I read that for $j\in L^1({\mathbb R}^n)$ with $\|j\|_1=1$ and $f\in L^1_{\rm loc}({\mathbb R}^n)$ the mollifiers $j_\epsilon(x):=\epsilon^{-n}j(x/\epsilon)$ exhibit $j_\epsilon\ast f\in L^1({\mathbb R}^n)$ and $j_\epsilon\ast f\rightarrow f$ in $L^1({\mathbb R}^n)$ as $\epsilon\rightarrow 0$. But convergence in $L^1({\mathbb R}^n)$ does not imply convergence almost everywhere, yet I couldn't find a counterexample for this case, so do we additionally have $j_\epsilon\ast f\rightarrow f$ pointwise almost everywhere or not?
2026-04-02 15:35:08.1775144108
Almost everywhere convergence of convolution with mollifiers
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