3 problems

Let $P(\Delta)$ be an operator on a product of p.c.f. fractals, and let $P_0$ be the principal part of $P$. The operator is quasielliptic if there is a constant $c>0$ such that … f…

Let $P$ be a polynomial in $m$ variables and let $P(\Delta)$ be the corresponding operator on a product of p.c.f. fractals. For a multi-index $\kappa$, write $D^{\kappa}P$ for the…

Let $X$ be a p.c.f. fractal, let $P$ be a polynomial, and let $P(Delta)$ denote the associated operator on the product space $X^m$. The operator $P(Delta)$ is elliptic when…