Cosmology’s Century
by P. J. E. Peebles
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Modern cosmology began a century ago with Albert Einstein’s general theory of relativity and his notion of a homogenous, philosophically satisfying cosmos. Cosmology’s Cent
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All Reviews

Kin YipKin Yip wrote a review
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Spoiler Alert
It is not really a popular astrophysics book written for laymen, like many of those from Brian Greene's. It's a tour-de-force effort by the author to illustrate many facets of the evolution of various cosmological ideas and theories leading to the present standard model of cosmology, ΛCDM. I've found it non-trivial and often difficult to understand every detail that the author discusses in this book. I probably need to read it over 10 more times to understand everything :-( :-) People without an academic physics background probably wouldn't enjoy reading it, I think. The author probably didn't really make any real effort to allow laymen (without physics background) to be able to comprehend what he discusses in this book.

Let me write down a few cute details that I have learnt:

Chapter 3: I didn't know/realize that the popular and influential cosmological model for about half a century or so ( Ωm=1 with zero space curvature and zero cosmological constant) is actually called the "Einstein-de Sitter model (1932). It took a lot of time and efforts for physicists to abandon this model and to get to the recent cosmic mean mass density of Ωm≈0.3.

On p.122 (Chapter 4), the author commented that: "George Gamow was a genius at creative physical intuition." (10th line) and "Perhaps great intuition must be accompanied by indifference to details." (lines 12-13). 😁 Before this book, I have never read that Gamow has actually not paid attention to details, to try to explain to his colleagues or even himself. Near the end of p.350, the author seems to imply that if Gamow could have paid attention to details, he might have helped discover the cosmic microwave background and advance to where we are considerably earlier.

Chapter 4: quite a few groups have noticed the "excess noise" and could have discovered the Cosmic Microwave Background. Penzias and Wilson made the Nobel Prize discovery because they "did the right thing: they did not give up the search for the noise source in the instrument or local surroundings" (p.158, lines 12-13 from the bottom).

There are many dark matter (DM) models. Apparently, in the simplest term, hot dark matter (HDM) originated with "thermally produced sea of neutrinos with rest mass of a few tens of electron volts" (p.313, lines 6-7 from the bottom), which have large velocity disperson. Cold dark matter (CDM) was first thought to be ~3 GeV neutrinos or WIMPs (weakly interacting massive particles), which have negligible primeval velocity dispersion. And warm dark matter (WDM) arose from the thought that supersymmetric particles might be responsible for the mass of a large galaxy.

Another "tidbit" that I have learnt (or don't remember ever hearing it before) is: though the "Supernova Cosmology Project" (Perlmutter et. al.) has got two times more supernovae at larger z/redshifts than the "High-Z Supernova Search" team (Schmidt, Riess et. al.), the latter group (with some help from Calán-Tololo team) has had "superior experience in the art of astronomical photometry" (p. 328, 29th line). As a result, the two teams have placed "similarly tight" constraints on the z-m relation and cosmological parameters.

The most meticulously described topics in this book are the measurements of the cosmic mean mass density and how physicists have tried to solve the problem of excess subluminal mass to eventually arrive at the conclusion of nonbaryonic dark matter. I have been aware at least a little about the importance of the latter but I didn't realize (before reading this book) that the physicists have struggled so much in trying to convince yourselves that Ωm is much smaller than 1. This is a book with interesting history including the author's own and very sophisticated illustration of the complicated interactions between different branches of astronomy and astrophysics. I imagine that a serious starting graduate student or a postdoc would benefit from it tremendously. Finally, this book probably shows to an extent why the author has been awarded the Nobel Physics Prize in 2019.

p.26 (2nd line) and p.87 (8th line from the bottom), I think the word "statical" is meant to be "statistical".
p.27 (6th line from the bottom), "correlation correlation function" should be just "correlation function" 😀
p.45 ( lines 14-15 from the bottom), the words of "first" and "second' --- about the two equations in equation (3.3) --- in these two lines should be interchanged. Because d^2a/dt^2 = - GM/a^2 (16th line from the bottom) is really the second of equation (3.3) when p and Λ vanish, not the first.
p.50 (last line), first part of equation (3.20), dP/dτ = 3He^(3Hτ)
should be dP/dτ = 3He^(-3Hτ) (i.e., negative in the exponent) as can be seen from equation (4) in the article of "Sciama, D. W. 1955" (one of the references of this book). And also, it seems to me that only with this negative sign, can one arrive at P(t) in equation (3.24).

p.107 (8the line from the bottom), "Table 3.5" should be "Table 3.3" (the last Table of Chapter 3 on p.108 and there is no Table 3.5 in this book).
p.132 (lines 1-2): "The explanation is to be seen as follows" ends without a paragraph of quotation or a period "." ?! Something seems to have been missed here ?!
p.155, "lake Camo" on 8th line and "Lake Camo" on 18th line, should most likely be "Lake Como". ( I can't find "Lake Camo" in whereas "Lake Como" is well-known. ) This is not the author's mistake but probably Hoyle's as I have found the same misspellings in Hoyle's lecture, "Fifty Years in Cosmology" (p.5).
p.166 (1st line), the sentence " ... it is consistent the thermal spectrum." is missing the word "with" after the word "consistent".
p.197, in equation (5.16), the rightmost expression of ϕ should have a negative sign.
p.205, words on the 7th line (not counting the equations) seem to be crammed together and there is almost no space between words (except between "." and "The"). There are a few other lines like this but this line has the most serious problem :-)
p.220 (last two non-footnote lines) : "It presents and an opportunity for more research." shouldn't have "and" in that sentence.
p.241 (lines 22-23): "made" in "The underestimate did made the galaxies seem to have curiously large masses ..." should be "make".
p.271, in the caption of "FIGURE 6.6", there should be a comma "," at the end of 4th line (before "the disk ..." at the beginning of the 5th line).
p.320 (22nd line), a period "." is missing after " ... 𝑙 = 400" before "This is allowed ...".
p.326 (4th line from the bottom), " ... the time the scale ..." should probably be " .. the time scale ..." (without the second "the").
p.339 (10th line from the bottom), "a" in "... case for the ΛCDM theory about a compelling as it gets ..." should be "as".
p.353 (lines 14-15), a comma is probably missing in the sentence "Since it is so clearly wrong (as discussed on pages 235 and 236) why was the idea ..." after the closing bracket ")" and before the word "why" ?