If you have the revised second edition (from the December 2008
reprinting onwards, identified by having 6 Advanced Topic chapters
rather than 5), the only known errors are:

Page 59, 3 lines after Eq8.6: For the quoted parameter values the
age should be given as approximately thirteen billion years (not
fourteen). To get the commonly-quoted fourteen billion years, the
matter density has to be taken a little smaller.

Page 80, line 13: The bracket should refer to Problem 10.6, not 10.5.

Page 109: The formula given in Problem 13.3 differs slightly from
the version given as Equation 11.12; ideally they would have matched.
The latter is more accurate, but for the purposes of the Problem the
numerical difference is irrelevant.

Page 171: The answer to Problem 12.2 should be given as Y_{4} =
0.04 (I changed t_{nuc} from the earlier editions and forgot to
correct this).

If you are reading the German language edition (published 2009),
click here.

Errata for the original second edition (pre December 2008 reprinting):

In addition to those listed above, the known errors in the original printing are as follows

Page 16: The answer to Problem 2.5 seems to be wrong -- see item for
Page 163.

Page 17: The last sentence of the second paragraph would be clearer
if it said something like `Because a force on an object induces an
acceleration which is also proportional to its mass ...'

Page 22: After Eq3.11, the gas should be in a `cylinder', not a
`piston'. Before Eq3.13, it is stated that the chain rule is used
for its derivation; while the chain rule is used for the first term,
the
main rule being used is the product rule for derivatives. After Eq3.13
it should be *rate of* change of volume, and after Eq3.14 the expansion
could be additionally described as adiabatic.

Page 38: I'm not at all sure `diminishment' is a word in modern
English (though the OED does recognize it). `Diminution' would be
better.

Page 74: Note the answer to the first part of Problem 9.1 given on
page 164 is
wrong (see below).

Page 76: The third last sentence on this page should be replaced by
`The second is because the f^{3} on the numerator scales as
inverse volume, corresponding to the evolution of the photon number
density as the Universe expands.' since it doesn't make much sense as
it stands.

Page 81: In the paragraph following Eq10.17, the second sentence is wrong. The exponential clearly doesn't dominate, since in that limit is simply equals one. However the Saha equation only makes sense if the temperature is below the electron mass energy (to avoid electron-positron pair creation), and that coupled with the small baryon-to-photon ratio is enough to ensure that the right-hand side of the Saha equation is small at relevant temperatures well above the binding energy.

Page 87: The numerical values given in Eq11.11 are both incorrect
and
specified to too low an accuracy. Rather than substituting the values
of the temperature and time at equality (which is approximate and
creates
an illusory dependence on *Omega*_{0} and *h*), it
is
better to immediately use Eq11.12. It gives the constants of
proportionality
in Eq11.11 as 1.3x10^{10} K and 1.1 MeV. These constants are
valid
only for energies less than about 1MeV; at higher energies electrons
and
positrons would be relativistic and contribute to the energy density of
the radiation bath. See Kolb and Turner section 3.3 for a much more
detailed
analysis. This correction has implications for the nucleosynthesis
calculation
detailed in the item for page 93.

Page 91: It would be better if the first sentence of Section 12.1
said ` ... helium-4, the most stable of the light nuclei, was formed
...'

Page 93: In Eq12.6, the `D' should not be in italics.

Page 93: Eq12.9 uses the temperature-time relation of Eq11.11 to
compute
the effect of neutron decays on the neutron-to-proton ratio. The
erratum
for page 87 corrects that relation, which changes the time at which
this
ratio is to be evaluated. Tracked through the calculation, this
significantly
increases the final value of Y_{4} to well above the observed
value.
A suitable compensation would take the build-up of the nuclei to happen
at 0.06 MeV rather than 0.1 MeV, leading eventually to Y_{4} =
0.24. Tuning the build-up energy to get the right answer is really
rather
a fiddle though; a full calculation of the deuterium abundance should
include
far more physics than this simple estimate (eg see Kolb and Turner
Chapter
4).

Page 111: In Eq14.1, the strong energy condition would be better
written with a `greater than or equals' sign, rather than just `greater
than'.

Page 116: Missing word: `fourteen billion *years* old'.

Page 122: The claim that a torus has a flat geometry is oversimplistic. It is possible to have a torus with a flat geometry, most easily realised by identifying the edges of a cube, and this `flat torus' is a valid model for the Universe. However bending a two-dimensional torus to embed it in 3D as a bagel will distort it meaning it is no longer flat. It also no longer has constant curvature and such an embedded torus is not a good model for the Universe. For more details on topology see Janna Levin's review article.

Page 139: A more accurate version of EqsA3.3 and A3.4 would have 94
on the denominator rather than 90. The difference arises because the
mean
thermal energy of a fermion in a thermal distribution is actually 3.15
*k*_{B}*T*,
rather than the 3*k*_{B}*T* I had taken.

Page 140: The Boltzmann suppression factor in A3.2.2 has been
inadvertently written the wrong way up. It should be

exp(-m_{nu}c^{2}/k_{B}T).
This
discussion
is also oversimplistic in implying that the exponential
is all that is needed; a full calculation needs to account for the
breakdown of thermal equilibrium once the particle density becomes too
low, which cuts off the exponential decrease in a process known as
`freeze-out'. This is discussed for instance in Kolb and Turner's book
"The Early Universe".

Page 141: There is a typo on the 6th line of Problem A3.1; the word
`put' should be replaced with `by'.

Page 158: There is a typo in the first line of Problem A5.2, with
the
phrase `the Universe' duplicated.

Page 163: The answer to Problem 2.5 blithely states that the peak of
the frequency spectrum of the Sun will `unsurprisingly' lie in the
visible part of the electromagnetic spectrum. After all, everyone knows
Wien's displacement law placing the wavelength at 500nm. However,
because of the non-linear transformation between wavelength and
frequency, the peaks don't actually satisfy the relation f = c/lambda,
and
when
expressed in frequency the maximum in fact lies slightly into
the infrared.

Page 164: The first answer to 9.1 should be 28h^{2} (or maybe 29h^{2}
depending on the rounding used for the Boltzmann constant). Anyway, not
31h^{2} as given. This
changes the upper limit on the Hubble constant to h<0.60. Note also that the upper
limit on the neutrino mass has strengthened considerably as compared to
the value used in this question, and is now below 1eV.

Page 165: In the answer to A1.1, the sinh should not be squared. The
square root inside the sinh covers the |k| but not the *xi*. The
numerical
answer is correct.

If you've spotted something else, why not tell me at a.liddle@sussex.ac.uk?

Back to the home page of the book.

Andrew Liddle

Last update: November 2010

Last update: November 2010