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kaiser
  • Member for 9 years, 3 months
  • Last seen more than 8 years ago
26 votes
7 answers
55k views

What is the essential difference between ordinary differential equations and partial differential equations?

7 votes
2 answers
1k views

Between complex numbers and quaternions?

5 votes
2 answers
271 views

Can $S^4$ be the cotangent bundle of a manifold?

4 votes
0 answers
241 views

Why is the singular $p$-simplex called singular?

4 votes
0 answers
304 views

Geodesics without a metric

4 votes
3 answers
256 views

Any manifold other than $SO(n\geq 3)$ having $\mathbb{Z}_2$ as the fundamental group?

4 votes
1 answer
214 views

Module-vs-vector space, a sentence in the book by Blyth

4 votes
1 answer
2k views

Not every submodule has a complement submodule

4 votes
2 answers
388 views

Jordan canonical form for $m\times n $ matrices?

4 votes
1 answer
769 views

Why is the secant variety a variety?

3 votes
2 answers
462 views

How to understand the Möbius transform as a group action?

3 votes
3 answers
470 views

Why is $n_1 \sqrt{2} +n_2 \sqrt{3} + n_3 \sqrt{5} + n_4 \sqrt{7} $ never zero? [duplicate]

3 votes
1 answer
687 views

Groebner basis and syzygy

3 votes
0 answers
179 views

Why affine variety not vector space variety?

3 votes
0 answers
69 views

Join variety of two non-parallel lines

3 votes
1 answer
657 views

What is the general form of an area-preserving map of $\mathbb{R}_2$?

3 votes
0 answers
427 views

Parallel transform of a vector by Lie derivative

3 votes
1 answer
78 views

Can $S^4$ be the cotangent bundle of a manifold?

2 votes
3 answers
136 views

Can we bypass connection?

2 votes
0 answers
29 views

How to calculate this integral (with limit afterwards)?

2 votes
0 answers
78 views

what do the branch points of a function tell about the function?

2 votes
1 answer
226 views

Symplectic transform between pairs of Lagrangian subspaces

2 votes
1 answer
127 views

Vector space whose dimension is nontrivial to determine [closed]

2 votes
1 answer
71 views

Why only one $\infty $ point for each parallel class of lines in $\mathbb{R}^2$?

1 vote
0 answers
119 views

Invariant theory and irreducible representation of a group

1 vote
1 answer
536 views

Stokes phenomenon of the Airy function

0 votes
1 answer
289 views

The concept of continuity in a topological group

0 votes
2 answers
2k views

$\mathbb{Q}$ is a torsion-free $\mathbb{Z}$-module which is not free?

0 votes
1 answer
168 views

Why is the group ring just a ring, not a field? [duplicate]

0 votes
1 answer
345 views

About the Hilbert basis theorem (number of basis polynomials)