other ways to complete the SM including such ideas as Supersymmetry, Little Higgs, Technicolor, etc. Some of these like Technicolor have been ruled out, others like Supersymmetry have not been tested and do not have currently testable predications.
It turns out that String Theory is more ambitious than most of the attempts to complete the SM. Most of the approaches like Supersymmetry and the Little Higgs admit that they are not the fundamental theory and at some other energy scale they are incorrect just like the SM. String Theory does not suffer from this problem. This means that the energy scale of String Theory is very high (much higher than the other "easier" theories) and thusly it's implications for the physical regime that we can currently probe are much more subtle. There is lots of work trying to find what the implications are, but currently there is no concrete evidence for or against String Theory.
Now in 2007ish the Large Hadron Collider will come online and we will have lots of "high" energy data. It will still come from well below the String scale but it will be much higher than what we currently have. The economics of high energy physics are such that we have to now wait long periods of time before we get new colliders.
Strictly speaking the scientific method as taught in schools is not really correct anymore. The days of explaining why rocks fall are pretty much over for most branches of physics. Finding aspects of the universe which are not currently explained is no longer so simple. We need to have theories to figure out what the interesting experiments actually are. This means that having a theory is necessary. High energy Physics has progressed to the point where we have to pick and choose our experiments so in most cases we actually need theories.
The major difference then between String Theory and religion is, we will find observable consequences of String Theory and we will test them. If we find disagreement with theory the theory will be discarded/modified, if it agrees we will look for more consequences to test.
Faster Than the Speed of Light just came out on paperback and is a good read AND a good intro to cosmology.
The End of Time is also available in paperback. I never managed to get though more than 4 chapters, but Barbour has some very intriguing ideas about time, and I've seen him mentioned along with Loop Quantum Gravity, which is a good sign.
Hyperspace was written before TEU, and suffers from age a bit. It was written before Witten unleashed M-Theory on everyone (or just after) I read it immediately after TEU so I bored me, the rehash of Relativity and QM can get a bit tedious in these books unless you spice it up like Greene does.
Three Roads to Quantum Gravity looks promising, and details String Theory's main competitor on the Quantum Gravity front, Loop Quantum Gravity. I picked it up, but couldn't get into it.
I've read Hawking and a few others, but I've never been able to get into things from the 'classical' side of the equasion. Feynman is REALLY difficut to get into, his prose just doesn't flow like Greene's. Perhaps I'm a mass consumer and so esoteric physisits don't appeal to me as authors.
What if it is just turtles all the way down?
The museum of hoaxes has some doubts about Peter Lynds claims...
Disclaimer: If I disagree with you I'm probably trolling...
You speak of brain damage with convincing authority.
Believing that you are one of "the last generation" is surely one of the most common fallacies of the credulous.
Also, you mean "Timewave", not "Time Cube".
In any case, you should probably read this article on the Copernican principle of events. The overwhelming likelihood is that you're not special, friend. Sorry.
Oh, and of course "drugs are for idiots". Like Carl Sagan, you mean? Got it.
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