Skip to main content

All Questions

Filter by
Sorted by
Tagged with
5 votes
1 answer
479 views

About an argument in Olsson's book

The following picture is from Algebraic spaces and stacks (p.54) by Martin Olsson. I don't understand how to conclude that $\alpha$ is induced by a nonzero class in the end. It seems that there might ...
Lao-tzu's user avatar
  • 1,906