xviii Preface to Fourth Edition
necessary in order to make space for all the new matter. What has disappeared was
standard particle physics which should be known to the particle physics readership
(the astronomers do not care).
In Chapter 7 on inflation the currently popular single-field model is rewritten and
much expanded.
In Chapter 8 on the cosmic microwave background the emphasis has been shifted
from the WMAP satellite to Planck, and all the parameter values have been updated.
Dark matter has been dedicated its own Chapter 9, very much enlarged from the
material in the previous edition, and concentrated on the abundant observations of
its gravitational effects. Very little is said about dark matter candidates since that is
all speculative.
In the very short Chapter 10 on cosmic structures there is nothing new added.
Finally Chapter 11 is devoted to dark energy, almost entirely new in this edition.
I have enjoyed the support of the Magnus Ehrnrooth Foundation for the work on
this Edition.
Matts Roos
Helsinki, May 2014