In my last three major posts (I, II and III) I've been talking you through a mystery: the integrated Sachs-Wolfe mystery. This post will be able to be read on its own, but it you will appreciate it much more if you have also read them. In today's post I will be playing detective, examining the evidence, looking for leads and weighing up the various possible solutions to the mystery. Like any good mystery there are hints as to what the resolution might be, but like any good mystery story some of these hints might turn out to be just be red herrings, so we need to be careful.
Read more at the Trenches of Discovery
