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Jan Weidner

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Name Jan Weidner
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Location Freiburg
Age 25
81

Questions
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73
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6k
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What is torsion in differential geometry intuitively?

dec 16 at 6:48 Peter Michor 6,358●1●15●20

35

23

15
21
votes
7
answers
2k
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What is a coalgebra intuitively?

jul 20 at 23:20 Menton 93●3

40
20
votes
7
answers
5k
views

What is the exterior derivative intuitively?

feb 21 at 8:53 Johannes Ebert 11.6k●33●56

11

9

10

21
14
votes
19
answers
2k
views

Examples of categorification

oct 27 10 at 21:27 David MJC 459●4●12

15

1 2 3 4 5 … 9 next

 

28

Answers
votes newest views recent
48
Blackbox Theorems (2)
34
Suggestions for good notation
19
nontrivial theorems with trivial proofs
15
Most striking applications of category theory?
15
What is the general geometric interpretation of modules in algebraic geometry?
9
Things that should be positive integers…really?
9
Faithfulness of derived functor.
9
Awfully sophisticated proof for simple facts (2)
8
Can we define homotopy groups using Tannakian categories
7
Characterizing specific “concrete” mathematical objects by abstract general properties
7
Unit ideal in non-commutative rings
6
Graded local rings versus local rings
6
Intersection of all normalizers
5
Is the direct image of a constant sheaf a constant sheaf?
4
moduli problem for flag varieties?
3
Which commutative algebras admit a nonzero Poisson bracket?
3
Best online mathematics videos? (2)
3
Applications of the “other” definition of Sheaves
2
Subspaces of finite codimension in Banach spaces
2
intermediate/middle extension of perverse sheaves
2
Has there been any application of tensor species?
1
Distinguished triangle of closed - open partition, for D-modules
1
A_infinity structure on cohomology and the weight filtration
1
Does a locally free sheaf over a product pushforward to a locally free sheaf?
1
Combinatorial results without known combinatorial proofs
1
Differential operators on M/G are factor of invariant differential operators on M ? (Quantization commute with reduction ) What is state of art ?
0
Does the Riemann-Hilbert Correspondence work at the DG level?
0
When does ‘positive’ imply ‘sum of squares’?

 

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