Customer Reviews

General Relativity: An Introduction for Physicists

5 star:		(2)
4 star:		(1)
3 star:		(0)
2 star:		(1)
1 star:		(0)

 

 

I was the TA for an undergraduate course that used this book. I read the book to reference equations when writing up homework solutions, and in response to students questions about it, but not otherwise. That is, I did not read it cover to cover, but selectively. However, almost invariably when I read a section I would think that something in it was either confusingly presented or simply wrong. I kept a list of my "grievances" as the semester went along, and I am writing them as part of this review. I probably should give the book one star, based on my experience, but since I haven't read very much of it, it's conceivable that other parts are very good. (So, it gets two stars.) Also note that the students uniformly complained about the book.

1. P. 10, treatment of length contraction. The equation for length contraction is "derived" with no discussion of simultaneity. Essentially, the book writes dx = gamma ( dx - v dt ), and sets dt=0 so that dx is "length". This is not a correct derivation without more explanation, because (for example) using the inverse Lorentz transformation would give the opposite answer. None of the words in the book explain why the the Lorentz rather than inverse Lorentz transformation should be used. It's just not possible to give a correct treatment of Lorentz contraction without being careful about the notion of simulteneity. (It also would help to have a spacetime diagram.) You need to say what length means in each frame, and then compare them. This came up because I was giving students very little credit on a homework problem that was essentially "derive length contraction", and it turned out they had copied out of the book.

2. P18,p117, notation for three-velocity. The book adopts the totally absurd convention of denoting the three velocity by \vec{u} and the four-velocity by u^alpha. Of course, the three-velocity is not equal to the spatial components of the four-velocity, so this notation is incredibly confusing (if not inconsistent, since u^1 would denote both the 1 component of u^alpha and of \vec{u}). A veteran of relativity can follow even an inconsistent notation, but this is incredibly confusing for somebody trying to learn the subject (which is the point of the book). I got lots of confused questions from students about this one, and no surprise. There are plenty of letters in the alphabet--choose a different one for the three-velocity!

3. p120, second paragraph. This one is so ridiculous I can't believe it made it past the first reprinting. The authors write, "So far, we have not mentioned the frequency (or energy) of the photon, which characterises it in much the same way as the rest mass m_0 characterises a massive particle." This is of course completely false. The rest mass is an invariant quantity, whereas the frequency/energy depends on the frame. The analog of the rest mass for photons is zero, the invariant quantity of zero rest mass. The analog of photon energy is particle energy. Frequency has to do with quantum mechanics and has no analog I'm aware of. This sentence sticks out like a sore thumb to anybody who has done some special relativistic kinematics. Again, I simply can't believe it wasn't caught as a mistake by the reprinting.

4. p21, discussion of uniform acceleration. This is a more minor point, but I don't think the authors do a good job of explaining the concept of "uniform acceleration". Uniform acceleration usually does me "uniform four-force", which is very confusing terminology. I think the authors could do a better job of pointing this out. Let me emphasize that this point is minor in comparison with the others

5. p123. The authors say that free particles move on "non-null" worldlines, rather than on "timelike worldlines". Again, this sticks out like a sore thumb; it should have been caught and fixed.

6. p183 and elsewhere. The authors write R^{\mu}_{\nu} instead of R^{\mu}_{\ \nu}. While it is indeed unambiguous to do this for symmetric tensors, I don't see the point. There is a perfectly good notation that works for all tensors, and doesn't need statements like "by the way you can check that both natural interpretations of this notation are in fact equivalent" to define it. Why confuse students with an index operation that is only okay for certain tensors? They are trying the best to get to grips with index notation, already. I think this is a very poor decision pedagogically.

7. p188-189, treatment of point particles. The authors give a very silly discussion of point particles in general relativity. To be clear, there are no solutions in general relativity with point particle stress-energy (see the paper by geroch and traschen). Yet, the authors say (for example) "the position of the particle is where the field equations become singular". It is fine to present the calculation that point particle stress-energy will be conserved only for geodesic motion, but don't pretend there is anything more to it than a (very) suggestive calculation. Since no solutions exist for that stress-energy, you haven't shown anything about the motion of particles in GR. (At the very least, don't discuss the field equations without pointing out that there are no solutions!)

Again, I haven't read the whole book, but you can understand from above why my impression of it is poor.

I have this book along with the classic by Misner, Thorne, and Wheeler. Both are good, but I like the explanations in this book better. I think it benefits from being published in 2006. Physicists have learned how to explain General Relativity better. Misner, Thorne, and Wheeler is 3 times thicker and covers more topics, but this is actually a distraction from learning the subject for the first time.

Another advantage of being published in 2006 is that the quality of presentation has improved.

I recommend the book.

While looking for a book to teach my undergraduates I was lucky to obtain a copy of this book.I was ready to implement the Nightingale/Foster , but I was disappointed to see the degradation of its second edition. I learned GR with the first edition of N/F!!!.
Well , I checked this excellent book and I was amazed.
In the first chapters the authors expose Vectors tensors and manifold in the easier possible way. Then they revise Special Relativity . Then , they proceed as usual , Curved spaces , Einstein's Field Equation , Scwh-Metric, Schw -Black Holes , Interior solutions, but , then : Kerr solution in great detail!!. Without going into Ehler's equations or Degenerated Algebras , the authors describe very well Kerr's Geometry and Physics ( Penrose's , Celestial Mechanics..etc).
Cosmology ( FLW) solutions ,..Inflation in some extent!!..Linearization and Gravitational Waves (Production and detection) .At the very end there is the Hilbert action etc.

I wish some Kaluza/Klein , which is possible and necessary for the new generation ( to understand completely String Theory you need to taste KK- theory ) and also , I wish a given amount of solution for the large number of problems at the end of every chapter.

I hope to see both of these in future versions of this magnificent introductory book and then I will give the 5-star.

The authors provide the reader with a clear account of modern general relativity (and cosmology). They present the important ideas as simply as possible. They try to teach --- not to show off their mastery of the latest greatest notation and abstraction.