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seen Apr 22 at 11:31

Apr
22
comment Characterizations of Wiener algebra
Thanks for your answer. Question (1) was only intended to clarify the priorities in a reference list.
Apr
21
asked Characterizations of Wiener algebra
Mar
19
asked Lipschitz-free spaces of $\mathbb R^n$
Mar
13
comment Predual of a subspace
Great, thank you very much.
Mar
12
comment Predual of a subspace
Yes, I mean weak-star closed.
Mar
12
revised Predual of a subspace
deleted 15 characters in body; edited title
Mar
12
asked Predual of a subspace
Mar
11
answered Structure of sign changes under the heat flow
Mar
5
asked Global existence for infinite dimensional ODE
Mar
5
awarded  Yearling
Mar
5
answered Boundedness of a singular integral operator on $L^p(\mathbb{R})$, $1<p<\infty$
Mar
3
comment Infinite dimensional Cauchy-Lipschitz theorem
Thanks for your answer, you are right.
Mar
3
comment Infinite dimensional Cauchy-Lipschitz theorem
For a counterexample to Peano's theorem in infinite dimension, check for instance Exercise 18, page IV.41 of the Bourbaki’s volume Fonctions d'une variable réelle.
Mar
2
asked Infinite dimensional Cauchy-Lipschitz theorem
Feb
11
comment Non-separable Banach space
Illuminating! Thanks.
Feb
10
asked Non-separable Banach space
Feb
7
comment Extremal eigenvalues & eigenvectors of skew-adjacency matrix
How about calculating $\sqrt{B^*B}=\vert B\vert$?
Feb
6
answered Extremal eigenvalues & eigenvectors of skew-adjacency matrix
Feb
2
comment Surjectivity of curl
@Denis Serre: I do not understand your Borel-type argument for the smoothness of $w^0$ at the origin. The size of $w_k$ on the sphere could be anything and your argument ("differs from…") would provide smoothness for $\sum_{k\ge 0}\phi(kx)a_k x^k$ for any sequence. Given a sequence $(a_k)_{k\ge 0}$, it is possible to choose a sequence $(\mu_k)_{k\ge 0}$ (depending heavily on the $a_k$) such that $\sum_{k\ge 0}\phi(\mu_k x)a_k x^k$ is smooth (i.e. $C^\infty$).
Feb
1
comment Series estimate
Nice shot, thanks.