User Ivan Meir

18 votes

1 answer

1k views

Does a function from $\mathbb R^2$ to $\mathbb R$ which sums to 0 on the corners of any unit square have to vanish everywhere?

asked Mar 6 at 13:13

163 votes

46 answers

31k views

Every mathematician has only a few tricks

asked Jun 15, 2020 at 14:39

36 votes

3 answers

6k views

In a topological space if there exists a loop that cannot be contracted to a point does there exist a simple loop that cannot be contracted also?

asked Aug 8, 2019 at 18:50

3 votes

1 answer

170 views

Largest subset of quadratic residues with no pair of elements differing by 1

asked Jul 25, 2022 at 22:54

5 votes

0 answers

77 views

Maximum size of difference sets with a bounded number of prime divisors

asked Jul 20, 2022 at 20:10

17 votes

2 answers

2k views

A proof of Van der Waerden's theorem using a weakened form of Szemeredi's theorem

asked Jan 30, 2022 at 1:06

9 votes

3 answers

1k views

A set with positive upper density whose difference set does not contain an infinite arithmetic progression

asked Feb 20, 2022 at 19:19

2 votes

0 answers

233 views

Solving $x^k+y^k+z^k=w^k$ non-trivially in strictly positive integers

asked Feb 13, 2022 at 11:18

5 votes

1 answer

309 views

Is $\mathbb{Q}$ the orbit of a continuous function that is computable when restricted to $\mathbb{Q}$?

asked Jan 30, 2022 at 22:43

10 votes

3 answers

840 views

Progress in robustifying mathematics - i.e. making mathematical theorems robust to small changes in hypotheses

asked Jan 7, 2022 at 19:40

9 votes

2 answers

626 views

Is $\mathbb{Q}$ the orbit of a rational function under iteration?

asked Jan 4, 2022 at 10:19

33 votes

2 answers

2k views

What is the smallest set of real continuous functions generating all rational numbers by iteration?

asked Jan 1, 2022 at 11:11

2 votes

0 answers

74 views

Is there a finite set of polynomials generating all rational numbers by iteration?

asked Jan 4, 2022 at 9:55

6 votes

0 answers

172 views

Plausible ways to discover higher order fourier analysis

asked Sep 26, 2021 at 10:10

3 votes

0 answers

172 views

Ellenberg and Gijswijt's result on arithmetic progressions in subsets of $\mathbb{F}_q^n$ and a generalisation to sets of linear equations

asked Aug 15, 2020 at 13:08

2 votes

0 answers

182 views

Is the existence of undecidable propositions decidable?

asked Jun 18, 2020 at 19:59

4 votes

0 answers

99 views

Closed curves with minimal total curvature in the unit circle

asked Jun 2, 2020 at 0:46

2 votes

1 answer

150 views

O(1) or o(logn) discrepancy for multiples of an irrational for at least one sub interval

asked Mar 26, 2020 at 14:12

29 votes

2 answers

5k views

Consequences of eigenvector-eigenvalue formula found by studying neutrinos

asked Nov 17, 2019 at 20:23

23 votes

3 answers

4k views

Continuous functions taking uncountably many values countably often

asked Nov 11, 2019 at 20:51

-4 votes

1 answer

196 views

Is there a procedure to derive models from axiomatic systems? [closed]

asked Nov 6, 2019 at 11:35

0 votes

1 answer

701 views

Are all manifolds in $\mathbb R^n$ homeomorphic to a smooth manifold?

asked Aug 30, 2019 at 9:10

7 votes

0 answers

96 views

Rough classification of Peano Curves

asked Aug 29, 2019 at 13:46

4 votes

4 answers

279 views

How many residues mod p do you need to take to ensure that you can always find some multiple that contains 3 elements within ϵ of each other

asked Aug 27, 2019 at 12:06

35 votes

1 answer

2k views

Which polygons can be turned inside out by a smooth deformation?

asked Aug 28, 2019 at 10:01

10 votes

1 answer

883 views

In a subset of $\mathbb{R}^2$ which is not simply connected does there exist a simple loop that does not contract to a point?

asked Aug 10, 2019 at 12:33

3 votes

1 answer

399 views

In which topological spaces does the existence of a loop not contractible to a point imply there is a non-contractible simple loop also?

asked Aug 10, 2019 at 12:07

Stack Exchange Network

27 Questions

Does a function from $\mathbb R^2$ to $\mathbb R$ which sums to 0 on the corners of any unit square have to vanish everywhere?

Every mathematician has only a few tricks

In a topological space if there exists a loop that cannot be contracted to a point does there exist a simple loop that cannot be contracted also?

Largest subset of quadratic residues with no pair of elements differing by 1

Maximum size of difference sets with a bounded number of prime divisors

A proof of Van der Waerden's theorem using a weakened form of Szemeredi's theorem

A set with positive upper density whose difference set does not contain an infinite arithmetic progression

Solving $x^k+y^k+z^k=w^k$ non-trivially in strictly positive integers

Is $\mathbb{Q}$ the orbit of a continuous function that is computable when restricted to $\mathbb{Q}$?

Progress in robustifying mathematics - i.e. making mathematical theorems robust to small changes in hypotheses

Is $\mathbb{Q}$ the orbit of a rational function under iteration?

What is the smallest set of real continuous functions generating all rational numbers by iteration?

Is there a finite set of polynomials generating all rational numbers by iteration?

Plausible ways to discover higher order fourier analysis

Ellenberg and Gijswijt's result on arithmetic progressions in subsets of $\mathbb{F}_q^n$ and a generalisation to sets of linear equations

Is the existence of undecidable propositions decidable?

Closed curves with minimal total curvature in the unit circle

O(1) or o(logn) discrepancy for multiples of an irrational for at least one sub interval

Consequences of eigenvector-eigenvalue formula found by studying neutrinos

Continuous functions taking uncountably many values countably often

Is there a procedure to derive models from axiomatic systems? [closed]

Are all manifolds in $\mathbb R^n$ homeomorphic to a smooth manifold?

Rough classification of Peano Curves

How many residues mod p do you need to take to ensure that you can always find some multiple that contains 3 elements within ϵ of each other

Which polygons can be turned inside out by a smooth deformation?

In a subset of $\mathbb{R}^2$ which is not simply connected does there exist a simple loop that does not contract to a point?

In which topological spaces does the existence of a loop not contractible to a point imply there is a non-contractible simple loop also?