Nik Weaver's user avatar
Nik Weaver's user avatar
Nik Weaver's user avatar
Nik Weaver
  • Member for 11 years, 11 months
  • Last seen this week
51 votes
2 answers
3k views

vector balancing problem

47 votes
0 answers
2k views

Set-theoretic reformulation of the invariant subspace problem

37 votes
1 answer
2k views

What is the meaning of this analogy between lattices and topological spaces?

34 votes
8 answers
4k views

Uncountable counterexamples in algebra

33 votes
1 answer
3k views

Fourier transform on the discrete cube

24 votes
2 answers
2k views

Unique predual of a Banach space

23 votes
9 answers
2k views

Nonseparable counterexamples in analysis

22 votes
1 answer
2k views

Who proved that $l^1$ and $L^1[0,1]$ are not isomorphic?

21 votes
6 answers
2k views

What are the possible eigenvalues of these matrices?

21 votes
3 answers
1k views

Separating pure states on the $2\times 2$ matrix algebra

20 votes
3 answers
1k views

Simultaneous "orthonormalization" in $\mathbb{C}^4$

16 votes
6 answers
2k views

Finding closed subspaces whose sum isn't closed

15 votes
1 answer
1k views

Existence of double eigenvalue

15 votes
0 answers
605 views

Countably decomposable von Neumann algebras

15 votes
0 answers
341 views

Is there support for the term "Gelfand algebra"?

15 votes
2 answers
1k views

Open coloring axiom vs. CH

14 votes
1 answer
762 views

Ordinary mathematics in Chang's model

13 votes
2 answers
355 views

Connected incomparability graph

12 votes
2 answers
1k views

Another $2 \times 2$ matrix question

12 votes
2 answers
745 views

Term for a metric space for which the triangle inequality is strict?

11 votes
1 answer
411 views

Shift invariant subspaces of $l^1$

11 votes
2 answers
745 views

Are topological PID's Noetherian?

10 votes
1 answer
617 views

$2 \times 2$ matrix question

10 votes
0 answers
249 views

What are these matrices called?

10 votes
2 answers
259 views

Weak* continuity of positive parts

10 votes
1 answer
710 views

Real-valued measurable cardinals

8 votes
1 answer
224 views

Non-isomorphic graphs with isomorphic edge vectors

8 votes
2 answers
357 views

$l^1$ versus $l^2$

8 votes
1 answer
746 views

approximate uncertainty principle for finite abelian groups

7 votes
1 answer
396 views

Geometry of Hermitian rank $\leq r$ matrices