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Sep 23, 2014 at 5:43 vote accept Nathaniel Bottman
Nov 28, 2013 at 3:22 answer added Sasha timeline score: 5
Nov 27, 2013 at 22:18 answer added Dan Petersen timeline score: 5
Nov 27, 2013 at 22:17 history edited Nathaniel Bottman CC BY-SA 3.0
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Nov 27, 2013 at 22:16 comment added Nathaniel Bottman @QiaochuYuan thanks! If preservation of limits and colimits is an important consequence, then I will try and think about what that means for the derived category of coherent sheaves. I guess I failed to mention in my question that what I'm really interested in is geometric consequences for $D^b$, not "abstract nonsense consequences" that always happen when both $(F,G)$ and $(G,F)$ are adjoint pairs.
Nov 27, 2013 at 22:02 comment added Qiaochu Yuan Consider also the example of the diagonal functor $C \to C^2$. The left adjoint of the diagonal, if it exists, is the coproduct. The right adjoint, if it exists, is the product. They agree iff $C$ has biproducts, which is a very special property and in particular implies that $C$ is canonically enriched over commutative monoids.
Nov 27, 2013 at 21:59 comment added Qiaochu Yuan It tells you that $F$ and $G$ both preserve both colimits and limits!
Nov 27, 2013 at 21:57 history asked Nathaniel Bottman CC BY-SA 3.0