Notice: I am writing more than one review in a month, good for me! To be fair, I didn't write anything in July. And I actually finished Middlesex in July. To also be fair, I am over halfway through my current read (within two days; it's going quickly) and will likely be reviewing that fun dude before the end of the month. If you want a whopping great clue as to what that book is, click here to see that it's been a while and I may or may not be grateful (for the first time ever) for authors who casually (or even not-so-casually) recap the previous book(s) within the narration.
I'm a bit loopy from a few weeks of low-quality and grudging sleep for no apparent reason, so...this could be fun. If it isn't already.
In The Elegant Universe, physicist Brian Greene tells the story of string theory, the theory that might be the answer to the conflict at the center of the last hundred years of physics, and might be the ultimate theory of everything. He begins with descriptions of relativity and quantum mechanics, then details how they clash and cannot both be correct in their current formulations. The remainder of the book is an explanation and exploration of string theory's history, workings, successes, puzzles, and potential.
Now, onto the actual book (I'm so sorry). I quite liked The Elegant Universe. Greene's writing is engaging and flows well. I always appreciate it when science writers make mild jokes in their books because they sound so tentative and like old British men (which is actually what Stephen Hawking is, so at least is his case that's perfectly accurate). But I try not to laugh at them because who knows, maybe one day I'll be a science writer who makes tentative, old-British-man jokes, too. And it is actually funny that "p-brane" is a term in string physics. I suppose.
I feel like I read a lot of this book while I was tired, but then again I have been tired for most of this month.
The subject matter of The Elegant Universe is definitely difficult and technical, but I found Greene's presentation mostly accessible (for context, my science background goes up to high-school physics and chemistry, plus some noodling about with astronomy and astrophysics for fun and Science Olympiad, and my math background goes through advanced high school algebra, plus some random set theory because, like the nerd I am, I once took an online mathematical philosophy course. I'm no expert). It's never going to be possible for humans to fully understand what a six-dimensional space looks like, or how such Calabi-Yau spaces could be so small that we cannot observe them while also being literally everywhere constantly. But Greene elaborates as much as possible while still remaining accessible. He is never condescending, only occasionally giving the impression of an overly-cheesy "big reveal." His writing was clear and engaging enough that I was able to read the nearly-400-page book in three weeks, which definitely recommends it, because I am a slow reader who loves perfectly understanding books and also listens to podcasts a lot.
I thought that Greene presented the most lucid explanation of general relativity that I have ever read. To be fair, I have not read many explanations of general relativity; the only specific example I can think of that was in a book is in A Brief History of Time. But Hawking's explanation was so furiously confusing that I eventually got lost because I didn't know what a geodesic was and it seemed to be very important but I didn't get it because I can't geometry very well, especially when I have to picture things entirely in my own darn head because apparently a figure wasn't deemed necessary. But Greene's explanation relied on no unillustrated geometric weirdness and made perfect sense. I also appreciated his full review of the basics of quantum mechanics; my knowledge is so fragmented and comes mainly from chemistry class where we only learned the chemistry-relevant bits, so it was really great to be able to see it all together and, especially, to understand what I already knew in the context of the history of quantum mechanics.
Greene has certainly gotten me interested in string theory. I do wonder what its state is now, considering that this book was updated fourteen years ago and a lot has happened since then, namely the construction and run of the Large Hadron Collider. String physicists, Greene included, were really banking on many aspects of string theory being confirmed in the run of the LHC, and as far as I know that didn't quite happen. I would like to look more into the current state of string theory.
As an astrophysics and cosmology nerd, I appreciated the view near the end of string theory in cosmology.
The Elegant Universe left me with a lot of questions. The main one: How do we know that an ultimate theory is even possible? It bothered me for a good two-thirds of the book, and then in the penultimate chapter Greene finally addressed it. I was glad about that. But I still do not have an answer, and there may not even be an answer. I also wondered how you could ever set a limit to explanation. So say that the universe is made of vibrating strings and that's that. But why strings? Why vibrations? I find the anthropic principle to be a weirdly satisfying sort of shut-down to these kinds of questions but I'm interested in all its implications. Also, can anyone tell me what energy actually even is? And how on earth can you make a universe with four extended dimensions and six or seven curled-up dimensions from one-dimensional objects? I mean, it's sure better than zero-dimensional point particles as the standard model of particle physics proposes, but I'm still confused and irritated. Help.
And I consider all those questions to be good aspects of the book. Even if they weren't answered. A great science book should always leave you outraged...I guess.
Before I get into the one less-than-amazing part of The Elegant Universe, I want to talk about chapter ten, Quantum Geometry. That chapter had me utterly riveted and staring at the page, eyes zipping along. Radius duality was a better story than a lot of fiction I've ever read. Despite the warning that some sections were a bit abstract and we shouldn't worry if we don't get them initially, I found the chapter perfectly easy to understand because it was so fascinating (although maybe I only think I understand it). So our universe could actually have a radius the inverse of what we think it is and we'd never know, no big deal.
The only thing that bothered me was that Greene got stubbornly quiet at times, and suspiciously so because it looked a bit like he didn't actually know what he was talking about. Like in the chapter on supersymmetry, which made me mad because he didn't actually seem to explain what supersymmetry is, with the excuse that the math's too complicated. He seemed to have a perfectly fine time using relatively simple language to write about concepts with incredibly complex mathematical origins, descriptions, and proofs. So, Greene, do tell why you couldn't possibly seem to get your (annoyingly vague) section on spin to connect to supersymmetry in a way that any reader could logically follow. Or the part about string loop processes, where the diagrams of virtual strings and such looked identical to previous diagrams of non-virtual strings. Like I understand particles and antiparticles (or strings and antistrings) and all that, and I more or less understand that virtual particles can appear from energy borrowing and other such quantum fun. But that diagram with a bunch of virtual strings truly looks no different to me from a pair of strings merging and separating over and over again.
Say hi to my hand and my curtains.
Oh, I also got fairly annoyed with Greene's inability to decide whether to call the six-dimensional manifolds that might match the shape of our universe's curled-up dimensions Calabi-Yau shapes or Calabi-Yau spaces. The terms may be interchangeable, but one really ought to be consistent within one's own book.
In short, I would recommend The Elegant Universe to anyone with an interest in physics and the universe. And I'm so sorry about the above mess.