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Jul 17, 2013 at 12:18 answer added Ralf Meyer timeline score: 3
Jun 21, 2013 at 10:57 vote accept Mikhail Bondarko
Jun 19, 2013 at 19:24 comment added Alexei Pirkovskii Sorry, of course I meant that $\mathrm{Tor}_0^A(B,B)\cong B$, not $A$.
Jun 19, 2013 at 19:13 comment added Alexei Pirkovskii When the categories are module categories, and the functor is restriction along a map $A\to B$ of rings, $D^b(B)\to D^b(A)$ is a full embedding iff [ \mathrm{Tor}_i^A(B,B)\cong \begin{cases} A, & i=0,\\ 0, & i>0. \end{cases} ] See W. Geigle and H. Lenzing, "Perpendicular categories with applications to representations and sheaves", J. Algebra 144 (1991), no. 2, 273--343.
Jun 19, 2013 at 17:25 answer added Leonid Positselski timeline score: 6
Jun 19, 2013 at 7:43 comment added Mariano Suárez-Álvarez When the categories are module categories, and the functor is restriction along a map of rings, such a functor $F$ is called an homological epimorphism. That keyword should produce useful information.
Jun 19, 2013 at 7:21 answer added Sasha timeline score: 2
Jun 18, 2013 at 17:11 comment added Benjamin Antieau It seems like this would happen when $A$ is thick in $A'$ and projectives in $A$ are projective in $A'$. Then, I think $D^b(A)$ can be identified with $D_A^b(A')$, the derived category of complexes of objects in $A'$ with bounded homology contained in $A$, which is a full subcategory of $D(A')$. See Weibel, Exercise 10.4.3.
Jun 18, 2013 at 14:20 comment added Mikhail Bondarko This is true; yet when does this happen?
Jun 18, 2013 at 14:06 comment added anon I'd guess: if and only if the Exts in $A$ and $A'$ agree,
Jun 18, 2013 at 13:34 history asked Mikhail Bondarko CC BY-SA 3.0