A couple of posts ago, I gave the slick proof of cohomology and base change that I learned from Eric Larson (and that to the best of my knowledge should be credited to him). Here is the rewritten chapter on cohomology and base change, now only 17 pages long, which incorporates his argument (as well as various other corrections and suggestions people have sent through the years).

ch28jul1522Download

As always, I’m happy to hear of any errors/typos/suggestions!