Narutaka OZAWA's user avatar
Narutaka OZAWA's user avatar
Narutaka OZAWA's user avatar
Narutaka OZAWA
  • Member for 13 years, 8 months
  • Last seen this week
28 votes

Can nuclearity be determined by tensoring with a single C*-algebra?

21 votes
Accepted

Range of completely positive projection

19 votes
Accepted

Can non-central projections still commute with all other projections?

18 votes
Accepted

Does the hyperfinite II_1 factor admit two irreducible representations that are not unitarily equivalent?

15 votes

Compact subgroups of the unitary group of operators in a hilbert space

14 votes
Accepted

On complemented von Neumann algebras

14 votes
Accepted

Can one detect a cyclic and separating vector for a concrete $C^*$-algebra using a dense subalgebra?

13 votes
Accepted

Examples of groups without the n-positive approximation property

13 votes
Accepted

Criterion for a Banach algebra to be finite dimensional

12 votes
Accepted

Separating vectors for C$^*$-algebras

12 votes
Accepted

positive elements in tensor product

12 votes
Accepted

A variation of the Ryll-Nardzewski fixed point theorem

11 votes
Accepted

Do Baumslag-Solitar Group von Neumann algebras have Property $\Gamma$?

10 votes
Accepted

When does a matrix define a convolution operator on a hypergroup?

10 votes
Accepted

When is the multiplication map of the algebraic tensor product of C*-algebras injective?

9 votes
Accepted

Commutator ideal in nonunital C*-algebra

9 votes
Accepted

Noncommutative torus as a von Neumann algebra

9 votes

Arveson's extension for normal completely positive maps

8 votes

Extension of a bilinear functional

8 votes
Accepted

Masas in second duals of Banach algebras

8 votes
Accepted

Calculation of the norm of linear combinitation of two states on a $C^*$-algebra

8 votes
Accepted

Show that the eigenvalues of a non-symmetric matrix built from positive matrices have positive real parts

8 votes

If $A\hat\otimes B$ has identity then so are $A$ and $B$

7 votes
Accepted

The center of a representation von Neumann algebra, and finite index subgroups

7 votes
Accepted

Trivializing unitary cocycles in abelian von Neumann algebras that are uniformly close to the trivial one

7 votes

Is the set of separable quantum states closed?

7 votes
Accepted

Given a C-star dynamical system and a subgroup of the acting group, is the corresponding map on crossed product algebras necessarily an injection

7 votes
Accepted

When are completely positive maps monic/epic?

7 votes

When $C(X)$ is an injective $C(X)$-module? Current answer is erroneous

7 votes
Accepted

For discrete groups, does the Haagerup property imply the AP of Haagerup-Kraus?