HeinrichD's user avatar
HeinrichD's user avatar
HeinrichD's user avatar
HeinrichD
  • Member for 7 years, 6 months
  • Last seen more than 4 years ago
19 votes
3 answers
1k views

How to construct a constructive proof from a non-constructive proof using prime ideals?

19 votes
2 answers
2k views

Locales as geometric objects

17 votes
4 answers
2k views

Constructive proof that a kernel consists of nilpotent elements

17 votes
1 answer
411 views

The possible degrees of $\mathbb{Q}(a,b)$ in terms of the degrees of $a$ and $b$

16 votes
1 answer
689 views

Classification of non-Hausdorff topological vector spaces

14 votes
1 answer
582 views

Arrangement of the introduction of a paper

12 votes
1 answer
431 views

Is there a categorical notion of reduced commutative algebras?

10 votes
1 answer
473 views

Properties of the petit Zariski topos

9 votes
2 answers
892 views

Algebras whose subalgebras are finitely generated

9 votes
1 answer
393 views

Cocontinuous product-preserving functor between Grothendieck toposes

9 votes
1 answer
388 views

What is this symmetric simplex category, concretely?

8 votes
0 answers
178 views

Zappa-Szép products of the group of integers with itself

8 votes
1 answer
652 views

Presentation of the covariant power set functor

8 votes
0 answers
169 views

Sharply less regular cardinals in set theory

7 votes
1 answer
338 views

Pushouts of injective monoid homomorphisms

7 votes
1 answer
262 views

If $M \otimes -$ is continuous, why is $M$ f.g. projective? Alternative proof

7 votes
1 answer
405 views

Reference for dualizable chain complexes

6 votes
1 answer
251 views

Hopf algebroids without antipode

6 votes
1 answer
435 views

Comonoids in the category of monoids

6 votes
0 answers
178 views

Combinatorial game similar to Sprouts

6 votes
2 answers
594 views

Limit of a sequence of locally presentable categories

5 votes
0 answers
98 views

Zappa-Szép products of the monoid of integers with itself

5 votes
1 answer
242 views

Slick construction of Hochschild complex

4 votes
0 answers
139 views

Amalagamation of a sequence of closed immersions of schemes

4 votes
1 answer
188 views

Decomposition of $\Gamma$-modules into simple objects

3 votes
0 answers
134 views

Colimits of algebras of an endofunctor

2 votes
0 answers
150 views

Lifting a local section to a global section along a homomorphism of quasi-coherent sheaves

1 vote
1 answer
359 views

"Pointwise" defintions in category theory