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red_trumpet
  • Member for 4 years, 11 months
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  • Germany
112 votes
34 answers
17k views

Noteworthy, but not so famous conjectures resolved recent years

59 votes
1 answer
6k views

Why "open immersion" rather than "open embedding"?

43 votes
20 answers
19k views

Sources for Bibtex entries

29 votes
1 answer
3k views

Almost Complex Structure approach to Deformation of Compact Complex Manifolds

23 votes
1 answer
4k views

Smooth vs regular vs non-singular

  • 241
21 votes
1 answer
3k views

Minimal number of generators of a homogeneous ideal (exercise in Hartshorne)

20 votes
5 answers
4k views

Automorphism group of a scheme

  • 3,271
19 votes
1 answer
5k views

dualizing sheaf of a nodal curve

  • 2,038
18 votes
1 answer
1k views

A line bundle that does not admit a G-linearisation

9 votes
2 answers
455 views

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

9 votes
1 answer
467 views

Explicit surjection $\mathbb{A}^n\longrightarrow \mathbb{P}^n$

8 votes
2 answers
3k views

Does the fiber product of two normal varieties remain normal?

  • 1,071
8 votes
1 answer
453 views

Is a polarization on an abelian scheme an open condition?

7 votes
2 answers
936 views

Automorphism groups of general type varieties

  • 593
6 votes
3 answers
1k views

Verifying claims in the proof of the Rigidity Lemma (Mumford, GIT)

  • 421
5 votes
2 answers
835 views

Map of coherent sheaves inducing isomorphism on the stalks at the generic point

5 votes
3 answers
850 views

Proving that a map is a morphism

  • 198
5 votes
2 answers
314 views

Does the Kähler form $\omega$ satisfy $d^*\omega=0$?

  • 85
4 votes
1 answer
884 views

Why is the normalization of a general fiber the general fiber of the normalization?

3 votes
0 answers
161 views

Primary decomposition for noetherian schemes

3 votes
1 answer
776 views

the group of all biholomorphic group automorphisms of complex tori