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Markus
  • Member for 7 years, 8 months
  • Last seen more than a week ago
  • Yekaterinburg
8 votes
0 answers
243 views

Complementability of finite dimensional subspaces

8 votes
1 answer
264 views

Subspaces isomorphic with quotients

8 votes
1 answer
392 views

Parallelogram law for vectors of equal length

7 votes
0 answers
229 views

Isometries on the unit sphere

7 votes
2 answers
411 views

Non strictly-singular operators and complemented subspaces

7 votes
1 answer
895 views

Surjective entire functions

5 votes
1 answer
450 views

Compact non-nuclear operators

5 votes
2 answers
382 views

Biorthogonal functionals

5 votes
1 answer
384 views

Quasinilpotent , non-compact operators

5 votes
0 answers
112 views

A characterization of Hilbert spaces by norm one projections

4 votes
1 answer
351 views

Trivial intersection of kernels

4 votes
0 answers
103 views

Hamel basis with all coordinate functionals discontinuous

4 votes
1 answer
287 views

Contact points for John's ellipsoid

3 votes
3 answers
284 views

Do these properties characterize Hilbert spaces?

3 votes
3 answers
265 views

Preannihilators of subspaces of separable duals

3 votes
1 answer
146 views

Operator in the commutant which is small on a given vector

3 votes
2 answers
103 views

Unicellular compact operators

3 votes
2 answers
111 views

Behavior of orbits under small perturbations

3 votes
1 answer
166 views

Rate of convergence of weakly null sequences

2 votes
0 answers
185 views

Reflexive subspaces of dual spaces

1 vote
1 answer
154 views

Extending functionals on $X^*$

1 vote
1 answer
650 views

Annihilators and pre-annihilators