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Yanko
  • Member for 7 years, 4 months
  • Last seen more than a month ago
7 votes
1 answer
1k views

Structure of compact abelian group

7 votes
0 answers
540 views

Cocycles and group extensions

6 votes
1 answer
396 views

Is the family of all continuous functions from a compact metric space to a separable complete metric space separable?

5 votes
1 answer
117 views

An example which disproves $\|p(T)\|_{op} = \|p\|_\sup$ in arbitrary Banach spaces (Gelfand theory).

4 votes
1 answer
420 views

Dense subgroup of torsion elements

3 votes
2 answers
273 views

Short exact sequence, torus and a finite group

3 votes
1 answer
1k views

Homeomorphism and Borel sets

3 votes
3 answers
642 views

Induced Borel $\sigma$-algebra.

3 votes
1 answer
330 views

A commutator with an element of finite order in a nilpotent group

3 votes
1 answer
53 views

Find an isomorphism from $H=\{(s,t)\in S^1\times S^1 : s^m=t^l\}$ to $S^1\times C_n$.

3 votes
1 answer
77 views

Choosing eigenvectors and eigenvalues continuously

2 votes
1 answer
199 views

Extension of a finite group by a connected group necessarily splits?

2 votes
1 answer
92 views

Does $G/\mathbb{T}=H$ implies that $G=\mathbb{T}\oplus H$?

2 votes
0 answers
46 views

Under which conditions a homomorphism $H\rightarrow G\cdot K$ can be splitted into a product of homomorphisms

2 votes
0 answers
95 views

$G\cong G/H\times H$ measurably

2 votes
1 answer
137 views

Why is this group a Lie group?

2 votes
1 answer
454 views

Free module as a vector bundle over the spectrum

1 vote
1 answer
80 views

Is there a name for this?

1 vote
0 answers
528 views

Exactness of the Pontryagin dual (Reference Request)

1 vote
1 answer
251 views

Fubini's theorem for sequences

1 vote
1 answer
86 views

Is there a Borel-measurable projection to a closed subgroup

1 vote
2 answers
156 views

Is there a LCA group $G$ such that $G/\mathbb{T}\cong\mathbb{R}$?

1 vote
1 answer
96 views

Borel set of large measure in product space contains a product set of large measure

1 vote
1 answer
451 views

An anti-symmetric bilinear map $b:V\times V\rightarrow k$ is the difference of two bilinear forms

1 vote
1 answer
57 views

Why is the subset of all vectors whose spectral measure is absolutely continuous with respect to Lebesgue a subspace?

1 vote
1 answer
109 views

Locally compact nilpotent group has an open subgroup isomorphic to $\mathbb{R}^n\times K$

1 vote
1 answer
41 views

Is there such a map $c:\mathbb{N}\times\mathbb{N}\rightarrow \mathbb{R}\backslash\{0\}$?

1 vote
2 answers
45 views

If $\chi(g)$ generates a dense subgroup of $\chi(G)$ for all $\chi$ then $g$ generates a dense subgroup of $G$.

1 vote
1 answer
59 views

A homomorphism which is trivial on the $n$-torsion must have an $n$'th root?

0 votes
1 answer
60 views

$\mathbb{Z}\leq G \leq \mathbb{Q}$ and $\varphi:G\rightarrow H$ a map which behaves nicely on fractions.