I am trying to show the following statement
Let $D\subset \mathbb{R}^2$ be an open and bounded subset. $\Pi=(P^x : x \in D )$ a Family of standard Brownian Motions started at $x \in D$. Then $\Pi$ ist a tight (or relativly compact due to Prorhorvs Theorem).
I need that result to proof the existence of a certain type of process on the Sierpinski CarpetProcess. Unfortunately I do not have any experience working with the concept of "tightness". Perhaps Arzelà-Ascoli would work but I have no idea how to apply it.

