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13h
comment Probability of at most $K$ consecutive zeroes in a sequence of 0s and 1s
Why do you expect this result to be true? and on a related note, where/how does the problem originate?
14h
reviewed Approve 3-dimensional vectors satisfying certain equalities
18h
reviewed Close Probability of an event based on percentage in fixed lapse of time
18h
comment $C^*$-algebra generated by those operators that are bounded on every $\ell_p$
@HannesThiel Thanks for this observation. Having thought about this question a little more, and reading your observation, I now wonder if $B_2$ equals the uniform Roe algebra of the "full permutation group of ${\bf N}$"
1d
comment Weakenings of the Bounded Approximation Property
@BillJohnson I am probably missing something (tiredness and writing homework solutions and wine) but wouldn't any reflexive $X$ satisfy (3) for trivial reasons? In which case we just need a reflexive $X$ without AP, and then one can use the known examples of subspaces of $\ell_p$, $1<p<2$, that don't have AP
1d
reviewed Leave Open Can we do better than zero padding of FFT?
1d
comment weakly p- summable sequence
I'd just like to say that although the question might be better suited to MSE rather than MO, I would personally not vote to close as "unclear what you're asking". The question makes sense to me, although I don't have time to think about it right now
1d
revised weakly p- summable sequence
reformatted to improve clarity
1d
comment Continuous inclusions in Hilbert-Sobolev space $H^s(\mathbb{R}^n) \hookrightarrow \mathcal{E}^k(\mathbb{R}^n)$
I'm voting to close this question as off-topic because it was posted on MSE and ought to get adequate answers there
1d
comment Continuous inclusions in Hilbert-Sobolev space $H^s(\mathbb{R}^n) \hookrightarrow \mathcal{E}^k(\mathbb{R}^n)$
This was also posted to MSE at about the same time that it was posted here math.stackexchange.com/questions/1648094
1d
comment What does spherical harmonics mean?
If you have access to Wikipedia there should be some explanations there. In any case, while your question is a natural one, it is more suited to MathStackExchange than to MathOverflow
1d
comment What is a good book on topological groups?
Does it have anything on Tannaka reconstruction and Pontrjagin duality, as the question mentions?
2d
awarded  Popular Question
2d
comment a naive question: is the category of moniods cartesian closed? Why?
@Oskar How is this a duplicate of a question about commutative monoids, when it is about not-necessarily commutative monoids?
Feb
7
comment AQA A Level Normal Distribution
Dear Dargenor, this is not the appropriate place to get help with A-Level Maths (for more explanation why, please see the information in mathoverflow.net/help )
Feb
7
comment What is a foliation and why should I care?
Speaking as a functional analyst, +1 for the first sentence :)
Feb
7
comment Nonseparable Hilbert spaces
Related to your example 2: there was some recent work of Ando and Haagerup on ultrapowers arxiv.org/abs/1212.5457 which I think made use of spatial representations of these ultrapowers at various points. Just as with the Calkin, faithful representations of these ultrapowers must live on non-separable Hilbert spaces
Feb
6
comment Ideal structure of group $C^*$-agebras
Or if $C_r^*({\bf Z})$ is too easy an example, how about $C_r^*(H_3({\bf Z}))$, where $H_3({\bf Z})$ is the 3-dimensional Heisenberg group over the integers? There was an old article (paywall access I'm afraid) of Anderson and Paschke which looked at this algebra and related objects: math.uh.edu/~hjm/vol15-1.html
Feb
6
comment Ideal structure of group $C^*$-agebras
For instance, since it sounds like you are a newcomer to the world of group Cstar algebras, you should read about the fact that the reduced Cstar algebra of the free group on two generators is simple, as this will give you some flavour of why it is usually hard to deduce properties about the ideal structure of $C_r^*(\Gamma)$ from group-theoretic properties of $\Gamma$.
Feb
6
comment Ideal structure of group $C^*$-agebras
I'm afraid your question is still too broad; please actually provide some examples of the kinds of groups you want. By examples, I mean concrete examples, of particular groups. Every theorem about a general kind of group implies a theorem aout a particular example; in my opinion, as a researcher, if you don't know any examples of those kinds of groups, you need to find them and learn about them