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red_trumpet
  • Member for 4 years, 10 months
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14 votes
0 answers
321 views

Can non-reduced fibers appear over a subset of codimension $\geq 2$?

9 votes
2 answers
455 views

Divided power algebra is artinian as a module over the polynomial ring

8 votes
1 answer
438 views

J.-P. Serre: Duality of regular differentials on singular curves

6 votes
2 answers
351 views

Why is the scheme of isomorphisms of sheaves affine over the base?

5 votes
1 answer
270 views

About "strict" short exact sequences in quasi-abelian subcategory of a derived category

4 votes
0 answers
194 views

Why does a deformation modify the complex structure *holomorphically*?

3 votes
1 answer
165 views

Does miracle flatness always fail for a non-regular base?

2 votes
1 answer
297 views

Jordan–Hölder sequence for $\mu$-semi stable sheaves

1 vote
1 answer
128 views

What is the pull-back of a polarization of abelian schemes over different bases?