Yuhao Huang's user avatar
Yuhao Huang's user avatar
Yuhao Huang's user avatar
Yuhao Huang
  • Member for 13 years, 1 month
49 votes
7 answers
10k views

Why forgetful functors usually have LEFT adjoint?

31 votes
8 answers
5k views

Is there a "knot theory" for graphs?

27 votes
6 answers
3k views

Why are finiteness conditions important (and how to recognize them)?

25 votes
5 answers
4k views

Why does the (S2) property of a ring correspond to the Hartogs phenomenon?

25 votes
5 answers
3k views

Which algebraic varieties admit a morphism to a curve?

24 votes
2 answers
3k views

Why is the decomposition theorem awesome?

17 votes
3 answers
1k views

What are the auto-equivalences of the category of groups?

15 votes
6 answers
3k views

Representation of Groupoids

15 votes
4 answers
3k views

How does one motivates the method of separation of variables when teaching PDE's?

14 votes
2 answers
798 views

What's the easiest example of a morphism of topoi that is not from that of a site?

14 votes
1 answer
2k views

What are p-adic period rings?

14 votes
2 answers
1k views

Can one find the hodge number by counting points over finite fields?

13 votes
4 answers
2k views

Is there any generalization of the Dold-Kan correspondence?

13 votes
3 answers
3k views

What functor does Grassmannian represent?

12 votes
4 answers
6k views

"Counter"-example for Gauss's Lemma on irreducible polynomials

12 votes
1 answer
1k views

Cohomological functor from triangulated category

11 votes
3 answers
2k views

Why is a variety of general type hyperbolic?

10 votes
2 answers
2k views

Does the derived category remember the homological dimension?

10 votes
6 answers
3k views

How do you present a non-existence theorem?

10 votes
2 answers
3k views

What are unramified morphisms like?

10 votes
1 answer
909 views

Characterization of schemes whose dualizing complex is perfect

9 votes
1 answer
429 views

Reverse Engineering to find deformation problem (from cohomology groups)?

9 votes
6 answers
5k views

Figure out the roots from the Dynkin diagram

8 votes
1 answer
972 views

obstruction to smooth lifting of smooth schemes

8 votes
1 answer
620 views

Is it possible to do intersection theory in the derived category of a scheme?

8 votes
3 answers
482 views

Can irreducibility of polynomials be figured out in polynomial time?

7 votes
3 answers
3k views

How many commuting nilpotent matrices are there?

7 votes
6 answers
926 views

Why are the following varieties symplectomorphic?

7 votes
1 answer
298 views

How to see meromorphicity of a function locally?

7 votes
8 answers
705 views

What is an example of a function on M_g?