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Nico
  • Member for 5 years, 7 months
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  • Berlin, Germany
16 votes
2 answers
900 views

Reference request: Bundles in Algebraic Geometry

8 votes
1 answer
282 views

Is exercise 2.22 (iii) in Rotman's Homological Algebra book wrong?

5 votes
1 answer
378 views

Existence elimination in Lean 3

5 votes
1 answer
118 views

extension of regular logic

5 votes
0 answers
61 views

Question about a forgetful 2-functor in Tom Leinster's *Higher Categories, Higher Operads*

5 votes
1 answer
129 views

sheaves on a scheme

5 votes
1 answer
122 views

How many smooth vector space structures does $\mathbb R^n$ have?

5 votes
2 answers
155 views

What is the universal property of the thickening $Y[\varepsilon]$?

5 votes
0 answers
95 views

Stackification of finite categories

5 votes
1 answer
78 views

Sheaf topos is localisation at covering sieve inclusion

4 votes
0 answers
83 views

Stack comparison lemma

4 votes
0 answers
109 views

Functor of points of $X_{red}$

4 votes
1 answer
112 views

Must every $\mathbb Z$-shaped point of an arithmetic scheme be contained in an affine open subscheme?

4 votes
0 answers
85 views

Examples of Pseudo-adjunctions

4 votes
1 answer
210 views

Mistake in B. Jacobs book Categorical Logic and Type Theory?

4 votes
1 answer
145 views

2-categorical universal property of the classifying category of a type theory

4 votes
2 answers
840 views

Every ring morphism from an integral domain to a field is injective?

4 votes
1 answer
145 views

$R$-module maps $R\times R \to R$

4 votes
0 answers
390 views

homotopic cycles are homologous

3 votes
0 answers
70 views

non-constructive existence of a number

3 votes
0 answers
44 views

invariant closed subset under group scheme action (Mumford GIT)

3 votes
0 answers
68 views

Does the Barr-embedding preserve coequalizers

3 votes
2 answers
144 views

Can I recover the Zariski open subobjects from the Grothendieck topology they generate?

3 votes
2 answers
163 views

What is $\mathcal O(S\times \mathbb A^n_\mathbb Z)$?

3 votes
0 answers
36 views

are comma-objects semi-coflexible

3 votes
1 answer
80 views

excisive couples, sufficient conditions

2 votes
2 answers
133 views

A local approach to adjunctions in a 2-category

2 votes
1 answer
227 views

What *is* a geometric formula?

2 votes
1 answer
100 views

Singular Chain complex of Smash Product

2 votes
0 answers
63 views

Geometric meaning of the grading of a module