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Markus's user avatar
Markus's user avatar
Markus
  • Member for 9 years
  • Last seen this week
  • Yekaterinburg
14 votes
1 answer
658 views

Sums of non-surjective entire functions

8 votes
0 answers
303 views

Complementability of finite dimensional subspaces

8 votes
1 answer
289 views

Subspaces isomorphic with quotients

8 votes
1 answer
431 views

Parallelogram law for vectors of equal length

7 votes
0 answers
241 views

Isometries on the unit sphere

7 votes
2 answers
428 views

Non strictly-singular operators and complemented subspaces

7 votes
1 answer
1k views

Surjective entire functions

7 votes
1 answer
220 views

A characterization of Hilbert spaces by norm one projections

5 votes
1 answer
174 views

On a property for normed spaces

5 votes
1 answer
449 views

Quasinilpotent , non-compact operators

5 votes
1 answer
487 views

Compact non-nuclear operators

5 votes
2 answers
477 views

Biorthogonal functionals

5 votes
1 answer
350 views

Contact points for John's ellipsoid

4 votes
0 answers
125 views

Hamel basis with all coordinate functionals discontinuous

4 votes
1 answer
380 views

Trivial intersection of kernels

3 votes
2 answers
113 views

Behavior of orbits under small perturbations

3 votes
1 answer
173 views

Rate of convergence of weakly null sequences

3 votes
1 answer
154 views

Operator in the commutant which is small on a given vector

3 votes
2 answers
127 views

Unicellular compact operators

3 votes
3 answers
313 views

Do these properties characterize Hilbert spaces?

3 votes
3 answers
341 views

Preannihilators of subspaces of separable duals

2 votes
0 answers
193 views

Reflexive subspaces of dual spaces

1 vote
1 answer
158 views

Extending functionals on $X^*$

1 vote
1 answer
861 views

Annihilators and pre-annihilators

1 vote
1 answer
223 views

Isometries of Hilbert space

1 vote
0 answers
120 views

Non-surjective isometries of $l_p$