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Iosif Pinelis
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$\newcommand\si\sigma$Yes.

Consider first the case $p\ge1$. Then $$F_p:=F_p(m,\si)=\|(\si-1)Z+mR||_p\le|\si-1|\,\|Z\|_p+|m| \le\|Z\|_p\sqrt2\, F_2,$$ where $Z$ and $R$ are independent random variables, $Z$ is standard normal, $R$ is Rademacher (with $P(R=\pm1)=1/2$), and $\|X\|_p:=(E|X|^p)^{1/p}$.

On the other hand, again for $p\ge1$, by Jensen's inequality, conditioning on $R$ and then on $Z$, we get $$F_p\ge\max(|\si-1|\,\|Z\|_p,|m|)\ge\frac{F_2}{\sqrt2}.$$

Now consider the case $p\in(0,1)$. Then, by Jensen's inequality, $$F_p\le F_2.$$ Finally, again for $p\in(0,1)$, by the central limit theorem and the Haagerup inequality, $$F_p\ge2^{1/2-1/p}F_2.$$

Iosif Pinelis
  • 128k
  • 8
  • 107
  • 229