Timeline for Direct factors of Jacobian
Current License: CC BY-SA 3.0
3 events
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| Jul 7, 2017 at 13:39 | comment | added | nfdc23 | @abx: Of course, to make the argument work over finite fields, one should use Poonen's refinement of Bertini theorems to work over finite fields (this being one of the applications in his original paper). | |
| Jul 7, 2017 at 12:36 | comment | added | abx | Any abelian variety $A$ is isogenous to a direct factor of a Jacobian: just take a sufficiently ample curve $C\subset A$, so that $A$ embeds into $JC$, and apply Poincare reducibility theorem. I doubt that you can characterize those for which the isogeny is actually an isomorphism. | |
| Jul 7, 2017 at 11:18 | history | asked | pi_1 | CC BY-SA 3.0 |