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Stefan Geschke's user avatar
Stefan Geschke's user avatar
Stefan Geschke's user avatar
Stefan Geschke
  • Member for 12 years, 8 months
  • Last seen more than a month ago
82 votes
Accepted

What is the cardinality of the set of all topologies on $\mathbb{R}$?

33 votes
Accepted

True vs. Provable

26 votes
Accepted

Why Euclidean geometry cannot be proved incomplete by Gödel's incompleteness theorems?

20 votes
Accepted

How do you pronounce the inverse of the $\in$ relation? How do you say $G\ni x$?

19 votes
Accepted

Proof that convex open sets in $\mathbb{R}^n$ are homeomorphic?

13 votes

Is $\mathbb{R}$ the only ordered field?

13 votes
Accepted

A non-arithmetical set?

12 votes

How to show a matrix is full rank?

11 votes

first countable $\Leftrightarrow$ compact and Hausdorff?

11 votes
Accepted

uniqueness of a direct limit

9 votes

What does "refinement" mean?

8 votes
Accepted

How it is possible that sound system is inconsistent

8 votes
Accepted

Learning approach of simultaneously enhance creation and imagination skills instead of 'follow' approach

8 votes

Motivation for Topology study in Real Analysis

8 votes

On the Volume of Compact matrix Lie groups

8 votes

Are there situations outside of set theory where it would be useful if $\mathrm{ICF}$ were true?

7 votes
Accepted

Intersection of compact and discrete subsets

7 votes
Accepted

Ideals in the ring of endomorphisms of a vector space of uncountably infinite dimension.

7 votes
Accepted

Set Theory- Generalized form of distributivity of unions over intersections

7 votes

How can you construct a topology from a fundamental system of neighborhoods?

6 votes
Accepted

Axiom schema and the definition of natural numbers

6 votes
Accepted

How many countable models of ZFC are there?

6 votes
Accepted

Why are Hornsat, 3sat and 2sat not equivalent?

6 votes
Accepted

measure theory - cantor set

6 votes
Accepted

What is the isomorphism between $\wedge^n(V)$ and $\mathbb{R}$?

6 votes
Accepted

Proof to motivate the need for measure theoretic probability

5 votes

Difference between graph homomorphism and graph isomorphism

5 votes
Accepted

When is there in a probability space no null sets?

5 votes

Aftermath of the incompletness theorem proof

5 votes

Fraïssé limits and groups