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 Oct 13 comment Questions concerning convergence rate of Iterated Projections Added the oc tag as per @StefanKohl's request. Oct 13 revised Questions concerning convergence rate of Iterated Projections edited tags Oct 7 revised A question on unconditionally $p$-summable sequences Improved formatting Oct 1 comment Proposals for polymath projects Sounds interesting. The Wikipedia article for the Worm problem lists known upper and lower bounds for the area as 0.260437 and 0.232239, respectively. Do you hope for tighter bounds, an explicit solution for the area or even the shape? Sep 29 awarded Yearling Sep 25 reviewed Leave Open Mochizuki's “phenomena in number theory” outside the scope of Langlands Sep 24 comment SVD vs Fourier analysis for data. @PaulSiegel I guess the OP has in mind that the discrete Fourier transform transforms discrete "spatial" data to discrete "frequency" data. I would say that the SVD decomposes every matrix $A$ as $U^TDV$ with a diagonal $D$ and orthonormal $U$ and $V$ while the diagonal Fourier transform $F$ is also orthonormal and gives $C = F^HDF$ with diagonal $D$ for circulant matrices $C$. Sep 23 comment In which sense Daubechies wavelets converge to the Shannon wavelet? Well, after your edit, 2 can well be. It would be good to make edits in a way that comments and answers (if there are any) still make sense… Sep 22 comment In which sense Daubechies wavelets converge to the Shannon wavelet? Interesting - do you have a reference for the claim? Well 2. can not hold, since the Fourier transform of the Shannon wavelet is discontinuous while the transforms of the Daubechies wavelet are continuous (if I remember correctly). Sep 22 comment Fréchet differentiability of functional defined by a integral I'm doing my thesis on optimal control so I'm trying to avoid advanced math. Sounds like a not-so-good plan... Sep 21 reviewed Leave Open Spaces $C^\infty(\mathbb T^n\times \mathbb R^n)$, $C^\infty_0(\mathbb T^n\times \mathbb R^n)$ and $\mathscr{S}(\mathbb T^n\times \mathbb R^n)$? Sep 21 reviewed Close Unbounded operator Sep 14 awarded Electorate Sep 3 comment What are your favorite instructional counterexamples? @columbus8myhw The support is the closure of the set where the function is not zero. Sep 1 reviewed Leave Open Non-standard numbers and exponential form of Zeta function Sep 1 reviewed Leave Open Solutions of an nonlinear evolution problem Aug 29 comment Convergence of Fixed-Point Iteration of a dependent map Have you looked at the properties of the corresponding iteration the product space? Aug 24 comment Hyperfunctions supported at a point Ha! Page 5 is not available in google books for me, this explains my ignorance… Aug 24 comment Hyperfunctions supported at a point I don't know much about hyperfunctions but I am not sure what "coincide" should mean here. A distribution is an element in the dual of smooth functions with compact support while a hyperfunction is an equivalence class of holomorphic functionals. I do not see a canonical way to map one set into the other… E.g. how should a hyperfunction act on a smooth function and how to make such an identification that respects all wanted rules (such as the rules for the derivative…)? Aug 22 comment Construct a PDE solution from a net of approximations @AlexM. I guess that your limit is something like "largest set in the partition goes to zero". Why not pick sequences of such converging partitions and show that limits are independent of the subsequences?