User Dominik

224 votes

2 answers

8k views

Is there a 0-1 law for the theory of groups?

asked Jun 30, 2013 at 20:26

191 votes

5 answers

7k views

A Topology such that the continuous functions are exactly the polynomials

asked Jun 23, 2013 at 16:00

64 votes

2 answers

31k views

Is Serge Lang's Algebra still worth reading?

asked Apr 7, 2013 at 20:41

48 votes

2 answers

4k views

Is every group the automorphism group of a group?

asked Dec 8, 2012 at 19:02

34 votes

3 answers

5k views

Why should "graph theory be part of the education of every student of mathematics"?

asked Apr 26, 2013 at 20:35

33 votes

2 answers

1k views

Is $ \pi $ definable in $(\Bbb R,0,1,+,×, <,\exp) $?

asked Jun 9, 2013 at 22:50

30 votes

4 answers

3k views

If two non-overlapping squares inside a unit square have side lengths $a$ and $b$, prove that $a+b \le 1$.

asked Nov 25, 2012 at 19:42

24 votes

1 answer

959 views

Is $\Bbb R$ definable in $(\Bbb C,0,1,+,*,\exp)$?

asked Jun 12, 2013 at 16:04

23 votes

4 answers

2k views

What are the important theorems in the theory of dynamical systems?

asked May 10, 2013 at 20:52

19 votes

3 answers

2k views

Are there interesting rings without unity?

asked May 5, 2013 at 17:31

19 votes

1 answer

2k views

Is the space of smooth sections of a vector bundle finitely generated as a $C^\infty$-module?

asked Apr 10, 2014 at 15:01

17 votes

1 answer

662 views

How confident can we be about the validity of the classification of finite simple groups?

asked Apr 1, 2013 at 23:35

17 votes

5 answers

3k views

Most astonishing applications of compactness theorem outside logic

asked Jun 7, 2013 at 12:20

16 votes

3 answers

3k views

Presentation of Rubik's Cube group

asked Dec 2, 2012 at 21:14

16 votes

1 answer

2k views

What are some examples of hard theorems in category theory?

asked Jan 6, 2014 at 18:59

16 votes

1 answer

251 views

Is almost any group generated by two generators?

asked Jul 26, 2013 at 20:51

15 votes

2 answers

953 views

Etymology of Tor and Ext Functors

asked Jul 1, 2013 at 16:54

15 votes

1 answer

796 views

A finite first order theory whose finite models are exactly the $\Bbb F_p$?

asked Jun 20, 2013 at 8:44

13 votes

4 answers

2k views

Counterexamples in complex analysis

asked Dec 9, 2012 at 11:48

13 votes

2 answers

2k views

Characteristic polynomial of a matrix with zeros on its diagonal

asked Dec 22, 2012 at 19:19

13 votes

3 answers

335 views

An explicit imbedding of $(R\mathbf{-Mod})^{op}$ into $S\mathbf{-Mod}$

asked Jan 6, 2014 at 18:51

12 votes

2 answers

1k views

Does every ring with unity arise as an endomorphism ring?

asked Dec 8, 2012 at 22:44

11 votes

1 answer

555 views

Are there exotic symplectic structures on $ S^2 $?

asked Jul 21, 2013 at 13:10

11 votes

1 answer

598 views

The smallest group with 3 generators

asked Jul 26, 2013 at 19:59

11 votes

3 answers

7k views

Do negative dimensions make sense? [duplicate]

asked Jun 18, 2013 at 19:12

10 votes

1 answer

400 views

Proving a geometric inequality without Lagrange multipliers

asked Jun 12, 2013 at 17:02

10 votes

1 answer

291 views

Is there a universal property for the ultraproduct?

asked Jun 17, 2013 at 18:54

10 votes

2 answers

701 views

Area enclosed by 2-dimensional random curve

asked Dec 5, 2012 at 22:13

10 votes

1 answer

248 views

Universal property characterizing $\Bbb R$

asked Apr 10, 2013 at 21:27

10 votes

1 answer

306 views

Maps of $\mathbb{R}^3$ commuting with the cross product

asked Jan 25, 2013 at 14:28

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91 Questions

Is there a 0-1 law for the theory of groups?

A Topology such that the continuous functions are exactly the polynomials

Is Serge Lang's Algebra still worth reading?

Is every group the automorphism group of a group?

Why should "graph theory be part of the education of every student of mathematics"?

Is $ \pi $ definable in $(\Bbb R,0,1,+,×, <,\exp) $?

If two non-overlapping squares inside a unit square have side lengths $a$ and $b$, prove that $a+b \le 1$.

Is $\Bbb R$ definable in $(\Bbb C,0,1,+,*,\exp)$?

What are the important theorems in the theory of dynamical systems?

Are there interesting rings without unity?

Is the space of smooth sections of a vector bundle finitely generated as a $C^\infty$-module?

How confident can we be about the validity of the classification of finite simple groups?

Most astonishing applications of compactness theorem outside logic

Presentation of Rubik's Cube group

What are some examples of hard theorems in category theory?

Is almost any group generated by two generators?

Etymology of Tor and Ext Functors

A finite first order theory whose finite models are exactly the $\Bbb F_p$?

Counterexamples in complex analysis

Characteristic polynomial of a matrix with zeros on its diagonal

An explicit imbedding of $(R\mathbf{-Mod})^{op}$ into $S\mathbf{-Mod}$

Does every ring with unity arise as an endomorphism ring?

Are there exotic symplectic structures on $ S^2 $?

The smallest group with 3 generators

Do negative dimensions make sense? [duplicate]

Proving a geometric inequality without Lagrange multipliers

Is there a universal property for the ultraproduct?

Area enclosed by 2-dimensional random curve

Universal property characterizing $\Bbb R$

Maps of $\mathbb{R}^3$ commuting with the cross product