standard mollifier (comparing the definition in Evans and wiki) Hi I am looking at the definition of standard mollifier $\eta$ in Evans, and the $\eta$ from wiki Have a very basic question, is the $\eta$ in Evans also compactly supported? i e $\eta\in C_c^{\infty}$?
functional analysis - The gradient of the standard mollifier . . . Stack Exchange Network Stack Exchange network consists of 183 Q A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers
real analysis - How to prove the mollifier is infinitely . . . I'm learning Evans' PDEs and noticing the "mollifier" in appendix C, which is: $$ \eta(x):= \begin{cases}C \exp \left(\frac{1}{|x|^2-1}\right) \text { if }|x|<1 \\ 0 \text { if }|x| \geq 1\end{cases} $$ I'm having difficulties showing that $\eta \in C_0^{\infty}$ even in 1D case My effort was to establish its arbitrary n-th derivative but
Derivative of mollification - Mathematics Stack Exchange Stack Exchange Network Stack Exchange network consists of 183 Q A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers
Gaussian function as a mollifier? - Mathematics Stack Exchange Stack Exchange Network Stack Exchange network consists of 183 Q A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers