Franka Waaldijk's user avatar
Franka Waaldijk's user avatar
Franka Waaldijk's user avatar
Franka Waaldijk
  • Member for 7 years, 4 months
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12 votes

Is Lagrange's Theorem equivalent to AC?

12 votes
Accepted

Contrasting theorems in classical logic and constructivism

10 votes
Accepted

BISH: If a function is pointwise positive, is its infimum positive?

10 votes
Accepted

Constructivist defininition of linear subspaces of $\mathbb{Q}^n$?

10 votes

Does the Brouwer fixed point theorem admit a constructive proof?

7 votes

Mathematics without the principle of unique choice

6 votes

Mathematical theory of aesthetics

6 votes
Accepted

Choice sets and the axiom of choice

6 votes

Constructive proof of a rational version of Perron-Frobenius?

6 votes

Is there any physical or computational justification for non-constructive axioms such as AC or excluded middle?

6 votes
Accepted

How much of the Cantor-Schröder-Bernstein theorem is constructively recoverable if the injections have retractions and decidable images?

5 votes
Accepted

Partitions of unity in constructive mathematics

4 votes
Accepted

Why is the notion of algorithm a primitive one in Brouwer's intuitionism?

4 votes

Uncountability of the real numbers from LLPO without countable choice

3 votes

In choiceless constructivism: If $f'=0$ then is $f$ constant?

3 votes

Matrix diagonalization and eigenvector computation constructively

3 votes

Approximate intermediate value theorem in pure constructive mathematics

3 votes

Question: How to find the smallest value $x$ satisfying the equation: $x^2 = a \pmod c$ (known is $a$ and $c$, $c$ is not the prime)?

2 votes

Adding nonconstructive disjunction to intuitionistic logic

2 votes

Strict and non-strict orderings

2 votes

On provability of false statements in constructive mathematics

1 vote

Topology: what defines (non-trivial) paths as being the same trace (curve)?

1 vote
Accepted

Fixed-point property and $T_0$ separation property

1 vote

Minimal covering sets in families of sets intersecting in at most $1$ point

1 vote

Constructive proof of existence of non-separable normed space

1 vote

Maximin diameter of a transformed convex figure

1 vote

Admissibility of Harrop's rule, computationally

1 vote

Are all functions in Bishop's constructive mathematics continuous?

0 votes

How strong is Cantor-Bernstein-Schröder?