User Ivan Feshchenko - MathOverflow

Ivan Feshchenko

Member for 9 years, 6 months
Last seen more than 1 year ago

Kyiv, Ukraine

12 Questions

Score Activity Newest Views

28 votes

2 answers

3k views

Can a countable union of two-element sets be uncountable?

asked Feb 8, 2022 at 20:19

19 votes

2 answers

2k views

Can we take a supremum over all Hilbert spaces?

asked Nov 5, 2020 at 21:31

8 votes

2 answers

862 views

Continuous linear functionals and the Axiom of Choice

asked Oct 14, 2021 at 20:54

5 votes

0 answers

252 views

Completeness of the space $L^p$ and the Axiom of Countable Choice

asked Feb 3, 2022 at 20:41

5 votes

1 answer

359 views

Inverse marginal property of a collection of $\sigma$-algebras

asked Apr 22, 2020 at 17:59

5 votes

2 answers

2k views

Extension of bounded linear operators

asked Mar 12, 2014 at 19:28

3 votes

0 answers

369 views

Dissection of a polygon into convex polygons

asked Oct 3, 2014 at 13:38

2 votes

0 answers

341 views

When is the sum of complemented subspaces complemented?

asked May 2, 2016 at 11:16

2 votes

0 answers

161 views

Algebraic connectivity of the path $P_n$

asked Jul 19, 2019 at 17:11

2 votes

1 answer

444 views

Can we choose an element from a class?

asked Mar 24, 2021 at 19:10

0 votes

1 answer

462 views

Is a function needed here?

asked Apr 7, 2021 at 21:41

0 votes

1 answer

296 views

Can we choose a sequence of Hilbert spaces?

asked Apr 19, 2021 at 17:58