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Tomek Kania
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Sep
17
revised
Is an ultrapower of a faithful Banach algebra always faithful?
added 24 characters in body; edited tags; edited title
Sep
12
comment
Hopf Galois extensions and conditional expectations for C* algebras
Let $B\subset A$ be C*-algebras. Then a bounded, linear idempotent $P\colon A\to B$ is a conditional expectation if and only if it has norm 1.
Sep
12
comment
$A$ is isomorphic to $A \oplus \mathbb{Z}^2$, but not to $A \oplus \mathbb{Z}$
Let me ask a weaker question: is there a compact Hausdorff space $X$ such that $X$ is homeomorphic to $X\times \mathbb{T}^2$ but not homeomorphic to $X\times \mathbb{T}$?
Sep
11
answered
Infinite topological direct sum of amenable Banach algebra
Sep
11
awarded
Necromancer
Sep
10
awarded
Nice Answer
Sep
9
comment
Must uncountable compact Hausdorff spaces have large discrete subsets?
Certainly closed discrete subsets of compact Hausdorff spaces are finite. :-)
Sep
9
answered
Must uncountable compact Hausdorff spaces have large discrete subsets?
Sep
1
comment
One question about the tensor product of $L^1(G)$ and a Banach space $A$
Would you please confirm that my answer is fine?
Aug
27
reviewed
Approve
Properties of Coefficients of Order Polynomials
Aug
26
comment
An extension of $K$-theory to topological $^*$-algebras
Might be relevant:
research.lancs.ac.uk/portal/en/publications/…
Aug
23
reviewed
Approve
Can a manifold have a curvature-free connection that is not torsion-free?
Aug
23
reviewed
Approve
Polynomials with roots in convex position
Aug
23
reviewed
Approve
Catalan numbers as sums of squares of numbers in the rows of the Catalan triangle - is there a combinatorial explanation?
Aug
15
awarded
Necromancer
Aug
15
revised
One question about the tensor product of $L^1(G)$ and a Banach space $A$
added 51 characters in body; edited tags; edited title
Aug
15
reviewed
Approve
Example of 4-manifold with $\pi_1=\mathbb Q$
Aug
15
reviewed
Approve
Example of a specific manifold
Aug
15
answered
One question about the tensor product of $L^1(G)$ and a Banach space $A$
Aug
14
revised
Is the space of vectorial functions that are Dunford integrable complete?
added 672 characters in body
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