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Results tagged with fa.functional-analysis
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user 129831
Banach spaces, function spaces, real functions, integral transforms, theory of distributions, measure theory.
6
votes
Accepted
Can I find a bump function $\psi$ such that $\nabla\log\psi$ vanishes too?
Elaborating the comment by Wojowu: If we take a look at $n=1$ and $\psi\in C^\infty_{\text c}(\mathbb R)$ is a function satisfying conditions 1., 2. and 3. of your question, then for every $x\in]-1,1[ …
- 1,326
3
votes
0
answers
450
views
Opposite of the curl operator and Biot-Savart kernel
Note: I just realized that using $\omega$ and $w$ might not have been the smartest choice of notation -- Sorry about that.
Let $\renewcommand{\div}{\operatorname{\div}}Q_0, Q_1$ be two real numbers, $ …
- 1,326